ABSTRACT
The first insight into the unexpectedly diverse amphipod assemblage of the Durso River (Novorossiysk area) in the SW mountainous pre-Caucasian area is presented. The presence of six species is revealed, including three new records for the area and one species new to science. The phylogenetic relationships of all studied species and their relatives were examined based on the divergence of the COI mtDNA gene marker (barcoding). The conducted research clearly showed that the coastal part of the Black Sea and the adjacent pre-Caucasian river/land areas harbors a significant undescribed diversity, and that the transitional sea/river brackish biotopes are important reservoirs of the endemicity. A new genus, Litorogammarus gen. nov. is proposed for native pebble-dwelling species, namely Echinogammarus karadagiensis Grintsov, 2009, Echinogammarus mazestiensis Marin & Palatov, 2021 and the newly discovered Litorogammarus dursi sp. nov., from the lower (estuarine) part of the Durso River and adjacent coastal areas. These three species form a strongly supported molecular clade and share a number of characters such as smooth body without carinae and setae, antenna II armed with dense curled setae, lacking calceoli, pereopods III-VII with sparse, short setation, epimeral plates armed with spines only, telson lobes longer than broad, gradually tapering, bearing only spines. Pectenogammarus oliviiformis (Greze, 1985) comb. nov. is also discovered in the area and is re-described herein. Although this is probably one of the most abundant and common coastal pebble-dwelling species along the northeastern coasts of the Black Sea, it was previously poorly described and thus overlooked by researchers.
Subject(s)
Amphipoda , Coleoptera , Animals , Amphipoda/genetics , Phylogeny , Rivers , DNA, Mitochondrial/geneticsABSTRACT
The northwestern Pacific soft bottom dwelling spider crab, Pisoides bidentatus (A. Milne-Edwards, 1873) (Brachyura: Majoidea: Epialtidae), is re-described using an integrative approach. As a result, it is transferred to the genus Scyra Dana, 1851 (Epialtidae) based on morphological and molecular data, as well as already described larval morphology, which certainly better reflects the phylogenetic relationships of the species. Japanese Pisoides ortmanni (Balss, 1924), for which morphology and ecology are very similar to P. bidentatus as well as Pugettia quadridens (De Haan, 1839) and the closely related Pugettia ferox Ohtsuchi & Kawamura, 2019, are also transferred to Scyra. The "reduced" morphology of both species is very different from the related northwestern Pacific Scyra spp. and Pugettia spp., which are mostly decorating algae-dwellers. We associate the relatively long ambulatory legs, a smooth tear-drop shaped carapace with a reduced dorsal armature and slightly pronounced pseudorostral spines, characteristic of P. bidentatus and P. ortmanni with their open soft (mainly sand) bottom habitats, where it is difficult to find a foothold or shelter, but it is necessary to resist constant currents. Such morphology is also characteristic of spider crabs of the genera Libinia Leach, 1815 and Doclea Leach, 1815 (Epialtidae: Pisinae), which are also living in similar habitats/conditions and represent a convergent morphological appearance.
Subject(s)
Brachyura , Animals , Japan , Phylogeny , Animal Shells , LarvaABSTRACT
Terrestrial crustaceans are represented by approximately 4,900 species from six main lineages. The diversity of terrestrial taxa ranges from a few genera in Cladocera and Ostracoda to about a third of the known species in Isopoda. Crustaceans are among the smallest as well as the largest terrestrial arthropods. Tiny microcrustaceans (Branchiopoda, Ostracoda, Copepoda) are always associated with water films, while adult stages of macrocrustaceans (Isopoda, Amphipoda, Decapoda) spend most of their lives in terrestrial habitats, being independent of liquid water. Various adaptations in morphology, physiology, reproduction, and behavior allow them to thrive in virtually all geographic areas, including extremely arid habitats. The most derived terrestrial crustaceans have acquired highly developed visual and olfactory systems. The density of soil copepods is sometimes comparable to that of mites and springtails, while the total biomass of decapods on tropical islands can exceed that of mammals in tropical rainforests. During migrations, land crabs create record-breaking aggregations and biomass flows for terrestrial invertebrates. The ecological role of terrestrial microcrustaceans remains poorly studied, while omnivorous macrocrustaceans are important litter transformers and soil bioturbators, occasionally occupying the position of the top predators. Notably, crustaceans are the only group among terrestrial saprotrophic animals widely used by humans as food. Despite the great diversity and ecological impact, terrestrial crustaceans, except for woodlice, are often neglected by terrestrial ecologists. This review aims to narrow this gap discussing the diversity, abundance, adaptations to terrestrial lifestyle, trophic relationships and ecological functions, as well as the main methods used for sampling terrestrial crustaceans.
ABSTRACT
Two new Caucasian species of the genus Niphargus Schidte, 1849 (Crustacea: Amphipoda: Niphargidae), N. rachalechkhumensis sp. nov. and N. tvishiensis sp. nov., are described from the stygobiotic habitats of the Racha-Lechkhumi and Kvemo Svaneti karst systems in Western Georgia. Both newly described species belong to the southwestern Caucasian Niphargus borutzkyi ingroup related to the European carphaticus species complex and can be clearly separated from the congeners by morphological features, mostly in uropod III and epimeral plates, and genetically. Identification key for all known species to the Niphargus borutzkyi ingroup is provided, as well as their phylogenetic relationships, the estimated time of the origin and the current distribution of the ingroup in the Colchis lowland of the southwestern Caucasus are also discussed.
Subject(s)
Amphipoda , Animals , Phylogeny , Georgia (Republic) , EcosystemABSTRACT
A new species of the axiid genus Ambiaxius Sakai de Saint Laurent, 1989 (Decapoda: Axiidae: Axiidea), Ambiaxius abyssalis sp. nov., is described from the Banda Sea, Southwestern Pacific, at a depth of 30003374 m, which represents the first abyssal record of the family Axiidae and even the infraorder Axiidea. The new species shows a combination of morphological features, that places it in an intermediate position between two species groups of the genus, differing in the shape/armature of the rostrum, the length of the article 4 of the antennal peduncle and the morphology of the pleopod I. The genera Ambiaxius Sakai de Saint Laurent, 1989 (the deepest record30003374 m), Calocarides Wollebaek, 1908 (20002036 m) and Anophthalmaxius de Man, 1905 (1788 m) are of the deepest dwelling representatives of the family Axiidae.
Subject(s)
Decapoda , Animal Distribution , Animals , HumansABSTRACT
The Ponto-Caspian region is an endemicity hotspot that harbours several crustacean radiations, among which amphipods are the most diverse. These poorly known species are severely threatened in their native range, while at the same time they are invading European inland waters with significant ecological consequences. A proper taxonomic knowledge of this fauna is paramount for its conservation within the native region and monitoring outside of it. Here, we assemble a DNA barcode reference library for nearly 60% of all known Ponto-Caspian amphipod species. We use several methods to define molecular operational taxonomic units (MOTUs), based on two mitochondrial markers (COI and 16S), and assess their congruence with current species-level taxonomy based on morphology. Depending on the method, we find that 54-69% of species had congruent morpho-molecular boundaries. The cases of incongruence resulted from lumping distinct morphospecies into a single MOTU (7-27%), splitting a morphospecies into several MOTUs (4-28%), or both (4-11%). MOTUs defined by distance-based methods without a priori divergence thresholds showed the highest congruence with morphological taxonomy. These results indicate that DNA barcoding is valuable for clarifying the diversity of Ponto-Caspian amphipods, but reveals that extensive work is needed to resolve taxonomic uncertainties. Our study advances the DNA barcode reference library for the European aquatic biota, paving the way towards improved taxonomic knowledge needed to enhance monitoring and conservation efforts.
Subject(s)
Amphipoda , Butterflies , Amphipoda/genetics , Animals , DNA , DNA Barcoding, Taxonomic/methods , Gene LibraryABSTRACT
Two new mud-dwelling amphipod species of the genus Victoriopisa Karaman Barnard, 1979 (Crustacea: Amphipoda: Eriopisidae) are described from the mangrove habitats of the Cn Gi Mangrove Biosphere Reserve and the estuary of the Be River, Vietnam. Both species are characterized by an anteroventral margin of the head being entire, the presence of eyes, the absence of deep excavation on propodus (palm) and well-marked excavation on dactylus of gnathopod 2, relatively long and slender distal segment of uropod 3. The combination of these features clearly separate the newly discovered species from Victoriopisa ovata (Dang Le, 2005) described from Hi Phng, North Vietnam, and other congeneric species. Victoriopisa nhatrangensis sp. nov. from the mouth of the B River (Nha Trang) can be clearly separated from Victoriopisa cangio sp. nov. from the Cn Gi Mangrove Biosphere Reserve by the absence of a tuft of setae on the distodorsal margin of article 2 of antenna 1, not anteriorly expanded distoventral margin of propodus (palm) of gnathopod 2, different shape and armature epimeral plates and telson, proportion and armature of uropods 23. The article also discusses the previous records of the genus Victoriopisa from the coastal waters of Vietnam, and as the result Victoriopisa chilkensis (Chilton, 1921) and Eriopisa elongata (Bruzelius, 1859) are excluded from the fauna of Vietnam.
Subject(s)
Amphipoda , Animals , Ecosystem , Estuaries , Rivers , VietnamABSTRACT
A new species of mud dwelling burrowing shrimp Wolffogebia cangioensis sp. nov. is described from the Soài Rap River delta in the Can Gio Mangrove Biosphere Reserve, South Vietnam. The presence of Wolffogebia inermis Sakai, 1982 in the same area is also confirmed based on the freshly collected male specimen. Thorough morphological descriptions, genetic data (barcoding) and in situ ecological observations are presented for both species. A review of the previous records from Vietnam and Southeastern Asia as well as the taxonomic status of the genus Wolffogebia Sakai, 1982 within the family Upogebiidae are also discussed in the article. The key to all species of the genus is presented.
Subject(s)
Crustacea , Decapoda , Animals , Male , Animal Distribution , VietnamABSTRACT
Four new species of the Palaearctic crangonyctid amphipod genus Lyurella Derzhavin, 1939 (Crustacea: Amphipoda: Crangonyctidae), L. mikhailovi sp. n., L. fanagorica sp. n., L. fontinalis sp. n. and L. asheensis sp. n., are described based on an integrative approach from the subterranean habitats of the southwestern foothills of the Greater Caucasian Ridge (the north-eastern Black Sea coast). Despite the relative proximity of the habitats, the interspecific genetic divergence (by COI mtDNA gene marker) between the newly outlined Caucasian species of the genus varied from 11 to 21%, demonstrating a long-term isolation and lack of gene flow for at least 37Mya, starting from the Pliocene. The lowest genetic divergence between L. shepsiensis Sidorov, 2015 and L. asheensis sp. n., estimated as 4%, is also considered species-specific due to the presence of distinct morphological differences. We discuss the phylogeny, morphology, and distribution and provide a key for all known species of Lyurella. DNA barcoding data for all species, including the type species of the genus, Lyurella hyrcana Derzhavin, 1939, are presented for the first time.
Subject(s)
Amphipoda , Amphipoda/genetics , Animals , Ecosystem , Phylogeny , Russia , Species SpecificityABSTRACT
The article presents a brief review on the fauna of the axiidean and gebiidean burrowing mud shrimps and their external parasites in the northeastern coast of the Black Sea, where only two rather common species, Gilvossius candidus (Olivi, 1792) and Upogebia pusilla (Petagna, 1792) (Gebiidea: Upogebiidae), were previously recorded. Necallianassa truncata (Giard Bonnier, 1890) is confirmed and Gilvossius tyrrhenus (Petagna, 1792) (Axiidea: Callianassidae) is firstly recorded for the shallow waters of the northeastern Black Sea, where it was previously probably confused with common and widely distributed Gilvossius candidus (Olivi, 1792). Color photographs of the four species, enhancing the recognition of those species in fields, are provided.
Subject(s)
Decapoda , Parasites , Animals , Black Sea , CrustaceaABSTRACT
A new species of the genus Niphargus is described from the Gelendzhik-Tuapse area of the Russian southwestern Caucasus. It belongs to the "puteanus" species group and phylogenetically related to Caucasian N. ciscaucasicus and N. talikadzei, separating from other Caucasian species of the genus by the presence of 2 hooks in retinacules on pleopods, different rami of uropod I both in males and females, and relatively large inner ramus of uropod III. Molecular study has revealed that Niphargus bzhidik sp. nov. and related N. ciscaucasicus are relicts of the Late Miocene speciation, associated with the Messinian crisis (5.96-5.33Mya) separated widespread Paratethys species, which survived in long-term genetic isolation for a long time. The new species is blind and epigean, and probably unable to spread over long distances, but this way of life probably allowed surviving in refugee during the Quaternary period with a colder climate. Analysis of stable isotopes (δ13C/δ15N) revealed that the new species is carnivorous, in contrast to another studied stygobiotic herbivorous Niphargus species (e.g., Niphargus cf. tauricus). The key to the Caucasian and Eastern Asian species of the genus Niphargus, known from the territory of the former USSR, is presented in the article. [http://zoobank.org/urn:lsid:zoobank.org:act:E0019189-2432-4B64-B153-94C43FDD93E3].
Subject(s)
Amphipoda , Amphipoda/anatomy & histology , Amphipoda/classification , Amphipoda/genetics , Animals , Female , Male , Russia , Species SpecificityABSTRACT
The sublittoral hermit crab Pagurus trigonocheirus (Stimpson, 1858) (Crustacea: Decapoda: Paguridae) is recorded from depths of 80-200 m along the continental coastline of the Peter the Great Bay, Sea of Japan. The exact sampling localities as well as photographs of live specimens are presented in the paper. Doubtful records of hermit crabs from the southern Russian coastline of the Sea of Japan are also discussed.
Subject(s)
Anomura , Animals , Bays , Japan , Specimen HandlingABSTRACT
A new stygobiotic atyid shrimp from the genus Xiphocaridinella Sadowsky, 1930 (Crustacea: Decapoda: Atyidae) is described based on morphology and DNA analysis from an underground lake inside the Motena Cave (Martvili Municipality, Samegrelo-Zemo Svaneti, Western Georgia, Caucasus). The new species is genetically well isolated from the West Georgian relatives and clearly differs from the other Caucasian congeners by specific lanceolate unarmed rostrum, turned forward, and by long fingers of pereiopod I and II in both males and females.
Subject(s)
Decapoda , Animals , Caves , Female , Georgia (Republic) , MaleABSTRACT
The precopulatory mate guarding (amplexus) was observed in epigean Niphargus cf. magnus Birstein, 1940 collected near Tuapse in the Western Caucasus of Russia. The records of amplexing representatives of the subterranean genus Niphargus Schiödte, 1849 (Crustacea: Amphipoda: Niphargidae) are extremely rare, and there are no publications describing the amplexus in this amphipod genus. The presented report shows that Niphargus have a chemically stimulated short-time amplexus immediately after the molt of the female, similar to the representatives of relative epigean and subterranean gammaridean amphipods. It is relatively short in time, possibly, because of adaptation to inhabit narrows spaces in underground habitats.
Subject(s)
Amphipoda , Animals , Ecosystem , Female , RussiaABSTRACT
A new species of the aberrant monotypic genus Planotergum Balss, 1935 (Brachyura: Majidae: Planoterginae) is described from the southern part of the Red Sea, based on a single female recently found in the collection of the Zoological Museum of Moscow State University. The new species is clearly distinguished from Planotergum mirabile Balss, 1935 in the form of carapace, antennal article and third maxilliped, as well as morphology of the ambulatory legs. The record extends the known range of Planotergum, previously known only from the eastern Indian Ocean and Western Pacific, by more than 7000 km.
ABSTRACT
A new cancrid crab species Glebocarcinus kashini sp. nov. (Decapoda: Brachyura: Cancridae) is described from Russian coastal waters of the Sea of Japan. The new species can be clearly separated from relative and sibling, Glebocarcinus amphioetus (Rathbun, 1898), by a less prominent and granulated dorsal surface of the carapace and dorsal surface of the cheliped propodus, less prominent sculpture of the carapace front and bluntly triangular anterolateral teeth of the carapace. Comparison of COI gene sequences supports the subdivision of these two species and shows their clear genetic separation from a related species, the American pygmy rock crab, G. oregonensis (Dana, 1852). Along the mainland coast of the Sea of Japan, G. kashini and G. amphioetus possibly overlap only in Posyet Bay and adjacent areas; the new species is distributed to the north from the bay while G. amphioetus is distributed to the south. Previous and new records of G. amphioetus from the area are discussed.
Subject(s)
Brachyura , Decapoda , Animal Distribution , Animals , DNA , Japan , RussiaABSTRACT
One of the most northern representatives of the family Atyidae, an amphidromous shrimp Paratya borealis Volk, 1938 (Crustacea: Decapoda: Atyidae), is considered as a junior synonym of Paratya compressa (De Haan, 1844 [in De Haan, 1833-1850]) based on morphological and genetic investigations of the specimens collected in rivers flowing into Peter the Great Bay and Posyeta Bay along the Russian coasts of the Sea of Japan. The study greatly increases the area of distribution of P. compressa to north for more than 1000 km and suggests that the species probably inhabit rivers flowing into the Sea of Japan also along North and South Korean coasts.
Subject(s)
Decapoda , Rivers , Animals , Asia, Eastern , Japan , RussiaABSTRACT
DNA barcoding of stygobiotic shrimps of the genus Xiphocaridinella Sadowsky, 1930 (Crustacea: Decapoda: Atyidae) collected in underground streams flowing inside two neighboring large karst caves (Otap and Abrskil Ñaves) revealed the presence of two distinct genetic lineages representing the first case of species co-occurrence in the Western Caucasus. The paper presents the complete morphological re-description of stygobiotic atyid shrimp Xiphocaridinella ablaskiri (Birstein, 1939) and the description of a new species using genetic and morphological analysis. Other known cases of co-occurrence of several stygobiotic shrimp species in the same cave system as well as new genetic data (COI mtDNA) on Western Caucasian species of the genus Xiphocaridinella are discussed in the paper.
Subject(s)
Caves , Decapoda , Animals , DNA, MitochondrialABSTRACT
Two new species of amphipod genus Stenothoe Dana, 1852 (Crustacea, Amphipoda, Stenothoidae) are described from hydroids collected in fouling communities of floating aquaculture platforms in Nhatrang Bay (Vietnam) representing the first record of the genus from coastal waters of Vietnam. The new species can be clearly separated from congeners by the structure of the mandible, maxilla II, the shape of gnathopod II, the armature of uropod III and the telson. The discussion is presented in the paper.
Subject(s)
Amphipoda , Animals , Aquaculture , Bays , VietnamABSTRACT
OBJECTIVE: This study examined adherence to alert-based cues for plantar pressure offloading in patients with diabetic foot disease. METHOD AND DESIGN: Participants (n = 17) with in diabetic foot remission (history of neuropathic ulceration) were instructed to wear a smart insole system (the SurroSense Rx, Orpyx Medical Technologies Inc, Calgary, Canada) over a three-month period. This device is designed to cue offloading to manage unprotected sustained plantar pressures in an effort to prevent foot ulceration. A successful response to an alert was defined as pressure offloading, which occurred within 20 minutes of the alert onset. Patient adherence, defined as daily hours of device wear, was determined using sensor data and patient questionnaires. Changes in these parameters were assessed monthly. RESULTS: Patients demonstrating increased adherence over the course of the study received more alerts (0.82 ± 0.31 alerts/hour) than patients whose adherence did not improve (0.36 ± 0.46 alerts/hour, P = .156). By the final stages of the study, participants who had received at least one alert every two hours were more adherent with offloading than participants who received fewer alerts (52.5 ± 4.1% vs 24.7 ± 22.4%, P = .043). Furthermore, duration of time from alert generation to successful offloading was significantly greater in the group receiving fewer alerts. This was measured in the third month with an effect size Cohen's d = 1.739, P = .043. CONCLUSION: The results suggest a minimum number of alerts (one every two hours) is required for patients with diabetic neuropathy to optimally respond to offloading cues from a smart insole system.