New Aoridae (Crustacea: Amphipoda) from Tasmanian kelp holdfasts

Three new aorid amphipod species from Tasmanian kelp holdfasts are described: Microdeutopus varietensis sp. nov., Lembos clematis sp. nov. and L. verrucularum sp. nov. Strong sub-ocular regression of the head is a usual feature of the genus Microdeutopus and is shown by M. varietensis. It is not, however, typical of the other known Australian/NewZealand Microdeutopus species (M. haswelli and M. apopo). The Tasmanian Lembos species (L. chiltoni, L. clematis and L. verrucularum) are not known from New Zealand, where the genus is represented by L. pertinax, L. acherontis and L. hippocrenes. The Tasmanian Lembos species display the condition of the mandibular palp that typifies the genus, that is, article 3 longer than article 2 (cf. the New Zealand species which display the reverse, unusual, condition).     

Three new species of Gammarus from Shaanxi,China (Crustacea: Amphipoda: Gammaridae)

Three new species, Gammarus shenmuensis n. sp., G. murarius n. sp. and G. martensi n. sp. are described, based on the collections from the Shaanxi Province of China. The morphological characters that distinguish these different species are presented. Distribution data on these gammarids are also given.     

Two new species of Niphargus (Crustacea: Amphipoda) from Iran

Two Niphargus species, Niphargus khayyami sp. nov. and Niphargus khwarizmi sp. nov., are morphologically analysed and described. Both species are found in western Iran, which represents the easternmost border of the distributional area for this subterranean amphipod genus. We were unable to attribute N. khayyami sp. nov. to any of 80 Niphargus species that were analysed for 28S ribosomal DNA sequences; sequencing of N. khwarizmi sp. nov. failed. Niphargid findings from west Asia recorded in 5 years imply that almost one half of the range of this large freshwater amphipod genus is still unexplored. http://www.zoobank.org/urn:lsid:zoobank.org:pub:9E9E7CC9-83E2-419F-A394-57197305E1EF     

Biting mechanism of the amphipod Anonyx (Crustacea: Amphipoda: Lysianassoidea)

Anonyx amphipods feed extensively on dead or weakened animals, often of large size. They cut off strips of food using the wide incisor processes of their mandibles like a pair of shears. The mandibles and associated mouthparts are specialized for this shearing action. The strips of food are coiled and packed into their proventriculi.     

A new landhopper species of Myanmarorchestia (Crustacea: Amphipoda: Talitridae) from Yunnan,China

A new landhopper talitrid, Myanmarorchestia nunomurai Nakano and Morino, sp. nov., from Yunnan Province, China is described. Since species of Myanmarorchestia were known only from Mt. Victoria of the Arakan Mountains of Myanmar, this is the first record of the genus from China. Myanmarorchestia nunomurai is characterised by its coxal gills on gnathopod 2 to pereopod 6 without filamentous projections while the other congeners from Myanmar possess some/all of the coxal gills with filamentous projections. Additionally, M. nunomurai can be diagnosed by the sexually dimorphic uropod 2, of which the outer ramus bears a robust seta on the midlateral surface and a few rows of small teeth on the middle to distodorsal surface.

http://zoobank.org/urn:lsid:zoobank.org:pub:3C014FFC-F4D6-4F18-8188-33672367ABB1     

Two new phoxocephalids (Crustacea: Amphipoda: Phoxocephalidae) from the south-west Atlantic

A new genus and species, Parafoxiphalus longicarpus, and a new species, Metharpinia protuberantis belonging to the family Phoxocephalidae, are described from the Argentine Sea. Both taxa were collected from sandy substrata in the intertidal and subtidal regions. Parafoxiphalus longicarpus is related to Foxiphalus Barnard, 1979 and they share many characters, most of them in plesiomorphic condition. Metharpinia protuberantis is an intermediate species between Metharpinia Schellenberg, 1931 and Microphoxus Barnard, 1960, and its assignation to the first genus is discussed.     

Zoogeography and evolutionary ecology of the genus Platorchestia (Crustacea,Amphipoda, Talitridae)

ABSTRACT

Species of the genus Platorchestia occur both in the northern hemisphere (18 species) and southern hemisphere (three species plus a synanthropically introduced species in South America and South Africa). The greater number of endemic Platorchestia species in the North Pacific Ocean suggests that it could be the epicentre of evolution for this genus. North-western Pacific Platorchestia includes 15 species which occupy five ecotopes: wrack (seven species), terrestrial leaf litter (five species), freshwater (one species), marsh (one species) and tentatively present in caves (one species). North-eastern Pacific Platorchestia includes only one putative driftwood specialist, with no other species found in North American coastal habitats. This compares with three good endemic Platorchestia species (plus two putative additional species) and only two ecotopes: wrack (three species) and freshwater (two species) from the North Atlantic Ocean, inclusive of the Gulf of Mexico and Mediterranean Sea. Insufficient data is available to consider Platorchestia zoogeography for the Arabian Sea and Bay of Bengal. Synanthropic dispersal involving Platorchestia in Polynesian outrigger canoes, or in solid ballast carried in the holds of wooden sailing ships has been identified as a potential complicating factor in the zoogeography of this genus. Platorchestia is proposed to have arisen on Laurasia and is therefore basically a northern hemisphere genus. Questions concerning Platorchestia zoogeography and evolutionary ecology are posed and two methods (more intensive field sampling and molecular genetics) are suggested to be the way to solve them.     

Morphology of a calceolus,an antennal receptor of gammaridean Amphipoda (Crustacea)

The internal structure of calceoli, in the gammaridean amphipod, Eusirus perdentatus Chevreux, has been examined for the first time using fast atom etching in conjunction with scanning electron microscopy. The etching technique was used to remove surface layers of the calceolus, revealing a complex array of cuticular fibres supporting the proximal cup and distal plates. The cup was found to consist of a radial set of about 200 rod-like subunits. The results add weight to the view that calceoli may function as phonoreceptors, sensitive to water borne pressure waves.     

A taxonomic study on the Phtisicidae (Crustacea: Amphipoda) of New South Wales,Australia

The present study reviews the taxonomy of the Phtisicidae (Crustacea: Amphipoda) from the coast of New South Wales, Australia. The following seven species are described; Dodecas decacentrum Stebbing, 1910b, Dodecas hexacentrum Mayer, 1903, Hircella cornigera (Haswell, 1879b), Metaproto novaehollandiae (Haswell, 1879a), Notoprotomima smithi gen. nov., sp. nov., Paraproto sp. and Perotripus sp. Generic diagnoses of Notoprotomima gen. nov., Dodecas, Hircella and Metaproto are provided based on the present materials. Notoprotomima smithi is fully described as a new species of the new genus. Dodecas decacentrum differs from Dodecas hexacentrum by the presence of paired dorsodistal projections on pereonite 2, paired mid-dorsal projections on pereonites 3 and 4 and shorter gill length on pereonites 2 and 3. Hircella cornigera and Metaproto novaehollandiae are described in detail. The larger mature males of M. novaehollandiae possess the unusual massive type of the propodus of gnathopod 2. The extended distribution of Perotripus to the New South Wales coast is noted. A key for these phtisicid amphipods from New South Wales, Australia is provided.     

A new genus and species of Caprellidae (Crustacea: Amphipoda) from Kiribati

ABSTRACT

Luisacaprella eliae gen. nov, sp. nov. (Crustacea, Amphipoda, Caprellidae) is described bwct ased on specimens collected from Kiribati, Pacific Ocean. The new genus is close to Aciconula but can be mainly distinguished by the following characteristics: (1) pereonites 6 and 7 are fused in Luisacaprella gen. nov. while they are separated in Aciconula; (2) the setal formula of mandibular palp is 2-x-1 in Luisacaprella and 1-x-1 in Aciconula; (3) pereopods 3 and 4 are two-articulate in males and females of Luisacaprella, whereas there is sexual dimorphism in Aciconula, and males have pereopods 3 and 4 two-articulate while females have pereopod 3 two- or three-articulate and pereopod 4 four-articulate. The new species L. eliae is additionally characterised by its tiny size (<3 mm). The new taxon was collected from dead branching coral of shallow waters (3–32 m). Further studies targeting small caprellids which could easily be overlooked from substrates such as sediments and dead corals are needed to properly understand the global caprellid diversity of tropical and temperate areas.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:1F5A24BE-A7AC-4D3C-A087-F7284F84A2DC     

Ultrastructure of the pereopodal dactyls in the family Phronimidae Dana, 1852 (Crustacea: Amphipoda: Hyperiidea)

Species of the Phronimidae were studied for the micromorphology of their pereopods. Novel structures were found on the dactyls and are described in detail. A hypothesis is advanced that these structures serve also for external digestion and absorption of the tissues of their gelatinous plankton hosts.