Richer De Forges Research Articles

A new species and new record of Samadinia Ng & Richer de Forges, 2013 (Crustacea: Brachyura: Epaltidae) from deepwater off north-eastern Queensland, Australia

A new species of Samadinia Richer de Forges & Ng, 2013, is described from deep-water off northeastern Queensland, Australia. Samadinia hela n. sp. is distinctive in having pseudorostral spines longer than the maximum carapace length, slender preorbital spines that are curved inwards over the base of the rostrum, and long and laterally flattened hepatic and lateral bracnchial spine plates. A new record of S. despereaux (Lee, Richer de Forges & Ng, 2019) from Queensland is also reported in this study.

The taxonomy of spider crabs of the genera Eurynome, Choniognathus, Seiitaiodes and Kasagia (Crustacea: Brachyura: Majidae) from southwest Indian Ocean.

The taxonomy of majid spider crabs collected from recent southwest Indian Ocean cruises belonging to Eurynome Leach, 1814, and allied genera is treated. Eurynome longimana Stimpson, 1857, long synonymised with the European E. aspera (Pennant, 1777), is here recognised as a distinct species. Stimpsons (1857) species can be distinguished by the armature of granules on the third maxilliped, proportions and armature of the ambulatory merus, relatively shorter ambulatory dactylus, structure of the male sternopleonal cavity and relative proportions of the male first gonopod. The composition of Choniognathus Rathbun, 1932, is discussed and the type species, C. koreensis Rathbun, 1932, is figured. One species, C. verhoeffi (Balss, 1929), is not considered to be a member of Choniognathus and its taxonomy is discussed. A new spinose species, C. spinosus, is also described. Seiitaoides Griffin Tranter, 1986, is revised, and two new species, S. mirabilis and S. kabuto, are described and compared with S. orientalis (Sakai, 1961) and S. stimpsoni (Miers, 1884). The poorly known Eurynome elegans Stebbing, 1921 is rediscovered, its taxonomy clarified and the species is shown to belong to Kasagia Richer de Forges Ng, 2007. A second species of Kasagia, K. sudhakari Padate, Manjebrayakath Ng, 2019, recently described from the Arabian Sea is recorded from southwest Indian Ocean.

Rare deep-water crabs (Crustacea: Decapoda) from Indian waters, with description of one new species

Deep-water brachyuran crabs collected from the Indian Exclusive Economic Zone by the Fishery Oceanographic Research Vessel “Sagar Sampada” in the southeastern Arabian Sea (50 m depth), southwestern Bay of Bengal (307 m depth), and in the vicinity of the Andaman and Nicobar Archipelagos (271-535 m depth) were studied. They are referred to Sphaerodromia kendalli (Alcock and Anderson, 1894) and Sphaerodromia nux Alcock, 1900 (family Dromiidae), Intesius brevipes sp. nov. (family Mathildellidae), Tunepugettia corbariae B.Y. Lee, Richer de Forges and P.K.L. Ng, 2019 (family Epialtidae), Cyrtomaia suhmii Miers, 1885 (family Inachidae), Chaceon alcocki Ghosh and Manning, 1993 (family Geryonidae), and Sphenomerides trapezioides (Wood-Mason, 1891) (family Trapeziidae). Sphaerodromia nux and T. corbariae are new records from Indian waters. The first male specimen of C. alcocki is reported, with a description of the male first gonopod. Intesius brevipes sp. nov. is the fifth species of the genus, differing from the four known congeners in the form and setation of the carapace, distinctly curved and granular anterolateral margins, and shorter pereopods with much slender merus and carpus articles.

Description of a new species of deep-sea spider crab from the genus Crocydocinus Lee, Richer de Forges & Ng, 2019, from the south-eastern Arabian Sea (Crustacea: Decapoda: Majoidea: Epialtidae)

A new species of spider crab is described from two male specimens collected from the southeastern Arabian Sea. This species differs from its congeners in the absence of uograstric granule on carapace, the presence of two granules along lateral margin of carapace at branchial region, the presence of granules on P2-P4 dactyli and the constricted distal tip of the male first gonopod.

New records of two spider crabs (Decapoda, Brachyura, Majidae) from Korea

Abstract Two species of the family Majidae, Sakaija japonica (Rathbun, 1932) and Schizophroida simodaensis Sakai, 1933, are herein newly reported from Korean waters. These are also the first records of Sakaija Ng & Richer de Forges, 2015 and Schizophroida Griffin & Tranter, 1986 in Korea. There are currently 14 majoid species from nine genera in Korea. Herein, diagnoses of Sakaija japonica and Schizophroida simodaensis are provided together with illustrations.

More limbs on the tree: mitogenome characterisation and systematic position of ‘living fossil’ species Neoglyphea inopinata and Laurentaeglyphea neocaledonica (Decapoda : Glypheidea : Glypheidae)

Glypheids first appeared in the Lower Triassic period and were believed to be extinct until specimens of Neoglyphea inopinata Forest & Saint Laurent and Laurentaeglyphea neocaledonica Richer de Forges were described in 1975 and 2006, respectively. The finding of extant species has meant that molecular data can now be used to complement morphological and fossil-based studies to investigate the relationships of Glypheidea within the Decapoda. However, despite several molecular studies, the placement of this infraorder within the decapod phylogenetic tree is not resolved. One limitation is that molecular resources available for glypheids have been limited to a few nuclear and mitochondrial gene fragments. Many of the more recent large-scale studies of decapod phylogeny have used information from complete mitogenomes, but have excluded the infraorder Glypheidea due to the unavailability of complete mitogenome sequences. Using next-generation sequencing, we successfully sequenced and assembled complete mitogenome sequences from museum specimens of N. inopinata and L. neocaledonica, the only two extant species of glypheids. With these sequences, we constructed the first decapod phylogenetic tree based on whole mitogenome sequences that includes Glypheidea as one of 10 decapod infraorders positioned within the suborder Pleocyemata. From this, the Glypheidea appears to be a relatively derived lineage related to the Polychelida and Astacidea. Also in our study, we conducted a survey on currently available decapod mitogenome resources available on National Center for Biotechnology Information (NCBI) and identified infraorders that would benefit from more strategic and expanded taxonomic sampling.

Deep-sea spider crabs of the families Epialtidae MacLeay, 1838 and Inachidae MacLeay, 1838, from the South China Sea, with descriptions of two new species (Decapoda, Brachyura, Majoidea)

Recent expeditions (NANHAI 2014, DONGSHA 2014 and ZHONGSHA 2015) conducted in deep waters of the South China Sea obtained interesting material of various spider crabs (Majoidea) including several new records for the area, and two new species of epialtids of the genera Oxypleurodon Miers, 1885 and Stegopleurodon Richer de Forges & Ng, 2009. Two poorly known species, previously only known from their types, Rochinia strangeri Serène & Lohavanijaya, 1973 and R. kagoshimensis (Rathbun, 1932) comb. nov., are redescribed, refigured, and their taxonomy discussed.

The species of Mathildella Guinot and Richer de Forges, 1981 and Neopilumnoplax Serène in Guinot, 1969 (Decapoda: Brachyura: Mathildellidae)

The mathildellid crab genus Neopilumnoplax Serene in Guinot, 1969 was originally proposed for several deep-sea species previously placed in Pilumnoplax Stimpson, 1858, including P. sinclairi Alcock and Anderson, 1899 from the Bay of Bengal. Further revision led to creation of Mathildella Guinot and Richer de Forges, 1981, which differed chiefly from Neopilumnoplax in having one instead of two pairs of endostomial ridges, and in the width of the anterior abdominal somites. Most species of both genera are relatively well known, but N. sinclairi , until now, was known with certainty only from the type description and figure of the female holotype housed in the collections of the Zoological Survey of India. Examination of the holotype of Pilumnoplax sinclairi , facilitated by the late Michael Turkay, revealed P. sinclairi to belong to Mathildella instead of Neopilumnoplax . Moreover, comparison of M. sinclairi with M. kyushupalauensis Takeda and Watabe, 2004 from Komahashi Seamount off Japan revealed that the two nominal species may well be synonyms. We defer synonymising the two species, however, until male M. sinclairi can be studied. We also clarify selected historical records of “ Pilumnoplax ” species from Indonesia and mainland Japan, from which we confirm the occurrence of Mathildella serrata (Sakai, 1974) and M. kyushupalauensis , respectively. In addition, we recognise an additional character separating Neopilumnoplax from Mathildella in the respective presence or absence of epibranchial ridges on the carapace. Neopilumnoplax michalis sp. nov. from the Southwest Indian Ocean Ridge is described and compared with its nearest congener, N. heterochir (Studer, 1883) from off southern Africa. The identity of Pseudorhombilia ( Pilumnoplax ) normani Miers in Tizzard, Moseley, Buchanan and Murray, 1885 from Nightingale Island (Tristan da Cunha) and Agulhas Bank, off South Africa, is fixed by lectotype designation as a junior synonym of N. heterochir .

Reappraisal of species attributed to Halicarcinus White, 1846 (Crustacea: Decapoda: Brachyura: Hymenosomatidae) with diagnosis of four new genera and one new species from New Ireland, Papua New Guinea.

Species of Hymenosomatidae previously treated as species or junior synonyms of species of Halicarcinus White, 1846 are assigned to this and other genera. Halicarcinus is restricted to seven valid species; Rhynchoplax Stimpson, 1858, since 1980 synonymised with Halicarcinus, is now recognised with four species; four species are added to Micas Ng & Richer de Forges, 1996 (making five in total); and four new genera are erected: Culexisoma n. gen. (two species, one newly described), Lucascinus n. gen. (three species), Nasutoplax n. gen. (one species) and Stimpsoplax n. gen. (three species). The genera are distinguished primarily on features of the gonopod 1, interaction of the pleon with the thoracic sternal pleonal cavity, maxilliped 3, male cheliped, propodus-dactylus articulation of the ambulatory pereopods, and degree of fusion of the pleomeres. Species of Halicarcinus s.s. share a short trilobed rostrum, strongly curved gonopod 1 and free pleomeres. Some members of other genera may have a similar rostrum but typically have a long median projection with or without lateral angles or spines variously developed at the anterior margin of a supraocular eave. A lectotype of Hymenicus cookii Filhol, 1885 (now Halicarcinus cookii) is designated. A lectotype of Hymenosoma leachii Guérin, 1832, in Guérin-Méneville 1829-1837 (synonym of Halicarcinus planatus Fabricius, 1775) is selected in the interests of nomenclatural stability. Halicarcinus quoyi (H. Milne Edwards, 1853) is recognised as a senior synonym of the more widely used H. innominatus Richardson, 1949, which is itself a nomen nudum because it was erected without type designation. We also recognise Hymenicus marmoratus Chilton, 1882, as a junior synonym of Halicarcinus varius (Dana, 1851). Species of Rhynchoplax share a curved gonopod 1, falcate dactyli on pereopods 2-5 and fused pleomeres 3-4 in males and 3-5 in females. Species of Micas have a twisted gonopod 1 with the apex bent and only one or two subapical teeth on the dactylus of ambulatory legs. Culexisoma n. gen. is established for Halicarcinus ginowan Naruse & Komai, 2009, and a second species, Culexisoma niugini n. sp., from Papua New Guinea as type species. The genus is unique among these genera in having the male pleon not tightly engaging with the thoracic sternum, maxillipeds 3 not fully covering the buccal cavern and in having a strongly sexually dimorphic rostrum. Species of Lucascinus n. gen. share a male cheliped with 'nut-cracker'-like fingers and free pleomeres in both male and female. Nasutoplax n. gen. differs from others in the erect lateral profile of the rostrum and in gonopod 1 with an unusual subterminal spinulose projection on its posterior face. Stimpsoplax n. gen. has a gonopod 1 with a swollen base and a narrow strongly twisted distal part, tapering distally to a curved apex. Each genus is diagnosed, all species are tabulated, some discussed in more detail, and generic diagnostic characters are illustrated.

The species of Moloha Barnard, 1946, from the western Indian Ocean, with the description of a new species from India (Crustacea: Brachyura: Homolidae)

The taxonomy of the deep-water homolid crabs Moloha grandperrini Guinot & Richer de Forges, 1995 and M. alisae Guinot & Richer de Forges, 1995 is re-examined, and the types redescribed and figured. Moloha alisae is reported from South Africa for the first time. A new species with an inflated carapace, M. tumida sp. nov., is also described from southern India and compared with its closest congeners.

Leucosiid crabs (Crustacea: Decapoda: Brachyura) from Taiwan, with three new records.

Four leucosiid species from Taiwan are presented. Ebalia nudipes Sakai, 1963, with its male first gonopod figured for the first time. Galilia petricola Komai & Tsuchida, 2014, is recorded on the basis of a larger specimen, and distinguishing features with its only congener, G. narusei Ng & Richer de Forges, 2007, reappraised. Nursia rhomboidalis (Miers, 1879), previously known only from Japan, Korea, and mainland China, is also recorded from Taiwan. Myra fugax (Fabricius, 1798) is now formally recorded from Taiwan, and female characters identified to help separate the three known Taiwanese species of Myra.

Leucosiid crabs from Papua New Guinea, with descriptions of eight new species (Crustacea: Decapoda: Brachyura).

Twenty-five species of leucosiid crabs are reported from Madang Province, Papua New Guinea. Of these, seven are new to science: two each are included in Alox Tan & Ng, 1995 and Tanaoa Galil, 2003, and one each in Ryphila Galil, 2009, Seulocia Galil, 2005, and Urnalana Galil, 2005. Fifteen additional species are new records for Papua New Guinea: Alox rugosum (Stimpson, 1858), Ancylodactyla nana (Zarenkov, 1990), Arcania heptacantha De Man, 1907, Heterolithadia fallax (Henderson, 1893), Hiplyra longimana (A. Milne Edwards, 1874), Myra curtimana Galil, 2001, M. digitata Galil 2004, Nursilia dentata Bell, 1855, Oreotlos etor Tan & Richer de Forges, 1993, Parilia major Sakai, 1961, Raylilia coniculifera Galil, 2001, R. uenoi (Takeda, 1995), Toru pilus (Tan, 1996), Urashima pustuloides (Sakai, 1961) and Leucosia rubripalma Galil, 2003. The new species are described and illustrated, and their affinities with allied taxa discussed. Colour photographs are provided for 20 species.

New morphological and distributional information on Homolodromiidae and Homolidae (Decapoda: Brachyura) from the Americas, with description of a new species and comments on western Pacific species

Seventeen crab species of Homolodromiidae and Homolidae, in seven genera, are recognized in the Atlantic and Pacific coasts of the Americas. The genus Dicranodromia A. Milne-Edwards, 1880, is recorded for the first time from the eastern Pacific with a new species described from the Galapagos Islands. Nine species, five Homolodromiidae and four Homolidae, are taxonomically evaluated and circumscribed based on morphological information, their geographic and bathymetric distribution clarified and updated, and the similarities and differences of each with other members of the families discussed. Photographs, SEM photomicrographs and line drawings for selected species, including notes on habitat, nomenclature, and distinguishing features, are provided. Biramous uropods and complete pleopod formula in males are discovered to occur in juveniles of Homola minima Guinot and Richer de Forges, 1995, providing evidence that homoloidian and eubrachyuran pleonal locking-system (homoloidian and the eubrachyuran sockets) are not homologous. A checklist of all homolodromiid and homolid species known from both ocean sides of the Americas, with their bathymetric ranges, is presented. The diagnostic characters of one western Pacific species, Lamoha williamsi (Takeda, 1980), are reevaluated.

Deep-Sea decapod crustaceans (Caridea, Polychelida, Anomura and Brachyura) collected from the Nikko Seamounts, Mariana Arc, using a remotely operated vehicle "Hyper-Dolphin".

Samples and images of deep-water benthic decapod crustaceans were collected from the Nikko Seamounts, Mariana Arc, at depths of 520-680 m, by using the remotely operate vehicle "Hyper-Dolphin", equipped with a high definition camera, digital camera, manipulators and slurp gun (suction sampler). The following seven species were collected, of which three are new to science: Plesionika unicolor n. sp. (Caridea: Pandalidae), Homeryon armarium Galil, 2000 (Polychelida: Polychelidae), Eumunida nikko n. sp. (Anomura: Eumunididae), Michelopagurus limatulus (Henderson, 1888) (Anomura: Paguridae), Galilia petricola n. sp. (Brachyura: Leucosiidae), Cyrtomaia micronesica Richer de Forges & Ng, 2007 (Brachyura: Inachidae), and Progeryon mus Ng & Guinot, 1999 (Brachyura: Progeryonidae). Affinities of these three new species are discussed. All but H. armarium are recorded from the Japanese Exclusive Economic Zone for the first time. Brief notes on ecology and/or behavior are given for each species.

Odiomarinae nov. subfam., a new subfamily for two primitive genera of Hymenosomatidae MacLeay, 1838, with preliminary remarks on the family (Crustacea, Decapoda, Brachyura)

A new subfamily Odiomarinae nov. subfam. is erected to receive two primitive genera of the eubrachyuran family Hymenosomatidae MacLeay, 1838: Odiomaris Ng & Richer de Forges, 1996, and Amarinus Lucas, 1980, mostly from fresh and estuarine waters of the Indo-West Pacific region. The new subfamily is characterised by the presence of “intercalated platelets” on the male abdomen, either articulated and moveable or relatively less well demarcated. The hymenosomatid platelets are actually vestigial uropods that are similar to those, also showing as dorsal plates, of the podotreme Dynomenidae Ortmann, 1892, and Dromiidae De Haan, 1833. The hymenosomatid uropod differs from the podotreme ones by the deep socket that is excavated at its ventral side and thus corresponds to the typical eubrachyuran press-button system. The odiomarine socket is particularly interesting because it provides morphological and phylogenetic criteria for identifying podotreme uropods and eubrachyuran sockets as homologues. In addition to several other plesiomorphic characters, the retention of dorsal uropods in the Hymenosomatidae, a unique known case in the Eubrachyura Saint Laurent, 1980, and evidence of an ancient lineage, allows re-defining and preliminarily interpreting the exclusive combination of characters of the family and to reconsider its status within the Eubrachyura.

New records of deep-sea spider crabs of the genus Cyrtomaia Miers, 1886, from the Pacific Ocean, with description of a new species (Crustacea: Decapoda: Brachyura: Majidae)

Recent collections of deep-sea majid crabs from the South Pacific Ocean and Taiwan provide new records of five species of Cyrtomaia Miers, 1886, and a new species from French Polynesia, C. polynesica n. sp. The news species is most similar to the recently described C. micronesica Richer de Forges & Ng, 2007, but differs from this species in the morphology of its carapace and pereopods.

Rhadinoplax, a new genus of Progeryonidae Stevcic, 2005, for Carcinoplax microphthalmus Guinot & Richer de Forges, 1981, and a redescription of Paragalene longicrura (Nardo, 1868) (Crustacea: Decapoda: Brachyura: Goneplacoidea)

Rhadinoplax, new genus, is described for Carcinoplax microphthalmus Guinot & Richer de Forges, 1981, a species previously included in the family Goneplacidae MacLeay, 1838. The new genus is transferred to the family Progeryonidae Števčić, 2005, superfamily Goneplacoidea. The poorly known progeryonid, Paragalene Kossmann, 1878, is also redescribed and figured.

A new species of Cyrtomaia Miers, 1886 (Crustacea: Decapoda: Brachyura: Majidae) from Micronesia

A new species of deep-sea spider crab of the genus Cyrtomaia (Brachyura: Majidae) is described from Guam and Palau. Cyrtomaia micronesica n. sp. is differentiated from its closest congener, C. cornuta Guinot & Richer de Forges, 1988, from New Caledonia by a different carapace armature, shorter basal antennal spines, proportionately longer chelipeds, relatively longer male second and fourth ambulatory meri, and a different male first pleopod.

Laurentaeglyphea, un nouveau genre pour la seconde espèce actuelle de Glyphéide récemment découverte (Crustacea Décapoda Glypheidae)

In 1975, a recent member of a large group of Crustacea Decapoda was described as Neoglyphea inopinata Forest & de Saint Laurent, until now only known as fossils and presumed extinct since the Eocene. The only known specimen had been collected in the Philippine waters, in 1908, at a depth of 200 m. During the next years, three oceanographical expeditions gave more adult specimens, allowing complete study of the species. From its morphology, it appeared that the status attributed to glypheids in the past in the classification of Decapoda Crustacea was quite erroneous. This group, until then considered as related to Palinurids (rock lobsters) was in fact much closer to Astacids (lobster, crayfish, etc.). In 1982, N. inopinata was recorded from the other side of Equator, from the Timor Sea. In October 2005, a second living species of glypheid was discovered southwest of New Caledonia. It was named Neoglyphea neocaledonica B. Richer de Forges, 2006. However, important and significant differences set apart the two species, especially the ornamentation of the cephalothorax, the conformation of the cephalic part and the proportions of epistom and thoracic appendages, being much more robust. It seems justified to establish, for the more recently described species, a new genus, Laurentaeglyphea, much closer to fossil forms. To cite this article: J. Forest, C. R. Biologies 329 (2006).

Homolidae de Haan, 1839 and Homolodromiidae Alcock, 1900 (Crustacea: Decapoda: Brachyura) from the Pacific Northwest of North America and a reassessment of their fossil records

New material collected from Cretaceous and Tertiary rocks of the Pacific Northwest of North America has prompted a reevaluation of the fossil record of the Homolidae de Haan, 1839 and the Homolodromiidae Alcock, 1900. The fossil records of the homolid generaHomolaLeach, 1815;HomolopsisBell, 1863; andHoplitocarcinusBeurlen, 1928 are restricted, andLatheticocarcinusBishop, 1988, which is synonymous withEohomolaCollins and Rasmussen, 1992 andMetahomolaCollins and Rasmussen, 1992, is reinstated as a distinctive genus. Thirteen new combinations resulted from reinstatement ofLatheticocarcinus: L. adelphinus(Collins and Rasmussen, 1992),L. affinis(Jakobsen and Collins, 1997),L. atlanticus(Roberts, 1962),L. brevis(Collins, Kanie, and Karasawa, 1992),L brightoni(Wright and Collins, 1972),L. centurialis(Bishop, 1992),L. declinata(Collins, Fraaye, and Jagt, 1995),L. dispar(Roberts, 1962),L. pikeae(Bishop and Brannen, 1992),L. punctatus(Rathbun, 1917),L. schlueteri(Beurlen, 1928),L. shapiroiBishop, 1988,L. spiniga(Jakobsen and Collins, 1997), andL. transiens(Segerberg, 1900). A new species,Latheticocarcinus ludvigseni, is described from Cretaceous rocks of British Columbia. The first fossil occurrence of the extant homolid genusParomolopsis, P. piersoninew species, is recorded from Miocene rocks of Oregon.Paromola pritchardiJenkins, 1977 is formally transferred toDagnaudusGuinot and Richer de Forges (1995) as suggested by Guinot and Richer de Forges (1995). The extinct family Prosopidae von Meyer, 1860 is referred to the Homolodromioidea Alcock, 1900, following previous work.Palehomola gorrelliRathbun, 1926 is transferred from the Homolidae to the Homolodromiidae, and the new genusRhinodromiais erected to containHomolopsis richardsoniWoodward, 1896, from Cretaceous rocks of British Columbia. A new terminology is suggested for describing the rostral area in homolodromiids, in an attempt to alleviate considerable confusion over that issue. The morphologic similarity of fossil and extant members in both the Homolidae and the Homolodromiidae suggest that these two brachyuran families are evolutionarily conservative, much as the lobsters are. In addition, the similar paleobiogeographic and evolutionary patterns seen in the two families suggests that either they are closely related or that brachyuran families exhibited similar evolutionary and dispersal trends early in their history.