Hemicytherura Elofson, 1941 contains over 100 species globally, described mostly from fossil and subfossil assemblages. They are minute, mostly phytal ostracods, with an intricate pattern of fossae and muri on the surface of the shell. This pattern has been used to define four species groups in the genus, but only 10 living species from Japan and Taiwan have been classified using this labelling. Eight species have been reported so far from Korea, albeit mostly briefly. Here we study six species, collected from eight littoral localities on the South Korean mainland and Jeju Island: Hemicytherura cuneata Hanai, 1957; Hemicytherura japonica Kaseda & ikeya, 2011; Hemicytherura kajiyamai Hanai, 1957; Hemicytherura occidens n. sp., Hemicytherura okuboi Kaseda & ikeya, 2011; and H. sp. The new species is proposed based on morphological and genetic differences in partial ITS and CO1 regions; these two genes were also used to test the phylogenetic basis of the existing species groups. Morphologically, H. occidens is very similar to Hemicytherura huangi Kaseda & ikeya, 2011, Hemicytherura notoensis Kaseda & ikeya, 2011, and H. okuboi, but differs from all three in the appearance of the outer clasping apparatus on the hemipenis. Phylogenetic tree resulting from the analysis of the ITS region (but not CO1) supports a close relationship of the new species with H. kajiyamai and H. okuboi (both members of the kajiyamai-group) with high posterior probabilities. The other three Korean species studied belong to the cuneata-group. The existing four groups are used to classify another 25 Hemicytherura species, and two new groups (anomala and clathrata) are proposed for further 18 species. Our new groups are also based on the surface ornamentation of the shell, but without using fossae and muri labelling.

Genus Hemicytherura (Crustacea, Ostracoda) in Korea with description of a new species and the first insight into its molecular phylogeny

This preliminary study investigates the trace-element composition of ostracod shells (Ostracoda: Crustacea) as biogenic calcium carbonates in their role as environmental sentinels of pollution. Using high-resolution in-situ analysis, we compared two contrasting coastal systems: the highly urbanized seascape of metropolitan megacity Hong Kong (HKSAR) and the agriculturally dominated waters of rural retreat Jeju Island, Republic of Korea (ROK). The goal was to assess whether anthropogenic stress gradients affect trace element-to-calcium ratios (E/ Ca) in the carapaces of shallow-marine Neonesidea Maddocks, 1969 species. Hereby, the focus is laid on potential differences in the effects of extreme urbanization and extreme agriculturalization. We analyzed 12 trace elements commonly incorporated into ostracod shells using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Only Mn/Ca, Mg/Ca, and Ni/Ca ratios showed strong correlations with specific seawater physicochemical parameters. Notably, Mn/Ca differed significantly between the two sites, seemingly driven mainly by variations in nitrite nitrogen levels. This suggests that Mn incorporation is sensitive to pollution source, urban versus agricultural, though species-specific uptake effects cannot be excluded. No significant differences in elemental uptake were found between adult and A-1 juvenile stages of Neonesidea mutsuensis Ishizaki, 1961 or Neonesidea elegans (Brady, 1969), supporting the use of both age groups in environmental reconstructions and increasing potential sample yields. While remaining empirical and exploratory, our tentative findings suggest that ostracod geochemistry holds promise for marine pollution monitoring and cautiously supports the application of ostracod Mn/Ca ratios to reconstruct anthropogenic, particularly nitrogen-related, impacts in nearshore environments using sediment core records.

Ostracod shell chemistry as proxy for coastal marine conditions of a highly urbanized megacity (Hong Kong SAR) and an agro-centric oceanic province (Jeju Island, Republic of Korea) - a preliminary comparative analysis

Despite widespread oxycodone misuse, the role of serotonin in opioid addiction remains understudied compared to dopamine. This study investigated the acute effects of oxycodone (2.5 mg/kg, i.v.) on serotonergic neurotransmission in the rat nucleus accumbens core using high-resolution electrochemical methods. We employed fast-scan cyclic voltammetry (FSCV) to monitor medial forebrain bundle stimulation-evoked phasic release and N-shaped multiple cyclic square wave voltammetry (N-MCSWV) to measure tonic concentrations in urethane-anesthetized rats. Results demonstrated a distinct dissociation between tonic and phasic dynamics. Tonic serotonin levels increased significantly (+23.4 nM) from baseline 1-h post-administration. Conversely, stimulation-evoked phasic release initially increased (+24%) but subsequently declined below baseline. Kinetic analysis revealed that serotonin production and maximum reuptake rates followed a similar pattern of initial increase followed by a decrease. In conclusion, oxycodone acutely modulates serotonergic signaling in the nucleus accumbens core by differentially affecting phasic and tonic neurotransmission. These findings demonstrate oxycodone induces temporal dynamics in phasic versus tonic serotonergic signaling in the nucleus accumbens core, highlighting the value of multimodal electrochemical approaches for dissecting opioid neurochemical effects.

Effects of oxycodone on tonic levels and phasic release of serotonin in the rat nucleus accumbens core

A new ostracod species, Heterocypris exodonta Bonilla-Flores & Karanovic, sp. nov. is described from a high-altitude temporary pond near Nam Co, Southern Tibetan Plateau. Detailed morphological analyses of valves, soft body, and the partial mitochondrial COI (cytochrome c oxidase subunit I) sequence distinguish this species from its close congeners, Heterocypris incongruens and Heterocypris salina. Key taxonomic features include the morphology of the female genital lobe and the structure of the internal opening of normal pores, particularly variations in the female genital aperture at the intersection of the seminal duct and the oviduct. Pore openings in H. exodonta Bonilla-Flores & Karanovic, sp. nov. and H. incongruens exhibit a turbine shape, while in H. salina they display a simple aperture. Phylogenetic analysis based on the COI dataset supports the new species description and suggests potential synonymy and cryptic species within the H. salina and H. incongruens complexes. Ecologically, these species mainly inhabit temporary water bodies with high oxygen levels and likely follow an r-type ecological strategy, being opportunistic in colonizing new habitats, reproducing via parthenogenesis, and undergoing rapid population growth. This study enhances the understanding of Southern Tibetan Plateau ostracod biodiversity, providing crucial morphological and molecular data for species identification, particularly for parthenogenetic species lacking standard male morphological characters. Additionally, this research offers methods to prevent misidentifications and misinterpretations in (paleo-)ecological studies, contributing significantly to the broader knowledge of taxonomy and ecology of ostracods from the Southern Tibetan Plateau. Due to the high morphological plasticity of Heterocypris incongruens, our findings highlight the need for caution when identifying similar species, as external resemblance may conceal genetic divergence.

Heterocypris exodonta sp. nov. (Ostracoda, Cyprididae), morphological and molecular description of a high altitude asexual microcrustacean from the Nam Co region, Southern Tibetan Plateau

For many ostracod groups in Korea, published records are missing or are very limited. Loxocaudinae is one such subfamily, with only one named species, Loxocauda orientalis Schornikov, 2011 reported from Korea. Having fewer than 50 species, this subfamily can be considered a small ostracod group, with most of the species known only by their shell morphology. The diagnoses of genera are based on the shell characters that are often homoplastic, and soft body appendages that are difficult to observe, such as the mandibular exopodite. Because of this, the validity of the entire subfamily and some of its genera have been questioned. Here three Loxocaudinae species were collected from the marine macrobenthic assemblages from Korea. Two are new and belong to the genus Glacioloxoconcha Hartmann, 1990, previously known only from Antarctica: Glacioloxoconcha jeongokensis sp. nov. and Glacioloxoconcha jisepoensis sp. nov. Loxocauda orientalis is briefly redescribed, with some of the populations having unusual morphological features. COI and 18S rRNA sequences of all three species are provided and the latter marker used to assess the position of the subfamily within the family Loxoconchidae and the superfamily Cytheroidea. The resulting tree shows that within the family Loxoconchidae, the genera Glacioloxoconcha and Loxocauda Schornikov, 1969 are the most closely related, with very shallow but well-supported branches. Polyphyletic and paraphyletic natures of several Cytheroidea families are discussed, inferred from the reconstructed phylogeny.

Three Loxocaudinae species (Ostracoda, Podocopida) from South Korea

Parasterope Kornicker, 1975 is a marine ostracod genus with 49 species described so far, which makes it the most diverse representative of the subfamily Cylindroleberidinae, as well as the entire family Cylindrole-berididae. Despite its global distribution no species are reported from South Korea. Three new species collected from the Korean coast of the Sea of Japan (Parasterope busanensis sp. nov., P. singula sp. nov., and P. sohi sp. nov.), and one from the Japanese coast of the Pacific Ocean (P. sagami sp. nov.) are described. A taxonomic key to all named species from East Asia is provided. A phylogenetic tree is reconstructed based on partial 16S rRNA sequences of the four new species and other Cylindroleberidinae available from GenBank. Monophyly of Parasterope is supported by high posterior probabilities, but the phylogenetic analyses also indicate that some of the GenBank data attributed to this genus are probably misidentifica-tions. A map of distribution and a checklist of all described Parasterope species are also provided.

Four new Parasterope (Ostracoda, Myodocopina) from the Northwest Pacific and their phylogeny based on 16S rRNA

The biological traits of invertebrates inhabiting freshwater methane seeps are poorly understood. We analysed the relationship between invertebrate abundance and environmental factors such as methane concentration, location of gas hydrates in sediments, sediment composition, and the total number of microorganisms (TNMs), including methanotrophs. The abundance of invertebrates varied greatly (CV 10–136%) across box core samples and stations. No significant differences (P > 0.05) in the abundance of invertebrates were found between stations with sluggish methane discharge, methane concentrations, and gas hydrates located deep in sediments (> 70 cm) and the reference stations. The abundance of meio- and macrobenthic invertebrates reached ~ 130,000 ind. m−2 around gas hydrates ~ 30 cm deep in the sediments. The abundance of nematodes significantly depended on the presence of sulfur bacteria and copepod detritus, while oligochaetes were correlated with the TNMs. Amphipod abundance was dependent on the number of methanotrophic bacteria, while ostracods and copepods showed no dependence on the studied biotic factors. Stable isotope analysis of δ13C and δ15N indicated that oligochaetes and chironomids consumed different proportions of chemosynthetic carbon. Most benthic invertebrates also formed aggregates, possibly enabling the complete utilization of food resources.

Sluggish methane discharge and biological traits of benthic invertebrates in Lake Baikal

Sclerochilus Sars, 1866 is the most diverse genus of the family Bythocytheridae, one of the longest surviving groups of extant ostracods, and the oldest representative of the superfamily Cytheroidea. It has a worldwide distribution at various marine depths, and it includes three subgenera: Fascichilus Schornikov, 1981; Praesclerochilus Schornikov, 1981; and Sclerochilus Sars, 1866. We describe Sclerochilus (Praesclerochilus) jejuensis sp. nov. from Jeju Island, South Korea, raising the number of known Praesclerochilus species to 13. Although most species belonging to this subgenus have very similar carapace shape, the new species differs morphologically from its most similar congeners, S. (P.) mukaishimensis Okubo, 1977; S. (P.) pruniformis Schornikov, 1981; and S. (P.) ochotensis Schornikov, 1981, by the large ventral process on the hemipenis. So far, 29 Sclerochilus species have been reported from South Korea, only one of which was named, but for which no descriptive information was provided. Therefore, this is the first taxonomic report of a Sclerochilus species from South Korea.

One new Sclerochilus (Praesclerochilus) Sars (Ostracoda) species from Korea

Copepods are well studied in South Korea, with the exception of marine non-parasitic cyclopoids, and es-pecially cyclopinids; only three species were found so far here, and only one of them is endemic. A survey of intertidal interstitial faunas from sandy beaches revealed four endemic members of the genus Cyclopina Claus, 1863, which represents the first record of the largest cyclopinid genus in South Korea. A detailed study of their morphology revealed numerous differences, including in rarely studied cuticular organs. Some of these micro-characters could easily be homologised and showed little intraspecific variability, which might prove invaluable for matching sexes and reconstructing phylogenetic relationships. Cyclopina busanensis sp. nov. is described from both sexes collected near Busan (South Coast of South Korea), and is most similar to the only congener from Japan: C. kiraensis Horomi, 1984. Cyclopina koreana sp. nov. is described from both sexes collected near Gangneung (East Coast), and has no close relatives among currently known species. Cyclopina curtijeju sp. nov. is described from two females from Jeju (off South Coast); it is possibly closely related to C. smirnovi Herbst, 1982, but the latter is known from a single male from the Russian Far East. Cyclopina wido sp. nov. is described from both sexes from Wido (West Coast), and shows numerous reductions in segmentation and armature of appendages, most of them probably a consequence of its diminutive size. A table of 26 discrete and continuous characters commonly used in the taxonomy of this group is provided for 48 valid species and subspecies of Cyclopina.

Four new Cyclopina (Copepoda, Cyclopinidae) from South Korea

Five new species of the genus Sarsamphiascus Huys, 2009 were collected from a small Korean beach, which is a record for the number of syntopic copepod congeners. They differ in numerous macro-morphological characters, some of which extend generic boundaries, and are classified in two species groups. Diossacins are widely regarded as taxonomically problematic, and the new discovery presents an opportunity to test characters commonly used in their systematics through a cladistic analysis. Another aim is to test with landmark-based geometric morphometrics the extent of inter- and intraspecific variability of characters with reported significant variation but commonly used in diosaccin taxonomy. The cladistic analysis, based on 14 binary characters, reveals at least three distinct clades among five new species, which, in addition to significant size differences, probably facilitates their syntopy. Some characters previously used to distinguish species groups in Sarsamphiascus, and to distinguish this genus from other diosaccins, are exposed as symplesiomorphies, suggesting that some of these groups might not be monophyletic. Studies of alternative characters are suggested, including cuticular organs on somites, which are surveyed for the first time in this genus. Principal component analysis (PCA) of nine landmarks on the female fifth leg exopod reveals that 70% of variability can be explained by the first two eigenvectors and that in morphospace there is no overlap between Korean species, despite a significant intraspecific variability. Discriminant function analysis with cross-validation shows highly significant results, both in parametric tests and after 10,000 permutation runs, correctly classifying all specimens for all species pairs and suggesting the fifth leg exopod as an ideal taxonomic character here. Evolutionary integration of the morphometric data is tested by plotting PCA scores onto the cladistic tree; randomized permutation test suggests an absence of statistically significant phylogenetic signal.

Cladistic and quantitative shape analyses of five new syntopic Sarsamphiascus (Copepoda, Harpacticoida): problems and solutions for diosaccin systematics and taxonomy

Two new planktonic ostracods of the genus Proceroecia Kock, 1992, P. hwanghaensis sp. nov. and P. joseondonghaensis sp. nov., collected from neritic waters off the south coast of South Korea are described. Morphologically, they are similar to P. microprocera (Angel, 1971), the type species of the genus, but show several clear morphological differences, most prominent being the shape of the male endopodite on the second antenna and the presence of a sensilla on the coxale of the fifth limb. The two new species have subtle differences, such as the length of the frontal organ, number of spines on the comb-like e-seta on the first antenna in males, number of spinules on the b-seta on the second antenna in females, etc. Sequences derived from partial mitochondrial cytochrome oxidase c subunit 1 (mtCOI) for these novel species have been compared with sequences available for other Proceroecia species on GenBank, including P. microprocera. These comparisons suggest that both new species are distinct taxa. They also indicate that one set of sequences on GeneBank previously attributed to P. microprocera and derived from material collected from Chinese waters, belong to P. hwanghaensis, and that another set of sequences of an unidentified Proceroecia species from the South China Sea can be attributable to P. joseondonghaensis. Hence, these new species occur widely in the neritic waters of East Asia. The present study increases the number of the known Proceroecia species to nine, and the numbers of halocyprid ostracod species recorded from Korean waters to six.

Description of two new Proceroecia species (Ostracoda: Halocyprididae) from neritic waters off South Korea with an insight into the morphological and molecular diversity of the genus

Ostracods are small-sized crustaceans, which inhabit all aquatic ecosystems and, because they have a comprehensive fossil record, are important environmental and paleoenvironmental indicators. However several aspects of the ecology of modem species (the basis for the paleontological investigations) are still controversial. Previous authors have raised the hypothesis that benthic ostracods, because of their calcified carapaces, are unable to survive below the Carbonate Compensation Depth (CCD). Herein we test this hypothesis based on (1) ostracods newly collected from the Kuril-Kamchatka Trench at depths far below the CCD during the KuramBio II expedition; and (2) a compilation of all previously published records of (geologically) Recent deep-sea Ostracoda in regions deeper than 3500 m. The KuramBio II expedition provided hundreds of living, hadal ostracods from at least 30 species and 21 genera from thousands of meters deeper than the CCD in the Kuril-Kamchatka Trench region. Additionally, the KuramBio II expedition provided the deepest record (9307 m) of a living ostracod with calcified carapaces: specimens of the genus Krithe. Finally, the compilation of all published information on living ostracods show that a highly diverse assemblage both at high and low taxonomic levels (2 subclasses, 4 suborders, 25 families, 89 genera and at least 206 species) occur below 3500 m. Therefore, we conclude that contrary to previous beliefs, the new data from the Kuril-Kamchatka Trench and the compilation of the literature show that ostracods do live and are even sometimes abundant below the CCD.

Review of Ostracoda (Crustacea) living below the Carbonate Compensation Depth and the deepest record of a calcified ostracod

Identification of animals is often hindered by decoupling of phenotypic and molecular evolutionary rates. The Acanthocyclops vernalis (Fischer, 1853) complex is arguably the most problematic group of cyclopoids and possibly of all copepods, with diversity estimates based on morphology ranging from 2 to 34 taxa. We reconstructed their phylogeny based on one nuclear and three mitochondrial markers, revealing only four species in the Holarctic and always the following sister-species pairs: vernalis-europensis sp. nov. and robustus-americanus. Landmarks for quantitative shape analyses were collected from 147 specimens on five structures commonly used to delineate cyclopoids. Procrustes ANOVA showed small directional asymmetry in all datasets, but large sexual dimorphism in shape and size. Allometry was also highly significant. Principal component analyses of size-corrected data almost completely separated species in morphospace based on the last exopodal and endopodal segments of the fourth leg. These two structures showed the highest amount of covariation, while modularity could not be proven and a phylogenetic signal was only observed in one structure. Spinules and sensilla have a limited use in delineating species here. Calculating mean shapes and the extent of inter and intraspecific phenotypic variability opens new horizons for modern taxonomy.

Taming extreme morphological variability through coupling of molecular phylogeny and quantitative phenotype analysis as a new avenue for taxonomy

We combine geometric morphometric and molecular data to study shell shape changes in eurybathic ostracod Polycope pseudoinornata Chavtur, 1983 and discuss its occurrence in relation to environmental variables (of the sediment and deep water masses). Pairwise distances between 50 mitochondrial COI sequences indicate that populations from five sampled depths and nine localities in the Nordic Seas belong to one species, and haplotype network shows that populations are strongly interconnected. Datasets for geometric morphometrics consist of 209 valves with landmarks distributed on the outer surface and margins. Results support morphological homogeneity of shell throughout the study area. There are important differences between datasets in their dimensionality and directional asymmetry. Pores/ridges dataset is highly unstructured with 50 + eigenvectors describing 90% of variation in PCA and with no directional asymmetry. Outline dataset is highly structured with 5 eigenvectors describing 90% of variation with strong directional asymmetry, with the right valve showing more variation in shape than the left valve. Although pore homologization could be difficult, these landmarks might be more powerful in multispecies geometric morphometric analyses, or multivariate analysis of environmental influences on the ostracod shell. Also different valves can easily be matched, which is very important for fossil species where often one valve is missing. Permutation tests show a statistically significant negative correlation between size and depth, but predicted values are small. Partial least square analyses of covariation between the outline and landmarks on the surface reveal integration of the two compartments but the covariation is not sufficient to account for all the variation throughout the valves.

Ostracod shell plasticity across longitudinal and bathymetric ranges

Pontocyprididae is a diverse ostracod family with over 300 species described so far. It has a worldwide distribution in various marine ecosystems. I describe two new species belonging to Ekpontocypris Maddocks, 1969 and Schedopontocypris Maddocks, 1969. They have been collected from shallow littoral and interstitial waters from the east coast of Korea. This is the first record of the family from this country. Two new species differ from their closest congeners mostly by male sexual characters, including morphology of the hemipenis and prehensile palps. Taxonomic keys to living representatives of Ekpontocypris and genera of Pontocyprididae are provided.

Two new Pontocyprididae (Ostracoda) species from Korea

The Australian Candonidae ostracod fauna has few surface water representatives, despite Australia being one of the principal centers of Candonidae biodiversity. The majority of Australian species live in subterranean waters, with most genera and one tribe being endemic to the continent. Species in Australia show Tethyan and Gondwana connections, with relatives living in European and Central/South American subterranean waters. I describe Hancockcandonopsis gen. nov. from boreholes in the alluvial aquifers of the Peel River and Hunter Valley, which at present contains five species, of which three are named, H. inachos sp. nov., H. io sp. nov., and H. tamworthi sp. nov., and two are left on the open nomenclature. All species are allopatric and short range endemics. The genus belongs to the almost cosmopolitan Candonopsini tribe, and the major generic autapomorphy is a hook-shaped h3-seta on the cleaning leg. Characters on the prehensile palps and hemipenis of Hancockcandonopsis indicate a close relationship with the Queensland genus Pioneercandonopsis Karanovic, 2005 and two West Indies genera, Cubacandona Danielopol, 1978 and Caribecandona Broodbaker, 1983. A cladistic analysis, based on 32 Candonopsini species and 24 morphological characters, is used to test phylogenetic relationships among Candonopsini genera globally. Several hypotheses about the historical biogeography of this tribe are discussed.

A new Candonopsini (Ostracoda) genus from subterranean waters of New South Wales (Australia)

Phylogeny and divergence times of Lake Baikal and subterranean candonid lineages

With 104 endemic species family Candonidae is one of the most diverse crustacean groups in Lake Baikal, yet their phylogenetic relationships and position in the family have not been addressed so far. Here, we study the phylogenetic position of Baikal candonids within the family and their evolutionary history using molecular markers for the first time since their original description. We choose 10 Baikal and 28 species from around the world, and three ribosomal RNA-s (18S, 28S, and 16S), and analyze individual and concatenated datasets using Bayesian Inference in MrBayes and BEAST. For molecular divergence time estimates, four fossil records are used to calibrate the root and three internal nodes. The 28S dataset is tested under the strict molecular clock, while for other data we use relaxed clocks. Resulting trees show incongruence between molecular and fossil divergence time estimates, with the former suggesting older ages. Strict molecular clock analysis results in narrower node age confidence intervals and younger time estimates than other analysis. All trees support at least two candonid lineages in Baikal, with two independent colonization events, and 28S suggests a major radiation between 12 and 5Mya. This divergence time estimate mostly agrees with another, unrelated, ostracod group in the lake and other lake animals as well. Baikal candonid clades show a close phylogenetic relationship with Palearctic lineages, but their deep divergence is indicative of separate genera. Results also suggest a monophyly of tribes that today live exclusively in subterranean waters, and we offer several hypotheses of their evolutionary history.

Phylogenetic position and age of Lake Baikal candonids (Crustacea, Ostracoda) inferred from multigene sequence analyzes and molecular dating

Pores and sensilla on ostracod shell have often been used in studies of ontogeny, taxonomy, and phylogeny of the group. However, an analysis of sexual dimorphism and variation between valves in the number and distribution of pores is lacking. Also, such studies have never been done on a widely distributed, morphologically variable, and weakly ornamented freshwater ostracod. Here, we survey pores in one such species, Physocypria kraepelini. We choose 27 homologous pores as landmarks for 2D-geometric morphometric analysis, with the aim to assess intersexual and between valves variation in size and shape relative to the Fourier outline analysis. This species has only simple (Type A) pores with and without a lip, and each pore carries an undivided sensory seta. Our results show that the total number of pores varies (from 270 to 296), but this is not associated with a specific valve. Males carry fewer pores than females, however no sex specific pores are found. Small intrapopulation divergence of the Cyt b molecular marker (1%) indicates that morphological variability is not species related. We found that P. kraepelini exhibits directional asymmetry of size and shape, sexual size dimorphism (SSD) but lacks sexual shape dimorphism (SShD). Two geometric morphometrics methods were congruent in the estimation of SSD, SShD, and directional asymmetry of shape but differ in the statistical evaluation of directional asymmetry of size. Contrary to other animal groups, our study suggests that ostracods have more pronounced directional asymmetry of shape compared to directional asymmetry of size.

A complete survey of normal pores on a smooth shell ostracod (Crustacea): Landmark-based versus outline geometric morphometrics

Manuelcypris n. gen., along with two species M. chetumalensis n. sp. and M. tabascena n. sp., are described from Southern Mexico. Another three species are transferred into the new genus: M. cisternina (Furtos, 1936) comb. nov., known from the Yucatan Peninsula, was originally described in the genus Eucypris Vavra, 1891, while M. punctata (Keyser, 1975) comb. nov., from Florida, and M. antillensis (Broodbakker, 1982) comb. nov., from the West Indies, were originally described in the genus Heterocypris Claus, 1892. The latter two new combinations are based only on the literature data, while for M. cisternina we examined its type material. The new genus is attributed to Cyprinotinae, but with an isolated position based on the absence of any seta on the basal segment of the walking leg and the reduced chaetotaxy of the fifth leg. The validity of this genus is confirmed with molecular markers, 18S rDNA and 28S rDNA which were used in the phylogenetic reconstruction along with several newly obtained sequences and others downloaded from the GenBank belonging to closely related taxa. Two methods, Maximum Parsimony and Maximum Likelihood, used in the analysis support the new genus with 100 bootstrap values. We also provide a taxonomic key for the five representatives of the new genus.

A new freshwater ostracod genus from the northern Neotropical region and its phylogenetic position in the family Cyprididae (Podocopida)

Family Candonidae is one of the most diverse freshwater ostracod groups in terms of number of taxa and ecological adaptations. The family is especially well represented in the subterranean waters around the world, with many species being short-range endemics. Here we describe four new species, Undulacandona koreanasp. nov., U. aeolussp. nov., U. andromedasp. nov. and U. cetussp. nov., from two localities in the central part of South Korea. One more species, Undulacandona sp., is briefly reported here, but not described because of the absence of adults. The mtCOI sequence obtained from Undulacandona sp. and its closest relative, U. koreana, supports a separate species status. Undulacandona Smith, 2011 was previously known only from two species from Japan. A peculiar looking Zenker organ, hemipenis, and uropodal ramus of the six Undulacandona suggest an isolated position in the family Candonidae. Here we use 28S and 18S rRNA to reconstruct phylogenetical relationships within candonid ostracods, but also between the three closely related families: Candonidae, Cyclocyprididae and Paracyprididae. We sample 30 species and use three methods to reconstruct the phylogenetic relationships: Bayesian inference, maximum likelihood and maximum parsimony. None of the methods and neither of the markers clearly resolve the interfamily relationships. However, the family Candonidae is always supported with highest bootstrap values and posterior probabilities, as is a sister relationship between Undulacandona and Cryptocandona Kaufmann, 1900. Our results also indicate the need for a revision of Paracyprididae, as well as the polyphyletic nature of the genus Fabaeformiscandona Krstic, 1972. We also recognize potential misidentifications on GenBank. Finally, we also provide a taxonomic key to Undulacandona species.

Phylogenetic position of the East Asian ostracod genus Undulacandona within Candonidae with description of four new species from subterranean waters of Korea

We briefly report the observation of five ostracod species: Scottia birigida Smith, Matzke-Karasz, Kamiya and Ikeda, 2002; Codonocera mortenseni Poulsen, 1962; Pyrocypris noctiluca Kajiyama, 1912; Euconchoecia cf. chierchiae Muller, 1890; and E. pacifica Chavtur, 1976. All five species are new records of Korean ostracod fauna. Specimens were collected during the 2014-2016 Korean Indigenous Species project. For three species we also include mtCO1 sequences. Currently, there are 65 published reports of indigenous Korean ostracod species.

Five new records of ostracods (Crustacea) from Korea

This study describes a new species of cytheroid ostracod, Paradoxostoma koreana sp. nov., collected in Korea. In addition, three other cytheroid ostracods, P. setoense Schornikov, 1975, Loxoconcha pulchra Ishizaki, 1968, and Ishizakiella miurensis (Hanai, 1957), are reported with brief descriptions and images. Paradoxostoma setoense and L. pulchra were previously only known from Japan, while I. miurensis was previously reported from Korea. Here, we describe variability in hemipenis morphology observed in the Korean population. The new species is closely related to several East Asian species, but its sister species is P. rhomboideum Okubo, 1977. The primary difference between the new species and P. rhomboideum is morphology of the distal projections of the hemipenis, but minor differences exist in the details of the cheatotaxy of other appendages. This report also provides a list of all East Asian Paradoxostomatidae

One new species and three records of cytheroid ostracods (Crustacea, Ostracoda) from Korea

With almost 200 species described from all over the world, Polycope Sars, 1866 is the most specious and eurytopic genus of the exclusively marine family Polycopidae. Unlike other members of the subclass Myodocopa, polycopids are commonly found in fossiliferous rocks from strata as old as the Carboniferous, which makes them a useful tool in palaeoenvironmental reconstructions. The genus Polycope in particular is an opportunistic group and can putatively serve as an indicator of organic rich, fine grained sediment, reduced sea ice, and increased productivity, which is especially important when correlating biological data with the Quaternary climate changes that often requires accurate generic and species identifications. Polycopid taxonomy is relatively complicated because species tend to have conservative shell shapes and the soft body is extremely reduced, which can lead to numerous misidentifications, especially when fossil and Subrecent taxa are mixed and the shell is the only available source of taxonomic information. Here we study Polycope species collected during the first cruise of the IceAge project from the margin off Iceland. In total, four species have been recovered from 200 to 2747m depth. They have been identified as P. pseudoinornata Chavtur, 1983, P. punctata Sars, 1869, P. yasuharai sp. nov., and P. sp. This is the first time since the middle of the 19th century that members of this genus have been studied in the North Atlantic and Arctic using both their soft parts and shells. It allowed us to reconsider numerous previous records of Polycope from this region. Beside a critical overview of the polycopid diversity in the North Atlantic and Arctic, and detailed taxonomic (re)descriptions of the newly collected specimens, we also provide maps of their distributions, analyse their ecological preferences, and offer a preliminary phylogeny of the North Atlantic species of Polycope based on 28S rDNA sequences.

The genus Polycope (Polycopidae, Ostracoda) in the North Atlantic and Arctic: taxonomy, distribution, and ecology

The ostracod genera Parapolycope Klie, 1939 and Kliecope Tanaka, Tsukagoshi & Karanovic, 2014 have a sexually dimorphic upper lip, and males use their lip during courtship. Here we study the male upper lip of 14 species in order to find homologous structures. For this purpose, the lip is divided into six homologous parts, determined by their relative position on the lip and the lip's position in relation to other body parts. We found that the distal part ('c') is the most variable across taxa, probably due to high sexual selection. Six characters of the male upper lip are used in our cladistic analysis, along with another 12, in order to study phylogenetic relationships between Parapolycope species from East Asia. In addition, 18S rRNA is used to reconstruct molecular phylogeny and test the congruence between morphological and molecular data. The recovered topology on all obtained trees is almost identical, emphasising the importance of the male upper lip morphology in interpreting phylogenetic relationships in this peculiar ostracod group. Parapolycope viriosa, sp. nov. and P. widoensis, sp. nov. from marine interstitial habitats in South Korea are described here. To aid further identification of the 12 East Asian Parapolycope species we provide a taxonomic key.

Congruence between male upper lip morphology and molecular phylogeny in Parapolycope (Ostracoda), with two new species from Korea

Uncoupling between molecular and morphological evolution is common in many animal and plant lineages. This is especially frequent among groups living in ancient deep lakes, because these ecosystems promote rapid morphological diversification, and has already been demonstrated for Tanganyika cychlid fishes and Baikal amphipods. Ostracods are also very diverse in these ecosystems, with 107 candonid species described so far from Baikal, majority of them in the genera Candona Baird, 1845 and Pseudocandona Kaufmann, 1900. Here we study their morphological and molecular diversity based on four genes (two nuclear and two mitochondrial), 10 species from the lake, and 28 other species from around the world. The results of our phylogenetic analysis based on a concatenated data set, along with sequence diversity, support only two genetic lineages in the lake and indicate that a majority of the Baikal Candona and Pseudocandona species should be excluded from these genera. We describe a new genus, Mazepovacandona gen. n., to include five Baikal species, all redescribed here. We also amend the diagnosis for the endemic genus Baicalocandona Mazepova, 1972 and redescribe two species. Our study confirms an exceptional morphological diversity of Lake Baikal candonids and shows that both Baikal lineages are closely related to Candona, but only distantly to Pseudocandona.

Morphological and molecular diversity of Lake Baikal candonid ostracods, with description of a new genus

subterranean ostracods: diversity, zoogeography, and phylogeny

Genus Hemicytherura (Ostracoda: Podocopida: Cytheruridae) from Hujung Beach, Korean East Coast

Individual wood fragments obtained from Agassiz trawl samples in the abyssal plain area off the Kuril- Kamchatka Trench were analysed for faunistic components. Out of seven pieces of wood collected, only five harboured fauna and each showed distinctively different colonization patterns. In total, 257 specimens, mainly belonging to the phyla Arthropoda, Nematoda, Mollusca and Annelida, were collected from the available pieces of wood. While wood-boring bivalves of the genus Xylophaga, generally seen as opportunists among wood-converting organisms, were present at nearly all stations, the overwhelming majority of taxa found were restricted to individual pieces of wood. A fresh piece of wood from a site opposite to the Tsugaru Strait, was the most heavily colonized. The presence of shallow or even putative fresh-water taxa beside truly deep-water components possibly suggests a recent sinking of that particular wood fragment and demonstrates the role of such ephemeral organic objects in deep-sea ecosystems as energy-rich feeding grounds and potential distributional stepping stones. Detailed studies of driftwood communities on single sunken wood fragments from deep oceans are limited. The present data not only demonstrate a tolerance of some taxa to changes in physical parameters, such as hydrostatic pressure, salinity and temperature, but also indicate a higher biodiversity on fresher wood pieces compared to wood which already underwent decomposition processes. It is, however, not clear whether the species diversity was linked to the type of wood, since exhaustive analyses on the wood pieces themselves were not conducted.

Wood-associated fauna collected during the KuramBio expedition in the North West Pacific

Ostracods are drastically reduced crustaceans, with never more than eight appendages enclosed between two valves, leaving only a limited number of morphological characters for species delineation. Conservative morphology of characters used to define genera, along with high variability of characters used to define species are creating problems in applying a morphospecies concept. A high intraspecific variability in a Lake Biwa (Japan) endemic, Physocypria biwaensis (Okubo, 1990), has been observed previously but was never studied in detail. Two sympatric forms, differing in pigmentation and size, suggest a presence of reproductive isolation. The aim of this study is to employ molecular and morphometric tools to aid in species delineation within P. biwaensis complex and reconstruct their phylogenetic relationships. A fragment of the mtCOI gene was amplified from 30 specimens, and an additional 37 specimens were studied for morphological characters. Resulting phylogenies showed that each morphologically distinct form is associated with a distinct phylogenetic group based on mtDNA. The average pairwise distance is very low (5%), indicating a recent divergence time. I speculate that there is a possibility that one of them originated in the lake, while the other probably colonized it afterwards. This seems to be supported with an apparent niche partitioning at different depths. In spite of the fact that traditionally used sexual characters are highly variable in these two species, the morphometric analysis of shell and soft part related characters clearly delineates them and suggests that such characters may be useful for future detection of seemingly cryptic ostracod species.

Barcoding of Ancient Lake Ostracods (Crustacea) Reveals Cryptic Speciation with Extremely Low Distances

Stimulated by finding a novel cytheroid ostracod in a piece of sunken wood retrieved from the sea-bed in the Kuril-Kamchatka Trench, we have reviewed all previously published data on ostracods from similarly ephemeral deep-sea habitats (wood falls, hydrothermal vents and cold seeps). These data are placed in the context of all data on living, deep-sea ostracods from other environments. We confirm previous authors' conclusions that faunas from these ephemeral habitats are similar at the generic level, and include elements common to shallow and deep habitats. However, at the species level, endemism varies from zero at cold seeps, to 35% in wood falls and 60% at hydrothermal vents, which is an indication of the relative longevity of these habitats. Non-endemic species occur also in oligotrophic, deep-sea sediments but not in shallow environments. This is in contradiction to previous assumptions that these ephemeral faunas share more species and with shallow habitats than genera with the oligotrophic, deep-sea sediments. We agree with previous authors that the dispersal strategy of wood fall, vent and seep ostracods includes hitchhiking and we propose that it also includes the ability to survive ingestion by larger, more motile animals. The homogeneity of the faunas from ephemeral habitats collected off the American continent is in stark contrast to the highly endemic fauna found in Northwestern Pacific. This suggests that the ostracods may have biogeographical patterns similar to those previously proposed for other groups of benthos. However, any proposal for a global biogeographical scheme for ostracod distributions will have to await far more comprehensive coverage from presently unstudied regions. Finally, we describe and name a novel species of ostracod from the wood fall collected at a depth of 5229 m in the abyss east to the Kuril-Kamchatka Trench, Northwestern Pacific; erecting a new family Keysercytheridae fam. nov. and a new genus, Keysercythere gen. nov., to accommodate it, and name it, Keysercythere enricoi sp. nov. We present a preliminary key to all Cytheroidea families for which living representatives have been described.

Biogeography of deep-sea wood fall, cold seep and hydrothermal vent Ostracoda (Crustacea), with the description of a new family and a taxonomic key to living Cytheroidea

Previous studies have suggested incongruence between current systematics and molecular phylogenies of Sarsielloidea, with a possible polyphyly of the family Philomedidae. Here, we provide molecular phylogenetic analyses based on 18S rDNA and 28S rDNA. The former includes five new sequences and 12 from the GenBank, and the latter two new and six sequences from the GenBank. We use three methods, maximum likelihood, maximum parsimony, and neighbor joining, and all reconstructed phylogenies support previously suggested polyphyly, indicating a closer relationship of the subfamily Pseudophilomedinae with one subfamily of Sarsiellidae than with the nominotypical subfamily of Philomedidae. Morphological characters that may be key indicators of the phylogenetic relationships between three Sarsielloidea families are discussed. We also describe the 21st representative of the Pseudophilomedinae genus, Harbansus Kornicker, (Smith Contrib Zool 260:75, 1978), Harbansus ningalooi n. sp., from the Ningaloo Reef, Western Australia. This is the first Harbansus reported from the Australian west coast and the second from the Australian coral reef systems. It differs from all other congeners by peculiar claw-like processes on the posterior infold. Most Harbansus species have relatively restricted distributions, except Harbansus paucichelatus (Kornicker, in Inst Mar Sci 5:195-300, 1958), which has also been postulated to represent a species complex. We present a detailed morphological redescription of this species, based on the freshly collected material from the Yucatan Peninsula, as well as four mitochondrial COI sequences. These become the first COI sequences of the entire superfamily Sarsielloidea available on the GenBank. To facilitate future identification, we include a key to species of Harbansus.

On the phylogenetic position of Pseudophilomedinae within Sarsielloidea (Ostracoda, Myodocopida), with a description of one new Harbansus from Ningaloo Reef and redescription of H. paucichelatus from Yucatan

Candoninae is by far the most diverse ostracod group in subterranean habitats, with many genera which today have no surface water representatives. This subfamily is also peculiar because species tend to have restricted distributions regardless of habitat type, and, unlike other non-marine ostracod lineages, extremely rarely reproduce parthenogenetically. Nannocandona faba Ekman, 1914 is an exception, being originally described from Sweden, but then reported throughout the Holarctic. We study morphological variability of this species here, both based on old museum specimens and on freshly collected material. We propose that the name should only be restricted to the Swedish population, and we describe two new subterranean species: Nannocandona danielopoli n. sp. from Austria, and Nannocandona schornikovi n. sp. from South Korea and the Russian Far East. These descriptions allow us to evaluate records of N. faba in other parts of the Holarctic. A new map of the genus distribution is proposed, as well as a key to species identification. Parthenogenetic reproduction of Candoninae and their general ecology is also discussed.

Zoogeography of the ostracod genus Nannocandona (Podocopa) with description of two new species from Europe and East Asia

The East China Sea is part of the Warm Temperate Northwest Pacific zoogeographic province and, as such, has a high biodiversity and many tropical and subtropical biotic elements. Nevertheless, many invertebrate groups from this area remain poorly studied. Ostracods are one of them, especially those belonging to the subclass Myodocopa. In this paper we provide the first data on a diverse myodocopid family, Sarsiellidae, not only for the East China Sea, but also for Korea. Five species are reported in this paper from three Korean islands (Jeju, Chuja, and Maemul), and they are only a part of the ostracods collected during this study, indicating a high diversity of the group in this region. Three new species, Eurypylus koreanus sp. nov., Eusarsiella hanguk sp. nov., and Sarsiella nereis sp. nov., clearly stand apart from their respective congeners, mostly by prominent shell characters but also by details of the soft part morphology. Their affinity though clearly indicates a close connection of the region with the more southern zoogeographical realms, especially Central Indo Pacific and partly Temperate Australasia. Two species previously known from Japan (north part of the Sea of Japan and southeastern part of the Pacific Coast of Japan), Sarsiella japonica Hiruta, 1977 and S. misakiensis Kajiyama, 1912, are redescribed. Based on 11 newly obtained COI sequences we construct a preliminary phylogenetic tree, which supports previous hypotheses based on the morphological data, that Eusarsiella Cohen & Kornicker, 1975 is a polyphyletic taxon. With the maps of species distribution provided for each of the three genera, we give an overview of their current zoogeography, and clearly indicate areas that have no data, mostly due to the lack of investigation.

Five Sarsiellidae ostracods (Crustacea: Myodocopida) from the South Coast of Korea (East China Sea)

Barcoding of ancient lake ostracods (Crustacea) reveals cryptic speciation with extremely low distances

Diversity and zoogeography of the South Korean Ostracoda (Crustacea, Ostracoda): current knowledge and perspectives

Barcoding of ancient lake ostracods (Crustacea) reveals cryptic speciation with extremely low divergence

Diversity and Zoogeography of the South Korea Ostracods (Crustacea, Ostracoda): Current Knowledge and Perspectives

Cuticular organs have not been described systematically in harpacticoids until recently, and they have never been used as characters for reconstructing phylogenetic relationships in any crustacean group. We survey cuticular pores and sensilla on somites in ten Miraciidae species, belonging to six genera, from Korea, Australia, and Russia. Nine species belong to the subfamily Stenheliinae, while the outgroup belongs to the subfamily Diosaccinae. We aim to compare phylogenetic trees reconstructed for these harpactioids based on: 1) cuticular organs (with 76 characters scored, 71% of them phylogenetically informative); 2) traditionally used macro-morphological characters (66 scored, 77% of them informative); and 3) mtCOI DNA data. All analyses suggest that cuticular organs are useful characters for harpacticoid species delineation, although not as sensitive as some fast-evolving molecular markers. Reconstructed cladograms based on all three datasets show very high bootstrap values for clades representing distinct genera, suggesting that cuticular organs are suitable characters for studying phylagenetic relationships. Bootstrap values for the more basal nodes differ among the different cladograms, as do the sister-group relationships they suggest, indicating that cuticular organs probably have different evolutionary constraints from macro-morphological characters. Cuticular organs could be quite useful in the study of old museum specimens and fossil crustaceans.

Suitability of cuticular pores and sensilla for harpacticoid copepod species delineation and phylogenetic reconstruction

Family Polycopidae is one of the more abundant and diverse taxa occurring in marine interstitial environments. Most of the interstitial polycopids are so far known from Japan and belong to the genus Parapolycope Klie, 1936. In this paper we describe another four new species from Japan. A new genus, Kliecope gen. nov. is erected to include one new species Kliecope mihoensis sp. nov. and one new combination Kliecope oligohalina (Tanaka Sz Tsukagoshi, 2010) comb. nov. Although the morphology of Kliecope is similar to Parapolycope, the new genus has the following diagnostic characters: absence of an inward bulge on the antennular second podomere, presence of two setae bearing a sucker on the antennular third podomere, and absence of a dorsal seta on the basis of mandibula. Another three Parapolycope, Parapolycope setouchiensis sp. nov., Parapolycope subtidatis sp. nov., and Parapolycope miurensis sp. nov. are described as well. To test the phylogenetic relationship between the new genus and Parapolycope, we performed playlogenetic analyses based on the 14 18S rDNA sequences of interstitial Polycopidae species, 12 of which were newly obtained from our material. The 18S gene proved to be suitable for phylogenetic analyses in polycopids with high intraspecific or intrageneric resolution. Here we present trees obtained with maximum n likelihood, maximum parsimony, and neighbour-joining methods, and they support the divergence between Kliecope and Parapolycope with high bootstrap values.

Molecular phylogeny of interstitial Polycopidae ostracods (Crustacea) and descriptions of a new genus and four new species

Contrary to earlier beliefs, crustaceans are present in ice-covered lakes of Antarctica. Interpretation of the significance of this has been hampered by the absence of robust identification of taxa present. We examine cyclopoid copepods from three widely separated lakes. All belong to the michaelseni group of the genus Diacyclops, which is widespread across Continental Antarctica, but do not fit into any existing species. Two new species were identified from eastern Antarctica, D. walkeri from Pineapple Lake (Vestfold Hills) and D. kaupi from Transkriptsii Gulf (Bunger Hills). Most significant was a dense population of a new epibenthic species (D. joycei) associated with microbial mats in Lake Joyce, one of the smaller McMurdo Dry Valleys lakes. This represents the first record of adult cyclopoid copepods from the ice-covered lakes of the Transantarctic Mountains. Continental Antarctica is the centre of diversity for this group of crustaceans and we argue that this is better explained by persistence through past glacial advances rather than by recent post-glacial colonization. The existence of a species endemic to Lake Joyce but apparently absent from other Dry Valleys lakes is discussed in relation to our understanding of the history of the McMurdo Dry Valleys lakes and their faunas.

Diacyclops (Copepoda: Cyclopoida) in Continental Antarctica, including three new species

Euryte koreana sp. nov. is described from the shallow littoral on the East Coast of South Korea, and represents the first record of the subfamily Euryteinae Monchenko, 1974 in the Pacific Ocean north of the tropics. It belongs to a group of species that have the caudal rami length/width ratio of around four, but differs from all congeners by a number of morphological features. Detailed drawings and extensive scanning electron micrographs of many characters of ornamentation provided for this species should serve as a benchmark for distinguishing closely related species in this subfamily with conservative macro-morphology. A morphologically distinct population from anchialine caves in Mallorca, identified previously as Euryte longicauda Philippi, 1843, is described as another new species: Euryte jaumei sp. nov. To test the phylogenetic relationships of its members and previous hypotheses about generic placement of two species associated with scleractinian corals, several cladistic analyses are performed on all 16 currently recognized species of Euryteinae and two outgroups, Neocyclops australiensis Karanovic, 2008 and Troglocyclops janstocki Rocha and Iliffe, 1994, using 25 morphological characters. All resulting trees suggest a close relationship between the two commensal species and them as a sister clade to all other Euryteinae. They are transferred into a newly erected genus Coraleuryte gen. nov., as C bellatula (Humes, 1991) comb. nov. and C. verecunda (Humes, 1992) comb. nov., and a revised diagnoses is provided for the genus Euryte Philippi, 1843. Obtained cladograms also show that Ancheuryte Herbst, 1989 is nested deeply within the Euryte clade, so the genus is synonymized and its only species is transferred, as E. notabilis (Herbst, 1989) comb. nov. A key to species of Euryteinae is also provided.

On the phylogeny of Euryteinae (Crustacea, Copepoda, Cyclopoida), with description of one new species from Korea

A new species of the genus Chrissia Hartmann, 1957 is described from Dongqian Lake, East China. Chrissia dongqianhuensis n. sp. is characterized by short swimming setae on the second antenna. This character state is very rare in the genus, and besides the new species the feature is found only in Chrissia ceylonica (Daday, 1898). The two species can be distinguished from each other based on the shell shape: C. ceylonica has distinctly protruding posterior end with sinusoid postero-dorsal margin, while in C. dongqianhuensis the postero-dorsal margin is evenly rounded and the posterior end is not protruding. In addition, C. dongqianhuensis has only 5 swimming setae. Chrissia presently contains 35 living species. In order to assess the position of the new species within the genus and the position of Chrissia within Cyprididae, we analyzed morphological data and nucleotide sequences for 18S rDNA. A total of 18 morphological characters for 32 species were used. Molecular data include sequences from 29 species (18 from the GenBank, 11 newly obtained) belonging to several lineages of Cyprididae and Ilyocyprididae. Analysis of the morphological characters resulted in 16 equally parsimonious trees with several well-supported lineages, such as the African-Indian lineage of Chrissia with pointed extensions on their shells, and a predominantly Asian lineage with low shells with rounded margins. The molecular phylogeny suggests that Herpetocypridinae is polyphyletic and in need of revision, and also indicates that some sequences from the GenBank are probably misidentified. High bootstrap values support Cypridopsinae, Cypricercinae, and Dolerocypridinae, while Cyprinotinae seems to be polyphyletic.

PHYLOGENY OF THE GENUS CHRISSIA (OSTRACODA: CYPRIDIDAE) WITH DESCRIPTION OF A NEW SPECIES FROM CHINA

Sarsiellidae (Myodocopida, Sarsielloidea) fauna from Korea

The genus Paradoxostoma (Ostracoda: Podocopida: Paradoxostomatidae) from South Korea, with description of one new species

A new genus of Cyprididae ostracods from the Yucatan Peninsula

A new ostracod family (Crustacea) collected from driftwood in the Kuril-

A new species of the genus Coxicerberus (Crustacea: Isopoda) from several localities in Korea and their molecular diversity

Barcoding of ancient lake ostracods reveals cryptic speciation with extremely low divergence rates

Gomphodella De Deckker, 1981 belongs to the subfamily Timiriaseviinae, and it inhabits almost exclusively subterranean waters of Western Australia. We describe the ninth species of the genus, G. alexanderi sp. nov., from bore-holes in the Pilbara region. The species is closely related to G. yandii Karanovic, 2009 and G. quasihirsuta Karanovic, 2009, but can be distinguished by its shell morphology, appearance of the hemipenis, and chaetotaxy of the antenna. We also report on G. yandii and G. cf. martensi Karanovic, 2009, collected sympatrically with the new species, indicating some new characters not mentioned in the original descriptions. We show for the first time that Gomphodella has an inverse lophodont hinge, instead of a lophodont one as previously believed. The significance of the hinge structure, sulci, and other shell characters in the systematics of Timiriaseviinae are discussed. In addition, the posterior extension on the female body, the so-called 'forked organ', is here reported for the first time in the genus Gomphodella. Because these characters provide a new insight into the phylogenetic relationships of Timiriaseviinae we performed two cladistic analyses: one including only nine genera with living representatives, the other including 17 genera. They resulted in one and 23 equally parsimonious trees respectively. Inclusion of the fossil taxa significantly changes the tree topology, but on both trees the Gondwanan lineage, Cytheridella Daday, 1905/Gomphocythere Sars, 1924/Gomphodella is strongly supported, as well as a close connection between the South American semi-terrestrial and some fossil genera. Another well-supported clade is formed by the genera Kovalevskiella Klein, 1963, Frambocythere Colin, 1980 and Rosacythere Colin, 1980. Maps of distribution of Recent genera and geological age of Timiriaseviinae are also presented here.

Phylogeny and diversity of Timiriaseviinae ostracods (Podocopida, Cytheroidea) with description of one new species from arid Western Australia

Limnocytherina is a genus conformed by 12 species; its distribution in the American continent is known to be exclusively on the North (neartics), but little is reported about its distribution from Mexico (transition zone) and Central America (Neotropics). Different sampling campaigns were undertaken in three crater lakes from the Axalapascos region in east-central Mexico, during 2008, 2009 and 2011. As a product of these campaings, the new species of Limnocytherina axalapasco was found, which displays some intraspecific variability among populations. In this study, we described the taxonomy, the habitat, the ecological preferences and the larval development of this new species. A total of 10 sediment samples (8 littoral, 2 deepest point) were collected from lakes Alchichica, La Preciosa and Quechulac. We found that L. axalapasco is closely related to two North American species: L. posterolimba and L. itasca as well as one Central American species L. royi comb. nov. With the inclusion of L. axalapasco and L. royi to the genus, the distribution of Limnocytherina is extended to Central America. The four most important distinguishing characters of this new species are: 1) valve surface and margins covered with small, spine-like projections; 2) most of the A1 setae with a highly developed setule at distal part, producing a bifurcate appearance; 3) the upper ramus on the hemipenis is elongated, and by far overpasses dorsal/distal margins, distal lobe is triangular and short, while the hook-like process is prominent, outward orientated, and overpassing the tip of the distal lobe; 4) the UR is moderately developed with seta f3 elongated and setae f1 and f2 short. Considering its ecological characteristics and larval development, L. axalapasco was preferably found in alkaline waters dominated by Cl- or HCO3- and Na+ or Mg2+, temperatures ranging between 19.1 to 20.3 degrees C, and dissolved oxygen concentrations from 5 to 6.5mg/L. This species was abundant in deeper (similar to 64m) areas of the saline Alchichica lake, where surface water displayed conductivity values of up to 2 250 mu S/cm, and the sand with low percentage of silt resulted the preferred substrate. Along with the description of L. axalapasco, we provide additional information on the hemipenis of L. itasca, L. royi and L. sanctipatricii, and we discuss on the Limnocytherina-type of hemipenis.

On Limnocytherina axalapasco, a new freshwater ostracod (Podocopida: Limnocytheridae) from Mexican crater lakes

Polyphyly of the genus Delavalia Brady, 1869 has been postulated previously based on intuitive methods, but no phylogenetic study was ever conducted. A chance discovery of seven sympatric species of this genus in the highly industrialized Gwangyang Bay in South Korea, in addition to one species each from the closely related genera Stenhelia Boeck, 1865 and Onychostenhelia Ito, 1979, prompted a renewed interest in the phylogenetic relationships within the subfamily Stenheliinae Brady, 1880. Additional surveys along the Korean coast failed to produce Delavalia species, but comparative material was sourced from Posyet Bay in the Russian Far East. Aims of this study were to reconstruct phylogenetic relationships of the newly collected stenheliins using molecular methods, test the hypothesized polyphyly of Delavalia, formally describe any resulting monophyletic units, perform a comparative study of traditional morphological and novel micro-morphological characters, and describe all new Delavalia species. A fragment of the mtCOI gene was successfully PCR-amplified from 23 stenheliin specimens and an additional 300 specimens were studied for morphological characters. All phylogenetic analyses supported the presence of at least eight genetically divergent lineages, most with very high bootstrap values, and the polyphyletic nature of Delavalia is demonstrated. Three new genera, each supported by molecular data and a number of morphological synapomorphies, were erected to accommodate the newly discovered species and some previously described members of Delavalia: Wellstenhelia gen. nov., Itostenhelia gen. nov., and Willenstenhelia gen. nov. The Chinese Wellstenhelia qingdaoensis (Ma & Li, 2011) comb. nov. is recorded for the first time in Korea, and six new species are described from Gwangyang Bay: Wellstenhelia calliope sp. nov., Wellstenhelia clio sp. nov., Wellstenhelia erato sp. nov., Wellstenhelia euterpe sp. nov., Itostenhelia polyhymnia sp. nov., and Willenstenhelia thalia sp. nov. Additonally, Itostenhelia golikovi (Chisleno, 1978) comb. nov. is redescribed from newly collected material from the type locality in Russia and its male described for the first time, while Wellstenhelia melpomene sp. nov., Willenstenhelia urania sp. nov., and Willenstenhelia terpsichore sp. nov. are established as new names for previously reported populations of two presumably widely distributed Delavalia species.

New insights into polyphyly of the harpacticoid genus Delavalia (Crustacea, Copepoda) through morphological and molecular study of an unprecedented diversity of sympatric species in a small South Korean bay

A new species of Parapolycope (Crustacea, Ostracoda, Polycopidae) from Korea

Diversity and phylogeny of Polycopidae (Ostracoda, Myodocopa), with a special reference to the deep sea

Taxonomic study of the genus Paradoxostoma (crustacea, Ostracoda, Paradoxostomatidae) from South Korea

The first report of the Genus Paradoxostoma (Ostracoda: Podocopida: Paradoxostomatidae) from Korean East Coast

Candoninae is the most diverse group of freshwater ostracods with over 300 living species described from all around the world. However, only 11 species have been reported from South Korea. Considering abundant freshwater ecosystems here this number is very low. It is no wonder that newly collected samples of freshwater meiofauna often contain Candoninae ostracods which are new records for South Korea, or new taxa. Earicandona mounchyon gen. nov. sp. nov. and Typhlocypris (Pseudocandona) pratensis (Hartwig, 1901) were collected from two open freshwater bodies in Gangwon-do, and Gyeongsangbuk-do in South Korea. The new genus is most closely related to the breuili-group of Fabaeformiscandona Krstic, 1972. The most important apomorphic character of the new genus is a hemipenis with a poorly sclerified lobe "g", and prehensile palps with more rounded dorsal margins. Beside the new species, Earicandona contains only E. okuboi (Smith & Janz, 2008) comb. nov. from Lake Biwa. This species was originally described in Fabaeformiscandona, fabaeformis-group. They differ mostly in the morphology of the shell, but also some details of soft body, including the more pronounced genital process in the Korean species. Typhlocypris pratensis was so far known from Europe and this finding significantly broadens its area of distribution. Both Typhlocypris and Earicandona belong to the tribe Candonini and the key to the genera of this tribe is also presented here.

Earicandona, new genus and the first record of Typhlocypris pratensis (Crustacea, Ostracoda) from South Korea

Polycopids are one of the most diverse and often very abundant ostracod group in the deep sea. The true diversity of polycopids today inhabiting this environment, however, is very poorly known, because most of the studies identify ostracod material to the genus level, and they are based on the shell characters only. In this paper we describe Pseudopolycope (Pseudopolycope) andeep sp. nov. collected during the ANDEEP-SYSTCO I expedition in 2007 in the Atlantic Sector of the Southern Ocean. The new species was collected from 2,063 m depth. It differs from other 18 Recent Pseudopolycope Chavtur, 1981 species by (1) a peculiar morphology of the structures between claws on the uropodal lamellae; (2) morphology of the mandibular exopod; and (3) ornamentation of the shell. This is the first description of a living polycopid species from the deep Southern Ocean.

Pseudopolycope (P.) andeep sp nov from the deep Southern Ocean (Crustacea, Ostracoda, Cladocopina)

Parapolycope Klie, 1936 belongs to the family Polycopidae, one of the ecologically most diverse and morphologically most primitive ostracod families. Due to the small size of animals, polycopids are poorly studied and unknown in many regions of the world. We describe a new species, Parapolycope koreana sp. nov., from marine beach interstitial in Gyeongsangnam-do, South Korea. This is the first representative of the genus, and the first named polycopid species from Korea. It is very closely related to several species from marine interstitial in Japan, but differs mainly in the shape and ornamentation of the shell and morphology of the male upper lip. A cladistic analysis of the genus Parapolycope is performed to test the phylogenetic relationships between species. Although Parapolycope presently encompasses 18 species, only 15 are included in the analysis, because Parapolycope seridentata (Hartmann, 1959), Parapolycope ramunchensis (Hartmann-Schroder and Hartmann, 1962), and Parapolycope minutissima (Hartmann, 1974) differ so much from other congeners that they should be excluded from the genus. The analysis is based on 27 morphological characters, with Parapolycopissa rossica (Chavtur, 1977) and Polycopiella microdentata Chavtur, 1979 as two outgroup taxa. In spite of the fact that descriptions of almost half of species included in the analysis are based on a limited set of morphological characters, the majority rule of the 15 equally parsimonious trees undoubtedly shows that there are at least two distinct lineages in the genus, defined by the number of claws on the female uropodal lamellae. A close relationship between the new species and the Japanese congeners is also strongly supported. We redescribe the type species of the genus, Parapolycope germanica Klie, 1936, based on the type material, and designate the lectotype and paralectotypes. A key for identification of Parapolycope species is provided, along with a map of their distribution. This is a cosmopolitan taxon, with the centre of diversity in the Northwest Pacific region.

Ostracod genus Parapolycope (Crustacea): Diversity, distribution, and phylogeny, with description of the first representative from Korea

Three new species of the genus Cypretta Vavra, 1985 are described from Southern Mexico, representing the first record of the genus in the country. Cypretta campechensis n. sp. is closely related to Florida and North Carolina species such as C. nigra Furtos, 1936, C. brevisaepta Furtos, 1934 and C. bilicis Furtos, 1936. Cypretta spinosa n. sp. is related to the North and South American species C. intonsa Furtos, 1936 and C. vivacis Wurdig & Pinto, 1993, but also to some Australian and South-East Asian Islands ones, such as C. obfuscata Victor & Fernando, 1981 and C. raciborskii (Grochmalicki, 1915). The last species described herein, Cypretta maya n. sp., is closely related to the South-East Asia islands, Australian and north Indian species, in particular to C. hirsuta Henry, 1923, C. longidactyla Victor & Fernando, 1981, and C. patialensis Battish, 1982.

On three new species of Cypretta Vavra, 1895 (Crustacea: Ostracoda) from the Yucatan Peninsula, Mexico

"Their story began 500 million years ago, but we only started to get to know them in 1746, when Linn? described the first ostracod species. Vividly portraying the freshwater ostracods, this comprehensive reference work gathers the knowledge gained during some 250 years, but which to date has remained scattered throughout the literature. It starts with an introduction to the class Ostracoda with a special focus on freshwater ostracods and highlights practical methods in their study. The systematic part includes an introduction to all families; identification keys for all subfamilies, genera and species; diagnoses for each subfamily and genus; and lists of synonyms and distribution of species. The text is richly illustrated with distribution maps, line drawings of key generic characteristics, and numerous SEM photographs. Serving as an excellent starting point for all further research on freshwater ostracods, it can be widely used not only by ostracodologists, but also by crustaceologists, evolutionists and ecologists.

&quot;Recent freshwater ostracods of the world: Crustacea, Ostracoda, Podocopida

Two new Thaumatoconcha Kornicker and Sohn, 1976a species, T. dandani n. sp. and T. quasiporosa n. sp., have been described in the present paper. Both species have been collected during two expeditions to the Southern Ocean and are found in the deep sea. The first species is most closely related to T. caraionae Kornicker and Sohn, 1976a, but it has a very specific appearance of copulatory organ, anterior part being covered in small spines. The second species is most closely related to T. porosa Kornicker, 1985, and they differ in the carapace shape and morphology, while they have almost identical appearance of the male copulatory organ. A list of Thaumatocyprididae species and a key to the species of Thaumatoconcha are also presented in this paper.

On the genus Thaumatoconcha Kornicker and Sohn (Halocyprida) with description of two new species from Southern Ocean deep sea

Two new Sarsiellinae from Ningaloo Reef, Spinacopia ningalooi sp. nov., and Metasarsiella caleyi sp. nov. are described. Spinacopia ningalooi is the first representative of the genus collected from a coral reef. It differs from the other species by its odd looking posterior infold. Metasarsiella caleyi sp. nov. is the first species of the genus reported from Australia. Keys to species of Spinacopia Kornicker, 1969 and Metasarsiella Kornicker, 1991, and to all the genera of Sarsiellinae are given here, together with an inventory of all the species and information on their distributions and biology. The results of two cladistic analyses (with unweighted and with weighted characters) of the subfamily based on 138 species and 34 morphological characters are presented. The first analysis resulted in seven equally parsimonious trees and the second in just one. The majority rule of the first group of trees and the tree from the second analysis are presented here.

Two new Sarsiellinae (Ostracoda: Myodocopa) from Ningaloo Reef (Western Australia), with a cladistic analysis of the subfamily and keys to genera

Ameiridae Monard, 1927 was previously known from Korea only after one endemic and four cosmopolitan species of the genus Nitokra Boeck, 1865, and a single widely distributed species of the genus Ameira Boeck, 1865, all from brackish enviroments. After a survey of 22 sampling sites and close to 3,500 harpacticoid specimens from various marine enviroments, we report on two new endemic species of Ameira, A. zahaae sp. nov. and A. kimchi sp. nov., from the West Sea and the South Sea respectively. They are both relatively closely related to the previously recorded cosmopolitan A. parvula (Claus, 1866), but show many novel morphological structures in the caudal rami shape and ornamentation. The identity of the cosmopolitan A. parvula in Korea is questioned, and an alternative hypothesis of a species-complex proposed. The fine ornamentation of body somites (especially the pores/sensilla pattern) is studied in detail, and proves to be a very useful new morphological tool in distinguishing closely related spacies in this genus. The genus Pseudameira Sars, 1911 is reported for the first time in Korea, after four females of P. mago sp. nov. from the South Sea. A single damaged female of Proameira cf. simplex (Norman & Scott, 1905) represents the first record of the genus Proameira Lang, 1944 in Korea, Asia, and anywhere in the Pacific. A key to Korean ameirids is also provided, and their apparent rarity in this part of the world noticed.

Three new ameirid harpacticoids from Korea and first record of Proameira simplex (Crustacea: Copepoda: Ameiridae)

The second species of the genus, Macroasteropteron chathamensis sp. nov. is described in the present paper. It was collected from 1000 m depth during the New Zealand national biodiversity programme Ocean Survey 20/20 to the Chatham Rise and the Challenger Plateau. To accommodate this genus, a new subfamily Macroasteropteroninae is described herein. It is defined by the following autapomorphies: locking system on the shell; very small second segment on the second antenna (bearing no dorsal bristles); square shaped third and fourth segments on the same appendage; absence of dorsal bristles on the third segment of the male clasping organ; reverse position of the alpha and beta bristles on the maxillula; almost square shaped skirt on the sixth limb; and a bulbous terminal part of the seventh limb, which, in addition, does not have any bell-bearing bristles. A key to the four subfamilies of Cylindroleberididae is provided.

A new subfamily and species of Ostracoda (Cylindroleberididae, Myodocopa) from the Chatham Rise (New Zealand)

Although exotic species of Ostracoda have been recorded from various sites in Europe, none of them have a widespread European distribution. Reviews of existing literature, examination of specimens, and sampling in Spain and Japan has greatly expanded the known distribution of the candonid ostracode Fabaeformiscandona subacuta (Yang, 1982). We herein present new reports of its presence in mainland eastern Asia. Australia, and South America, and we review its distribution on the Iberian Peninsula. Although this species is globally widespread, we hypothesize that it is an invasive species on the Iberian Peninsula in light of the following facts: it is not known from other European countries, its known global distribution is extremely disjunct, it has not been found during palaeo-limnological investigations of European lakes, and on the Iberian Peninsula it is almost exclusively found in artificial, intensely human-impacted habitats, mostly in reservoirs and ricefields.

GLOBAL DISTRIBUTION OF FABAEFORMISCANDONA SUBACUTA: AN EXOTIC INVASIVE OSTRACODA ON THE IBERIAN PENINSULA?

Candonidae from South Korea are poorly studied, and only nine species have been recorded so far. Here we describe Cypria asiatica sp. nov. and Cryptocandona smithi sp. nov. The first species is the third representative of the genus reported from Korea and it belongs to a group of species of Cypria Zenker, 1854 with reduced swimming setae on the second antenna and without the marginal tubercles on the shell. The group comprises nine species distributed in the Holarctic. Cypria asiatica stands apart from eight other congeneric species by the presence of septa-like structures on the postero-dorsal end of the left valve. Based on the present observations and some previous studies of the subfamily Cyclocypridinae, we here draw attention to the chaetotaxy of the mandibular palp and the chaetotaxy of the fifth limb. The latter shows close similarity between Cyclocypridinae and Paracypridinae and urges further study of homology of setae on this leg between three candonid subfamilies. Cryptocandona smithi is the 14th known Recent species of its genus and the third reported from Korea. It is similar to C. tsukagoshii Smith, 2011 from Japan and C. pygmaea (Ekman, 1908) from Sweden. They all share a peculiar chaetotaxy of the seventh limb and an unusually long posterior seta on the uropodal ramus. The new species can be distinguished from the Swedish species by the morphology of the genital field, and from the Japanese by the shape of the carapace, the length of the f-seta on the seventh limb, and other details of the soft parts. We here report some abnormalities in the morphology of the antennule found in one specimen, and compare this with similar abnormalities reported for C. tsukagoshii and C. brehmi (Klie, 1934), and postulate that this may be a result of the regenerative process of the antennule after damage during development.

TWO NEW CANDONID SPECIES FROM SOUTH KOREA (OSTRACODA, PODOCOPIDA)

Austromesocypris bluffensis sp. n. is described and we report another species, Austromesocypris sp., both collected from subterranean aquatic habitats in Tasmania. This discovery adds a major taxonomic group to the already diverse invertebrate cave fauna of Tasmania, and is of interest because, globally, obligate subterranean aquatic species (stygobites) are poorly represented within the family Cyprididae. The genus Austromesocypris Martens, De Deckker & Rossetti, 2004 is otherwise known to comprise entirely "terrestrial or semi-terrestrial" species. The second species is not described because only juvenile specimens were collected. Both species stand apart from their congeners by the carapace shape, which is rectangular in A. bluffensis and triangular and asymmetrical in the unnamed species. Another unique feature of the new species is the almost symmetrical uropodal rami. We also identify some broader systematic issues within the Scottiinae including the position of two New Zealand species, Scottia audax (Chapman, 1961) and S. insularis Chapman, 1963 in the genus, and point out their closer relationship to the Gondwana genera of Scottiinae, Austromesocypris and Mesocypris Daday, 1910, than to the Palearctic genus Scottia Brady & Norman, 1889, based on the morphology of the maxillula and mandibula. The identity of the Australian records of Scottia audax (Chapman, 1961), Austromesocypris australiensis (De Deckker, 1983) and the Boreal records of Scottia pseudobrowniana Kempf, 1971 are all considered doubtful. A key to the world species of Scottiinae is provided.

Austromesocypris bluffensis sp n. (Crustacea, Ostracoda, Cypridoidea, Scottiinae) from subterranean aquatic habitats in Tasmania, with a key to world species of the subfamily

Invasive species are a global problem, which costs the world economy billions of dollars and world ecosystems millions of tons of herbicides, pesticides and other cides. Anthropogenic translocation of freshwater copepods associated with early shipping activities was postulated for some time, but was never tested with molecular tools. Here, we examine global molecular diversity of one cyclopoid species, test if the current cosmopolitan distribution is a result of anthropogenic translocation or natural dispersal, and investigate a possibility of cryptic speciation. We use patterns of haplotype frequency of DNA and RNA sequences of four genes (12S, 16S, 18S and cytB) and 11 populations (from England, Scotland, France, Germany, USA, New Zealand and Australia) to test inter-and intrapopulation variability, and three different methods (neighbour joining (NJ), maximum likelihood (ML) and maximum parsimony (MP)) for reconstructing their phylogenetic relationships. They were then tested against two competing hypotheses, and complemented by comparative morphology of microcharacters. Reconstructed phylogenies present strong evidence for anthropogenic translocation, with the same haplotype found in highly disjunct populations in Western Australia, Germany and the USA. Four different clades were revealed with the 12S, 16S and cytB genes, probably representing four cryptic species. Morphological examination of females of two clades contributed a set of microcharacters that can be used in the future taxonomic revision of this species complex. We prove for the first time that cuticular pores and sensilla are homologous structures. This research provides evidence for both homogenization of world freshwater fauna and our inadequate methods of identifying some of its most common species.

When anthropogenenic translocation meets cryptic speciation globalized bouillon originates; molecular variability of the cosmopolitan freshwater cyclopoid Macrocyclops albidus (Crustacea: Copepoda)

A previously unsurveyed calcrete aquifer in the Yilgarn region of Western Australia revealed an unprecedented diversity of copepods, representing 67% of that previously recorded in this whole region. Especially diverse was the genus Schizopera, with up to four morphospecies per bore and a significant size difference between them. Aims of this study were to: (1) survey the extent of this diversity using morphological and molecular tools; (2) derive a molecular phylogeny based on COI; and (3) investigate whether high diversity is a result of an explosive radiation, repeated colonisations, or both, size differentiation is a result of parallel evolution or different phylogeny, and whether Schizopera is a recent invasion in inland waters. More than 300 samples were analysed and the COI fragment successfully amplified by PCR from 43 specimens. Seven species and one subspecies are described as new, and three possible cryptic species were detected. Reconstructed phylogenies reveal that both explosive radiation and multiple colonisations are responsible for this richness, and that Schizopera is probably a recent invasion in these habitats. No evidence for parallel evolution was found, interspecific size differentiation being a result of different phylogeny. Sister species have parapatric distributions and show niche partitioning in the area of overlap.

Explosive radiation of the genus Schizopera on a small subterranean island in Western Australia (Copepoda : Harpacticoida): unravelling the cases of cryptic speciation, size differentiation and multiple invasions

Polycopidae Sars, 1866 ostracods from the DIVA II expedition of the RV "Meteor" at the Cape, Angola, and Guinea basins are presented here. They were collected between 26 February and 30 March 2005, from depths between 5,047 and 5,150 m. Metapolycope divae sp. nov. belongs to the subfamily Polycopsisinae Chavtur, 1983, and stands apart from the other representatives of the genus by the morphology of the uropodal lamellae. The remaining eight new species described herein belong to the subfamily Polycopinae Sars, 1866. The genus Archypolycope Chavtur, 1981 is represented in the investigated area by four new species: A. atlantica sp. nov., A. brandtae sp. nov., A. louisi sp. nov., and A. martinezi sp. nov. With the addition of these four new species, this genus is redefined to include six Recent and three fossil species. Archypolycope atlantica is the only representative in the family with six bristles ventrally on the first segment of the mandibula. The other three new species stand apart by the specific shell ornamentation, chaetotaxy of the maxillula, and morphology of the uropodal lamellae. Archypolycope cornea Chavtur, 1981 and A. rotunda Chavtur, 1981, both described from the abyssal depths of the Kuril-Kamchatka trench, are here excluded from the genus. The decision is based on the absence of the peculiar morphology of the fifth limb endopod, which is shared by all other Archypolycope. These species are transferred to the genus Pseudopolycope Chavtur, 1981, because they have a fifth limb endopod consisting of a segment and one terminal bristle, but are placed in separate new subgenus Divacope subgen. nov. The new subgenus differs from the nominotypical subgenus by a much shorter fusion of the two bristles on the Bellonci Organ, and by the presence of hooks on the male antenna. Besides Pseudopolycope (D.) cornea (Chavtur, 1981) comb. nov. and P. (D.) rotunda (Chavtur, 1981) comb. nov, the subgenus has been defined to include one more member: P. (D.) chavturi sp. nov., which is also described from the deep South Atlantic and designated the type species of the new subgenus. It is most closely related to P. (D.) cornea, but differs from it by the chaetotaxy of the antennula and morphology of the exopod mandibula. Two new species, P. (P.) quasivitjazi sp. nov. and P. (P.) spio sp. nov., from the deep South Atlantic are added to the nominotypical subgenus, which now has 15 Recent species. One of the new species described here could not be accommodated into any of the known Polycopinae genera, so the new genus Hyphalocope gen. nov. was erected for it, and defined by the following autapomorphies: completely flat dorsal margin of the shell, presence of the bifurcated bristles on the shell, elongated antennula, and very long Bellonci Organ. Presently, Hyphalocope dorsoithys gen. et sp. nov. is known only from females. We provide a key to genera of the family Polycopidae, and keys to species of the genera Metapolycope, Archypolycope, and Pseudopolycope. In order to learn about the phylogenetic relationships and to point out some current problems of polyphyletic and paraphyletic genera in the subfamily Polycopinae, we perform a cladistic analysis based on 29 morphological characters scored for 91 Recent species. Two species from the genus Metapolycope are chosen as outgroups. Extensive discussion on the distribution and suitability of morphological characters in this family is also provided. All Recent species of Polycopidae are listed at the end, with information about their geographic and bathymetric distributions, habitat, presence of sexes, and body length.

Review and phylogeny of the Recent Polycopidae (Ostracoda, Cladocopina), with descriptions of nine new species, one new genus, and one new subgenus from the deep South Atlantic

Three new freshwater ameirid species were discovered in the Western Australian subterranean habitats and described in this paper. They all proved to belong to the genus Nitocrellopsis Galassi, De Laurentiis & Dole-Olivier, 1999, representing the first record of this genus in Australia. Nitocrellopsis operculata sp. nov. was collected in 2003 in the Pilbara region, during the Pilbara Regional Survey, led by the Western Australian Department of Environment and Conservation (DEC). It can be distinguished from all other congeners by the reduced armature of the antennal exopod, which is an autapomorphic feature. Also, no other species of Nitocrellopsis has cuticular windows on prosomal or urosomal somites, or six elements on the third exopodal segment of the second leg. Nitocrellopsis halsei sp. nov. and N. pinderi sp. nov. are sister-species, collected in 2007 in the neighbouring Yilgarn region, by the private environmental consulting company Bennelongia Pty Ltd. Numerous morphological similarities include somite ornamentation, armature patterns of the swimming legs and the fifth leg, as well as the shape and armature of the antennula, antenna and almost all mouth appendages, while the main differences between the two are observed in the body size and habitus appearance, caudal rami shape and size, presence/absence of large lateral pores on the fourth pedigerous somite, number of spinules on the anal operculum, number of setae on the madibular endopod, and shape of the exopod of the fifth leg. Although they differ from any other congener by a combination of characters, no significant autapomorphic features were observed. In order to find a more natural allocation of these three species, a cladistic analysis is performed on all current members of Nitocrellopsis and three outgroup taxa, based on 45 morphological characters. The resulting cladogram shows that the ingroup is well defined by at least four synapomorphies, but the Australian species from the two regions are only remotely related to each other, showing the importance of looking at small-scale patterns when inferring Gondwanan biogeography. Three sister-species pairs are recognized in the genus and a key to all 12 members is provided.

First record of the harpacticoid genus Nitocrellopsis (Copepoda, Ameiridae) in Australia, with descriptions of three new species

Extensive survey of invertebrates in Korea, led by the National Institute of Biological Resources in Incheon, continues to uncover many new and endemic species, but also elements of neighbouring faunas that were previously unknown here. Hemicyclops tanakai Itoh and Nishida, 2002 was originally described from estuarine mud-flats in Tokyo Bay, Japan. We report one male and two females from a sandy beach on Jeju Island, which represent its first record in Korea and second record ever. No morphological differences were observed between these two disjunct populations, so we expect more records of this species in Korea and Japan. Tisbe ensifer Fischer, 1860 was originally described from Madeira and later on reported from numerous other parts of the Northern Atlantic, as well as from the Indian Ocean. We report two females from a shallow littoral in Sokcho, which represents its first record in Korea and the first record in the entire Pacific Ocean. Because of morphological discrepancies reported in previous records we recognize that this species might be in reality a species complex, and we only tentatively identify our Korean specimens as T. cf. ensifer. We provide numerous light photographs of both species in addition to short descriptions, in hope that they might elucidate global problems of their zoogeography and dispersal of small marine invertebrates in general. Further samplings from Korea and other parts of the world will be necessary to test our identifications and phylogenetic relationships of Korean populations with molecular and other tools.

First records of Hemicyclops tanakai Itoh and Nishida, 2002 and Tisbe ensifer Fischer, 1860 (Crustacea, Copepoda) in Korea

Cylindroleberididae is a peculiar ostracod myodocopid family, characterized by the presence of gills. It accounts for over 200 species described from all bathymetric ranges and from all the world’s oceans. Nevertheless, its biodiversity is still underestimated, with each study brining new taxa to the list. As a result of recent sampling effort in seas around Korea and Japan, we report five cylindroleberid taxa. One of those is described as a new genus (Toyoshioleberis gen. nov.), and four belong to Xenoleberis Kornicker, 1994. Of the latter, three are described as new species, and one has already been reported from Japan, but is the first record for Korea. In fact, our study is also the first record of the family from this country. Having fresh samples provided an opportunity to obtain sequences of three gene markers (16S, 28S, and 18S rRNA), and, by combining those with the ones belonging to Cylindroleberididae available in GenBank, we reconstruct a molecular phylogeny with the aim to assess the position of the new taxa within the family and try to resolve the currently polyphyletic nature of some cylindroleberid taxa. The results of the phylogenetic analyses indicate the monophyly of Xenoleberis and its deep separation from Toyoshioleberis, along with distinct morphological features genetics to support our taxonomic decision. In addition, the phylogenetic results confirm that the general systematic of Cylindroleberididae should be reassessed, in particular the tribes of the subfamily Cyclasteropinae should be given a higher systematic ranking, as suggested previously based on morphology alone.

Phylogenetic position of Xenoleberis Kornicker, 1994 within Cylindroleberidinae (Ostracoda: Myodocopa) with descriptions of three new species and one new genus from the Northwestern Pacific Ocean

The common ostracod genus Echinocythereis has a worldwide and eurybathic distribution, but in Recent sediments, it is more common in cold waters. Its oldest record, dating from the Cretaceous, indicates that the genus should be very useful in stratigraphical and palaeoecological studies, but the taxonomy of Echinocythereis is very complex and includes misinterpretations and misidentifications. Here, we provide an overview of the geographical and stratigraphical distribution of Echinocythereis and clarify the taxonomic status of its type species, Echinocythereis garretti (Howe and McGuirt in Howe et al., 1935) which (contrary to other authors) we consider to be a valid species. Finally, we revise the geographical and stratigraphical distributions and the taxonomy of one 'species complex', which is very common and abundant in the North Atlantic, and has also been recorded from the Pacific and Southern oceans. This species complex has been interpreted as a single species in virtually all publications on North Atlantic ostracods, where Echinocythereis has been identified. The complex includes Echinocythereis echinata (Sars, 1866), Echinocythereis irpex (Brady, 1880) and, the new species described herein, Echinocythereis jorunbrix sp. nov. To aid in subsequent fast and accurate identification of living specimens, we also provide three mitochondrial COI gene fragments of the new species, which represent the first barcodes for the entire Trachyleberididae family. Our study of both shell and soft parts of these three very similar Echinocythereis species indicates that fine details of the shell have a strong phylogenetic signal, but that these can only be properly understood through very careful study of comparative material and with the aid of high magnification microscopy, such as SEM.

Animal Systematics and Evolution Lab

교수님 소개

Ivana Karanovic

연구실 소개

연구실 키워드

알럼나이가 간 회사

연구실 지원 방법

대우 조건

연도별 논문 인용수

저널 & 학회 논문 출판 수

연구실 논문 목록

Genus Hemicytherura (Crustacea, Ostracoda) in Korea with description of a new species and the first insight into its molecular phylogeny

Ostracod shell chemistry as proxy for coastal marine conditions of a highly urbanized megacity (Hong Kong SAR) and an agro-centric oceanic province (Jeju Island, Republic of Korea) - a preliminary comparative analysis

Effects of oxycodone on tonic levels and phasic release of serotonin in the rat nucleus accumbens core

연구실 보유 특허

대학별 입시끈

우리 연구실 모집

교수님 소개

Ivana Karanovic

연구실 키워드

알럼나이가 간 회사

연구실 지원 방법

대우 조건

연도별 논문 인용수

저널 & 학회 논문 출판 수

연구실 논문 목록

Genus Hemicytherura (Crustacea, Ostracoda) in Korea with description of a new species and the first insight into its molecular phylogeny

Ostracod shell chemistry as proxy for coastal marine conditions of a highly urbanized megacity (Hong Kong SAR) and an agro-centric oceanic province (Jeju Island, Republic of Korea) - a preliminary comparative analysis

Effects of oxycodone on tonic levels and phasic release of serotonin in the rat nucleus accumbens core

연구실 보유 특허

최근 3년간 연구실적 높은 연구실

대학별 입시끈

우리 연구실 모집