Komai Tomoyuki

Natural History Museum and Institute, Chiba · Animal Sciences Division

The deep-sea shrimp genus Nematocarcinus A. Milne-Edwards, 1881 is known for its challenging species identification due to fragility of specimens and subtle morphological differences. While diagnostic characteristics for species discrimination have been improved, the identification of certain species, particularly in the Indo-West Pacific region, r...

Faunal collections made during the Thai-Danish BIOSHELF surveys in the Andaman Sea off southwestern Thailand contain six species of the deep-water caridean shrimp genus Glyphocrangon A. Milne-Edwards,

In the present study, a new species of the alpheid shrimp genus Potamalpheops Powell, 1979, Potamalpheops yamakawai, is described from Japan. The new species, representing the first species of the genus to be recorded from the Japanese waters, appears to be close to P. miyai Yeo & Ng, 1997, known from mangroves in Indonesia and the Philippines, amo...

Two new species of the axiid shrimp genus Eiconaxius Bate, 1888, are described from seamounts in the Nishi-Shichito Ridge, northwestern Pacific off Japan, during recent cruises of R/V Kaimei of the Japan Agency for Marine-Earth Science and Technology, exploring the marine protected area (MPA). Eiconaxius latirostrum sp. nov. is described on the bas...

A new species of the pagurid hermit crab genus Catapagurus A. Milne-Edwards, 1880, is described based on a single male specimen from off Okinawa Islands, Ryukyu Islands, southwestern Japan, at a depth of 150 m. Catapagurus cracens sp. nov. appears closest to C. tenuilamina Komai, Miller & Malay, 2022 among the 27 congeners, but is distinguished fro...

A new species of the thorid shrimp genus Lebbeus White, 1847, is described and illustrated on the basis of two specimens collected from the recently discovered Amami Rift hot vent field in the Ryukyu region in southwestern Japan, at a depth of 628 m. Lebbeus parvirostris sp. nov. is morphologically similar to L. microceros (Krøyer, 1841), L. mundus...

During a survey of the shallow water decapod fauna in the Miura Peninsula, Kanagawa Prefecture, central Japan, four specimens of a new palaemonid shrimp, Palaemon parvibrachium n. sp., were collected from sea grass beds of Nanozostera japonica (Ascherson & Graebner) Tomlinson & Posluszny, 2001. The new species appears morphologically similar to P....

The callichirid ghost shrimp genus Glypturus Stimpson, 1866 was represented until now by four extant species worldwide. Only G. armatus A. Milne-Edwards, 1870 is known from the western Pacific. In this study, we describe G. ferox n. sp. based on seven specimens collected from the Ryukyu Islands, southwestern Japan. All specimens of the new species...

The sponge associated axiid shrimp Eiconaxius farreae Ortmann, 1891 was originally described based on specimens from Sagami Bay, central Japan. Morphological examination of many specimens of Eiconaxius collected from Sagami Bay and nearby areas, and genetic data from the mitochondrial COI and 16S rRNA genes have revealed that three species are repr...

The Shiretoko Peninsula, located at the southernmost point of the Sea of Okhotsk, was registered as a World Natural Heritage in 2005 in recognition of its rich biodiversity and an example of the interaction between marine and terrestrial ecosystems. However, there is insufficient information on its marine biota, which is an essential component of t...

A new species of alvinocaridid shrimp is reported, from the Northwest Eifuku hydrothermal vent field at 1619–1667 m depth on the Mariana Arc. A comprehensive phylogenetic reconstruction of Alvinocarididae based on the mitochondrial cytochrome c oxidase subunit I (COI) gene including this new species reveals the paraphyly of the genus Rimicaris Will...

Metacrimenes fenestra, a new palaemonid genus and species is described on the basis of an ovigerous female and one juvenile specimen from Suruga Bay, central Japan. The specimens were associated with the stalked crinoid Metacrinus rotundus Carpenter, 1885, collected at a depth of 131-200 m. Photographs taken in situ indicate that the shrimp lives e...

Two species of munidid squat lobsters are newly reported from the North-West Pacific off Japan based on material collected by the recent cruise of R/V Kaimei (KM20-10C cruise) of the Japan Agency for Marine-Earth Science and Technology, exploring seamounts in the marine protected area (MPA): Gonionida kaimei n. sp. and Trapezionida psylla (Macphers...

A new species of the thorid shrimp genus Heptacarpus Holmes, 1900, H. sadoi, is described and illustrated on the basis of six specimens from the southeastern coast of the Boso Peninsula, central Japan. All the specimens were collected from intertidal tide pools at low tide. Heptacarpus sadoi n. sp. belongs to the species group with epipods on the p...

Examination of material from Japanese waters has disclosed that two species have been confounded under Tymolus uncifer (Ortmann, 1892) (Decapoda: Brachyura: Cyclodorippidae) in previous literature. The identity of Tymolus uncifer sensu stricto is clarified in reference to the lectotype, and the second taxon is herein attributed to T. melanommus (Do...

Examination of the material collected by Taiwan deep-sea cruises reveals the presence of five species of the deep-sea shrimp genus Glyphocrangon A. Milne-Edwards, 1881, representing new records for Taiwan and Dongsha (Pratas Island; under jurisdiction of Taiwan). These species are Glyphocrangon albatrossae , G. caecescens , G. indonesiensis , G. ma...

The callichirid ghost shrimp Grynaminna tamakii Poore, 2000 was heretofore known only by the original description. The type series consisted of specimens from the south of Shimabara Peninsula, Nagasaki Prefecture, although it was noted that the species occurred also at Hayasaki Inlet on Oyano Island, Kami-Amakusa, Kumamoto Prefecture. In this study...

The availability of many topotypic specimens of the deepsea shrimp Glyphocrangon stenolepis Chace, 1984 (Caridea: Glyphocrangonidae) recently collected off of Pratas Island (Dongsha), northern South China Sea, enabled us to establish the true identity of this species. Material previously identified as Glyphocrangon stenolepis from Taiwan and Japan...

A small collection of chirostyloid squat lobsters was studied, collected from seamounts on the Nishi-Shichito, West Mariana, and Central Mariana ridges, which have been collectively designated as marine protected areas (MPAs) of Japan. Specimens were collected using a remotely operated vehicle (ROV). Four species belonging to three families were id...

A new species of the alpheid shrimp genus Athanas Leach, 1814 is described based on a holotype from Wakasa Bay, Sea of Japan side of Honshu, Japan, at a depth of 90 m. Athanas exilis n. sp. appears close to A. sydnyensis Anker & Ahyong, 2007, but is distinguished from the latter by some morphological features, including the different shape of the t...

A new species of the laomediid mud shrimp genus Naushonia Kingsley, 1897 is described and illustrated based on seven specimens collected from Okinawa Island, Ryukyu Islands, southwestern Japan. All specimens of Naushonia karashimai n. sp. were collected from burrows of a large axiidean shrimp, Neaxius acanthus (A. Milne-Edwards, 1879), which inhabi...

The alpheid shrimp genus Metabetaeus Borradaile, 1899 was previously known from two species associated with anchialine pools and caves, M. minutus (Whitelegge, 1897) and M. lohena Banner & Banner, 1960, and one species inhabiting in coral reef, M. mcphersonae Anker, 2010. In this study, a new species of the genus is described based on fourteen spec...

A new palaemonid species, Periclimenes variabilis, is described and illustrated on the basis of four specimens from the Ritto Seamount, West Marina Ridge, northwestern Pacific, at depths of 642-666 m. Specimens of the new species were collected with an unidentified hexacoral of Primnoidae (Cnidaria), an antipatharian octocoral Leiopathes sp. (Cnida...

A new species of the alpheid shrimp genus Salmoneus Holthuis, 1955 is described based on two specimens from the Seto Inland Sea, Japan. Salmoneus aduncus n. sp. is strikingly similar to S. rostratus Barnard, 1962, which is distributed widely in the tropical Indo-West Pacific, but the new species is distinguished from the latter by the proportionall...

The ghost shrimp genus Callianassa Leach, 1814 is currently represented by six taxa, of which five are known from the eastern Atlantic and only C. persica Sakai, 2005 from the Persian Gulf. In this study, a new species of Callianassa is described and illustrated on the basis of material from the subtidal soft sediments (at 26–28 m depth) in Wakasa...

The diogenid hermit crab genus Pseudopaguristes McLaughlin, 2002 is currently represented by 15 species worldwide. In this study, we describe a new species of the genus, P. flavioculus, based on a unique male holotype from off Sarigan, Northern Mariana Islands, Micronesia, at depth of 131–133 m. The new species appears similar to the type species o...

Comparison between materials from various localities in the North Pacific and North Atlantic, including specimens identified with Lebbeus polaris (Sabine, 1824) in previous studies, led the authors to reinstate “Hippolyte St. Pauli” Brandt, 1851 as a valid species of the thorid genus Lebbeus White, 1847 (Decapoda: Caridea), removed from the synonym...

A new species of the deep-sea caridean genus Glyphocrangon A. Milne-Edwards, 1880, G. obtusis n.sp., is described and illustrated on the basis of the material collected in the South China Sea off the Pratas Island. It appears close to G. hakuhoae Takeda & Hanamura, 1994 and G. robusta Komai, 2004 among the 93 described species in Glyphocrangon. Fro...

Based on a collection of deep-water caridean shrimps captured by commercial baited traps and gill nets operated in Nemuro Strait, southwestern part of the Sea of Okhotsk, three new species of the thorid shrimp genus Lebbeus White, 1847, L. rufomaculosus n. sp., L. subtilis n. sp. and L. tenuipes n. sp., are described and illustrated. Integrative ap...

The deep-sea caridean shrimp Bathypalaemonella pandaloides (Rathbun, 1906) (Bathypalaemonellidae) was heretofore known only from Hawaii (type locality) and French Polynesia. In this article, we report this rarely collected species on the basis of a single male specimen from the Ritto Seamount on the West Mariana Ridge, northwestern Pacific, at a de...

A new species of the alpheid shrimp genus Richalpheus Anker & Jeng, 2006 is described on the basis of 10 specimens collected from three locations in Kagoshima Prefecture, Kyushu, Japan. Richalpheus laeuadigitus n. sp. appears close to R. palmeri Anker & Jeng, 2006 and R. dahabensis Anker & Dworschak, 2007 among the three known congeners, but differ...

The poorly known pinnotherid crab, Pinnixa haematosticta Sakai, 1934, is redescribed on the basis of female holotype and additional specimens, including males and females, from Japan. The male characters of the species are documented for the first time. The species is transferred to Indopinnixa Manning & Morton, 1987 because the male pleonal somite...

We describe three new species of hermit crab of the pagurid genera, Catapagurus A. Milne-Edwards, 1880, Nematopagurus A. Milne-Edwards & Bouvier, 1892 and Pagurixus Melin, 1939, on the basis of material collected during the scientific cruise to the Northern Mariana Islands conducted by the U.S. National Oceanographic and Atmospheric Administration...

We report the first occurrence record of the freshwater ectoparasitic platyhelminth Scutariella japonica (Matjašič, 1990) from Hokkaido, Japan. The flatworms were collected from the surface of exoskeleton and the inside of branchial chamber of the atyid shrimp Neocaridina sp. aff. davidi. Phylogenetic analysis based on the 18S + 28S concatenated da...

The Mariana Islands consist of two volcanic island arc chains, one volcanically inactive frontal arc in the Southern Marianas and a younger, volcanically active arc in the Northern Marianas. Given their extreme remoteness, the hermit crab fauna of the uninhabited northern islands are little-known. In this study we collected and examined hermit crab...

A new species of the processid shrimp genus Nikoides Paul’son, 1875, N. subdistalis, is described and illustrated on the basis of five specimens collected from Kushimoto, Wakayama Prefecture, Japan, at depths of 7–12 m. The new species appears most similar to N. maldivensis Borradaile, 1915 among the 10 known congeners, but is notable in the unique...

Examination of material from various Japanese localities clarified that the estuarine crab Ptychognathus glaber Stimpson, 1858 is possibly restricted to the Ogasawara Islands, Japan. Specimens from the Ryukyu Islands, thought to represent P. glaber, actually represent P. lipkei N.K. Ng, 2010 instead, previously known only from Cebu, the Philippines...

A small collection of pagurid hermit crabs, collected from coral reefs and marine caves on Christmas and Cocos (Keeling) Islands, Indian Ocean Territory of Australia, was studied. The following 11 species, including three new to science, were identified: At Christmas Island, where the major part of the collection was done, seven of the eight specie...

Lebbeus compressus Holthuis, 1947, one of the five peculiar "crested species" of the thorid shrimp genus Lebbeus White, 1847, has been considered to be endemic to Japan. This species inhabits deep waters but has an attractive coloration. Examination of four specimens from northeastern Taiwan, which are morphologically similar to L. compressus, led...

Three new species of the pagurid hermit crab genus Catapagurus A. Milne-Edwards, 1880 are described and illustrated on the basis of material from the Bohol Sea, Philippines, collected by the PANGLAO 2004 Marine Biodiversity Project. Catapagurus exilidigitus new species, appears closest to C. tanimbarensis McLaughlin, 1997 within the C. misakiensis...

A new species of the chirostylid squat lobster genus Uroptychodes Baba, 2004, U. fuscilineatus, is described and illustrated on the basis of a single ovigerous female from the Uraga Channel, central Japan, at depth of 250 m. The new species appears most similar to U. spinimarginatus (Henderson, 1885) and U. yapensis Dong, Gan & Li, 2021 among the 1...

A new alpheid shrimp species, provisionally assigned to the genus Salmoneus Holthuis, 1955, is described and illustrated on the basis of three specimens extracted from intertidal soft sediments on seagrass beds at Iriomote Island, southern Ryukyu Islands, Japan. Salmoneus singularis n. sp. is highly distinctive within the genus in having a pair of...

Two species of the upogebiida mud shrimp genus Gebiacantha Ngoc-Ho, 1989, currently represented by 19 described species, are reported from the Ryukyu Islands, Japan. The first, G. acanthochela (Sakai, 1967), is redescribed in detail based on two female specimens from Amami Islands the second discovered since the original description, enabling bette...

Two species of axiid shrimp are reported from sublittoral to upper bathyal waters around the Ogasawara Islands, Japan. The first, Bouvieraxius keiensis Sakai, 1992, is recorded from Japanese waters for the first time, although it is known widely from the southwestern Pacific to western Indian Ocean. Taxonomic problems of this taxon are pointed out....

Manaxius paullus, a new species of axiid burrowing shrimp, is described on the basis of a female holotype from the Society Islands, French Polynesia, and a female paratype from the Ryukyu Islands, Japan. Both specimens were collected on shallow coral reefs. The new species is morphologically closest to five of 17 congeners, viz., M. euophthalmus (d...

A new pagurid hermit crab species is assigned to the genus Kumepagurus Komai & Osawa, 2012, previously represented only by the type species, K. cavernicolus Komai & Osawa, 2012, known only from a marine cave on Ryukyu Islands, northwestern Pacific. The assignment is made because of the lack of an accessory tooth on the maxilliped 3 ischium, the ope...

The laomediid mud shrimp genus Axianassa Schmitt, 1924 is currently represented by 12 species worldwide. In this study, a new species of the genus, A. microlepis, is described and illustrated on the basis of two female specimens obtained from Awaji Island, eastern part of the Seto Inland Sea, Japan, at depth of 8 m. The type specimens were collecte...

A new species of the pagurid hermit crab genus Turleania McLaughlin, 1997, T. rubriguttatus, is described on the basis of two specimens, including one male and one female, from shallow subtidal waters in Kochi Prefecture, Japan. The new species appears close to T. albatrossae (McLaughlin & Haig, 1996), known from the Philippines, but the proximally...

The pinnotherid crab, Pinnothera obesa Dana, 1852, was originally described on the basis of material from Fiji, but its taxonomic status has long been obscure because the original description and figures are too brief and schematic by modern standards and the types are also lost. Examination of newly collected material from Fiji revealed the presen...

A new species of the alpheid shrimp genus Automate de Man, 1888, A. awaji, is described on the basis of an ovigerous female holotype and three paratype specimens (sex not determined) from Awaji Island, Hyogo Prefecture, Japan. The specimens were collected from soft sediments on a shallow subtidal flat (depth 4-8 m) using an airlift suction sampler....

A collection of the caridean shrimp genus Glyphocrangon A. Milne-Edwards, 1881 (Glyphocrangonidae), made during the South Java Deep-Sea Biodiversity Expedition 2018 (SJADES 2018) comprises of six species, including one new to science: G. hakuhoae Takeda & Hanamura, 1994, G. indonesiensis Komai, 2004b, G. juxtaculeata Chace, 1984, G. proxima Komai,...

A new species of the laomediid mud shrimp genus Naushonia Kingsley, 1897, N. kiiensis, is described and illustrated on the basis of a single male specimen from Kii Peninsula, central Japan, at a sublittoral depth of 14 m. The new species is morphologically closest to N. serratipalma Komai & Anker, 2010, known from French Polynesia and the Red Sea c...

Three species of the crangonid shrimp genus Metacrangon Zarenkov, 1965 (Decapoda: Caridea), are reported from the south of Java, Indonesia, on the basis of material collected by the South Java Deep-Sea Biodiversity Expedition 2018 (SJADES 2018): M. clevai Komai, 2012, M. punctata Komai, 2012, and a new species, M. latirostris. No species of the gen...

A poorly known callianassid ghost shrimp species, Scallasis amboinae Bate, 1888, is redescribed and illustrated on the basis of the holotype and new material from Papua New Guinea. A new species, S. inermis, is described from the Ryukyu Islands, Japan. Callianassa (Cheramus) pygmaea De Man 1928 is synonymised with S. amboinae. All seven species of...

Two species of the mud shrimp genus Upogebia Leach, 1814 (Gebiidea: Upogebiidae) are recorded from India for the first time based on material from Tamil Nadu: U. hexaceras (Ortmann, 1894) and U. nithyanandan (Sakai, Türkay & Al Aidaroos, 2015). Both were found in burrows in an unidentified sponge. Upogebia nithyanandan is resurrected as a valid spe...

The occurrence of a little known upogebiid mud shrimp, Upogebia pugnax de Man, 1905, in Japanese waters is confirmed on the basis of five specimens from Iriomote Island, southern Ryukyu Islands. The species has been recorded with certainty only from Indonesia and New Caledonia. Upogebia pugnax is morphologically very similar to U. sakaii Ngoc-Ho, 1...

A new species of diogenid hermit crab, Diogenes minimus, is described and illustrated on the basis of material from shallow subtidal waters (5-19 m) in central Japan. It appears close to D. holthuisi Asakura & Tachikawa, 2010, but easily distinguished from the latter by the shape of the antennal acicle, non-elongate male left cheliped and the armat...

A new species of the caridean genus Alvinocaris , A. marimonte sp. nov., is described and illustrated on the basis of specimens collected from hydrothermal vents at three locations in Izu-Bonin and Mariana Arcs of the north-western Pacific Ocean, Myojin Knoll (1224 m depth), NW Eifuku (1574–1582 m depth) and NW Rota seamounts (525 m depth). It is t...

The morphology of the zoeal stages IX and XI of the shrimp Thalassocaris lucida is described and illustrated in detail from plankton specimens identified by barcoding of the mitochondrial 16S ribosomal RNA gene (sequence similarities 99.4–99.6%). The present study confirms the larval morphology of Thalassocaris , that shows distinct features within...

A new species of the laomediid mud shrimp genus Axianassa Schmitt, 1924, A. planioculus, is described and illustrated on the basis of a single male specimen from intertidal muddy sand flat of Kabira Bay, Ishigaki Island, southern Ryukyu Islands, Japan. Axianassa planioculus n. sp. is morphologically closest to A. mineri Boone, 1931, known from Paci...

A new caridean shrimp family, Chlorotocellidae, is established to accommodate four genera previously assigned to Pandalidae, viz., Chlorotocella Balss, 1914 (type genus), Chlorocurtis Kemp, 1925, Anachlorocurtis Hayashi, 1975, and Miropandalus Bruce, 1983, which represents the sister clade to a clade consisting of all other pandalid genera (includi...

A new species of the alvinocaridid shrimp genus Rimicaris Williams & Rona, 1986, R. falkorae n. sp., is described and illustrated based on material from deep-sea hydrothermal vents (3,630–3,912 m deep) on the Mariana Back Arc Spreading Centre, northwestern Pacific, representing the tenth described species of the genus. The new species is morphologi...

Two individuals of "monster larvae" belonging to the genus Cerataspis (Decapoda: Penaeoidea: Aristeidae) were collected in the western North Pacific in 2016. The smaller one (carapace length 7.3 mm) was collected by daytime plankton net operation towed at a shallow layer (25 m to the surface), and the larger one (carapace length 11.5 mm) was collec...

A new genus of the family Callianassidae, Laticallichirus, is established for "Neocallichirus" grandis Karasawa & Goda, 1996, a ghost shrimp species heretofore represented only by fossil materials from the middle to upper Pleistocene of Japan. The newly collected specimens came from two Japanese localities: Numazu, Shizuoka Prefecture (Suruga Bay)...

A new species of the squat lobster genus Eumunida Smith, 1883 (Chirostyloidea: Eumunididae), E. multispina, is described and illustrated primarily on the basis of two male specimens from the Arabian Sea off the Kerala State, southwestern India, at depths of 250-400 m. One specimen from Lakshadweep, previously identified with E. funambulus Gordon, 1...

The Decapoda is one of the largest orders within the class Malacostraca, comprising approximately 14,000 extant species and including many commercially important species. For biodiversity monitoring in a non-invasive manner, a new set of PCR primers was developed for metabarcoding environmental DNA (eDNA) from decapod crustaceans. The new primers (...

The palaemonid shrimp genus Palaemon Weber 1795 is currently represented by 87 species worldwide, of which 36 species inhabit freshwater environments. In this study, we describe a new species of the genus, P. septemtrionalis, primarily based on material collected from rivers in Miyagi Prefecture, Tohoku District, northeastern Japan. The present new...

A new species of the thorid genus Lebbeus White, 1847, L. java new species, is described on the basis of two ovigerous female specimens from south of Java, Indonesia, collected at depths of 637-689 m. It is morphologically most similar to L. formosus Chang, Komai & Chan, 2010, known from off Taiwan, amongst about 70 congeners, but subtle morphologi...

A little known littoral hermit crab, Clibanarius clibanarius (Herbst, 1791), is redescribed on the basis of material from southern India, supplemented by the photographs of the type material. The species appears closest to C. infraspinatus Hilgendorf, 1869, but the absence of a prominent ventral spine or protuberance on the cheliped meri immediatel...

A poorly known leucosiid crab, Pseudophilyra punctulata Chen & Ng, 2003, originally described on the basis of an immature male holotype and an immature female paratype from Singapore, is rediscovered and rediagnosed on the basis of material from Thailand, the Philippines and the Ryukyu Islands (Japan). In addition, a new species closely related to...

The present study deals with a collection of deep-sea shrimp of the pandalid genus Pandalopsis Spence Bate, 1888 from the Nemuro Strait, Hokkaido, southwestern part of the Sea of Okhotsk. Three new species are described and illustrated: Pandalopsis capillus n. sp., P. houyuu n. sp. and P. princeps n. sp. In addition, Pandalopsis glabra Kobjakova, 1...

Mirograpsus asper is described as a new genus and new species in the subfamily Ilyograpsinae Števčić, 2005, of the family Macrophthalmidae Dana, 1851, on the basis of a single male specimen from Ishigaki Island, Ryukyu Islands, Japan. The new genus most closely resembles the monotypic Apograpsus Komai & Wada, 2008 (type species, Ilyograpsus paan-tu...

Two species of the callianassid ghost shrimp genus Neocallichirus Sakai, 1988 are newly recorded from Iran. Neocallichirus darvishi n. sp. appears close to N. jousseaumei (Nobili, 1904), but combined morphological and genetic analyses provide evidence for recognition of the new taxon. Neocallichirus manningi Kazmi & Kazmi, 1992, originally describe...

A new species of the hermit crab genus Diogenes Dana, 1851, D. spongicola, is described and illustrated on the basis of material collected from two locations off southern India. It appears close to D. takedai Rahayu, 2012 among about 70 congeners, but easily differentiated from the latter by the spinulose anterolateral margins of the shield, the ar...

A new species of hermit crab, Pagurus fraserorum n. sp. (family Paguridae) is described from rocky subtidal reefs off KwaZulu-Natal, South Africa, and illustrated using both conventional drawings and colour photographs, and via three-dimensional (3D) X-ray micro-computed tomography (μCT). Because of the limitation μCT has in detecting very fine and...

Pagurus_fraserorum rotation movie male holotype right cheliped. Pagurus fraserorum n. sp. 3D reconstruction of right cheliped of male holotype, isosurface rendering. (MP4)

Pagurus fraserorum rotation movie female paratype. Pagurus fraserorum n. sp. 3D reconstruction of female paratype, wrapped and scanned in parafilm; scanning artefacts and ‘noise’ not removed, leaving majority of setation, parts of the pleon and the eggs carried on the pleopods. (MP4)

Pagurus_fraserorum rotation movie male holotype left cheliped. 3D reconstruction of left cheliped of male holotype, isosurface rendering. (MP4)

Six species of caridean shrimps from four families are recorded from Japanese waters for the first time on the basis of material from the Ryukyu Islands and its adjacent waters, collected during research cruises of the T/RV “Toyoshio-maru” of Faculty of Applied Biological Science, Hiroshima University: two species of Crangonidae, Lissosabinea unisp...

A new species of the snapping shrimp genus Alpheus Fabricius, 1798, A. longipalma, is described and illustrated on the basis of material from Kagoshima Bay, Kyushu, Japan. It is referred to the A. brevirostris (Olivier, 1811) species group, and appears closest to A. macroskeles Alcock & Anderson, 1894, known with certainty from the Bay of Bengal an...

For 130 years the diogenid genus Paguropsis Henderson, 1888 was considered monotypic for an unusual species, P.typica Henderson, 1888, described from the Philippines and seldom reported since. Although scantly studied, this species is known to live in striking symbiosis with a colonial sea anemone that the hermit can stretch back and forth like a b...

Two new species of the crangonid shrimp genus Metacrangon Zarenkov, 1965, are described and illustrated on the basis of materials collected from the Okinawa Trough, Ryukyu Islands, southern Japan, during diving operations of remotely operated vehicles (ROVs): M. ryukyu n. sp. from off Iheya Island, at depth of 986 m; and Metacrangon kaiko n. sp. fr...

Examination of samples collected from the Ryukyu Islands, Japan, has revealed the common occurrence of the callianassid ghost shrimp Lepidophthalmus tridentatus (von Martens, 1868), although literature records of the species are rather scarce. The specimens examined in this study were collected from Amami-ohshima Island, the Okinawa Islands and the...

A new species of alpheid shrimp, Thuylamea shiranui, is described and illustrated on the basis of five specimens from Yatsushiro Sea, western Kyushu, Japan. It is closely related to T. camelus Nguyên, 2001, the type species of the heretofore monotypic genus Thuylamea Nguyên, 2001, known from South China, Vietnam and Singapore. The complete lack of...

Two species of alpheid shrimp collected from a marine cave off Ie Island, Okinawa Islands, Ryukyu Islands, Japan, are reported. Caligoneus cavernicola n. gen., n. sp., is described on the basis of six specimens, including two ovigerous individuals. The new monotypic genus shares a number of features with Salmoneus Holthuis, 1955 and Triacanthoneus...

The majoid genus Goniopugettia Sakai, 1986, was established to include a new species Goniopugettia tanakae Sakai, 1986, as well as Pugettia sagamiensis Gordon, 1930. Although Goniopugettia tanakae Sakai, 1986, was subsequently designated as the type species of the genus by Ng et al. (2008), the identity of this species has been shrouded in uncertai...

Munida michaeli, a new species of deep-sea squat lobster (Munididae), is described and illustrated on the basis of a single male specimen collected off Okinawa Island, Ryukyu Islands, Japan, at depths of 641-650 m. It closely resembles M. sacksi Macpherson, 1993 known with certainty only from the Philippines, but different spination of the carapace...

Munida michaeli, a new species of deep-sea squat lobster (Munididae), is described and illustrated on the basis of a single male specimen collected off Okinawa Island, Ryukyu Islands, Japan, at depths of 641-650 m. It closely resembles M. sacksi Macpherson, 1993 known with certainty only from the Philippines, but different spination of the carapace...

Two deep-sea caridean shrimps are reported on the basis of topotypic materials recently collected from the Andaman Sea off Myanmar, eastern Indian Ocean: Pasiphaea unispinosa Wood-Mason, 1892 (Pasiphaeidae) and Glyphocrangon smithii Wood-Mason & Alcock, 1891b (Glyphocrangonidae). These two taxa are poorly known in literature, and thus their diagnos...

A new species of the rare caridean genus Bresilia Calman, 1896, B. cinctus, is described and illustrated on the basis of a single ovigerous female specimen collected from Sagami Bay, central Japan, at 218–318 m depth. The new species is morphologically most similar to B. rufioculus Komai & Yamada, 2011, known only from shallow water cave of Ie Isla...