Review of the pilumnid crab genus Lophoplax Tesch, 1918 from the western Pacific, with descriptions of two new species, and the clarification of the identity of Pseudocryptocoeloma parvus Ward, 1936 (Crustacea: Brachyura).

The taxonomy of the pilumnid crab genus Lophoplax Tesch, 1918, is discussed. Lophoplax sculpta Stimpson, 1858) is redescribed and a neotype is selected in the interests of nomenclatural stability. Two new species allied to L. sculpta are described: L. sordida n. sp. from Indonesia, and L. pannosa n. sp. from Vanuatu. Pilumnus vermiculatus A. Milne-Edwards, 1873, is here transferred to Lophoplax. The poorly known Pseudocryptocoeloma parvus Ward, 1936 (type species of Pseudocryptocoeloma Ward, 1936), known only from Australia thus far, is redescribed and figured; and Pseudocryptocoeloma symmetrinudum Edmondson, 1951 (from Samoa and Japan), is transferred to Lophoplax.

A new genus and new species of Hymenosomatidae (Crustacea: Brachyura) from Indonesian Papua.

A new hymenosomatid crab, Chartocinus rarus n. gen. n. sp., is described from coastal waters in western Papua (formerly Irian Jaya) in Indonesia. The new genus superficially resembles Amarinus Lucas, 1980, but can easily be distinguished by its subquadrate third maxillipeds with the merus produced along the anteroexternal edge, elongate ambulatory legs, elongate male thoracic sternum, short male pleon without distinct intercalated plates on somite 5, and a short male first gonopod in which the inner margin is distinctly bilobed.

Diogenes matabiru, a new species of hermit crab from Lombok Island, Indonesia (Crustacea, Decapoda, Anomura, Diogenidae).

A new species of hermit crab, Diogenes matabiru, is described and illustrated on the basis of the specimens collected from mangrove environment in the eastern Lombok Island, Indonesia. This new species is related to D. pallescens Whitelegge, 1897 but differs in the shape of cheliped, telson and coloration in life. A key to the species of the genus Diogenes from Indonesia is also provided.

A synopsis of Typhlocarcinops Rathbun, 1909 (Crustacea: Decapoda: Brachyura: Pilumnidae), with descriptions of nine new species from the Indo-West Pacific.

The taxonomy of the Indo-West Pacific rhizopine genus Typhlocarcinops Rathbun, 1909 (Pilumnidae) is revised and 22 species are recognised. The identification of these small, soft sediment-dwelling crabs has been difficult because many of the types have never been figured and described to modern standards. The identity of the type species, T. canaliculatus Rathbun, 1909, is clarified and T. gallardoi Serène, 1964, is shown to be its junior synonym. Similarly, T. genkaiae Takeda Miyake, 1972, and T. takedai Ng, 1987, are synonymised with T. decrescens Rathbun, 1914, and T. marginatus Rathbun, 1914, respectively. Nine new species are described: T. robustus, T. hamus, T. raouli, T. atimovatae, T. hadrotes, T. hirtus, T. diminutus, T. kanashi and T. lapillus. The various species are defined by a suite of carapace, cheliped, third maxilliped, male pleonal and male first gonopod characters. The type and only known specimen of the poorly known rhizopine Paraselwynia ursina Tesch, 1918, which is superficially similar to Typhlocarcinops, is figured and compared. A key to all known species of Typhlocarcinops is provided.

Redescription of the little known hermit crab, Clibanarius clibanarius (Herbst, 1791) (Decapoda: Anomura: Diogenidae), based on material from southern India and type material.

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 immediately distinguishes C. clibanarius from C. infraspinatus. Although the species has been reported from wide areas in the Indo-West Pacific, records outside of India still needs to be verified.

Identity of the tree-spider crab, Parasesarma leptosoma (Hilgendorf, 1869 (Decapoda: Brachyura: Sesarmidae), with descriptions of seven new species from the Western Pacific.

The identity of the tree-spider crab, Parasesarma leptosoma (Hilgendorf, 1869) (family Sesarmidae), which is believed to be widely distributed in the Indo-West Pacific, is reassessed and shown to be a species-complex with nine species, seven of which are here described as new. Parasesarma leptosoma sensu stricto is now restricted to South and East Africa; and P. limbense (Rathbun, 1914) from Sulawesi, which had been regarded as a junior synonym, is here recognized as a valid species. The following species are described as new: P. gecko n. sp. from Vanuatu, Fiji, Guam and Japan; P. macaco n. sp. from Taiwan and the Philippines; P. kui n. sp. from Taiwan; P. parvulum n. sp. from the Philippines; P. gracilipes n. sp. from Indonesian Papua; P. purpureum n. sp. from Malaysia; and P. tarantula n. sp. from Sulawesi, Indonesia. The nine species of the Parasesarma leptosoma species-complex can be separated by the different shapes of their carapaces, the form of the dactylar tubercles on the male chelipeds, proportions of their ambulatory legs and the structure of the male first gonopod.

A revision of "blanket-hermit crabs" of the genus Paguropsis Henderson, 1888, with the description of a new genus and five new species (Crustacea, Anomura, Diogenidae).

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 blanket over its cephalic shield and part of cephalothoracic appendages, and thus the common name "blanket-crab". During a study of paguroid collections obtained during recent French-sponsored biodiversity campaigns in the Indo-West Pacific, numerous specimens assignable to Paguropsis were encountered. Analysis and comparison with types and other historical specimens deposited in various museums revealed the existence of five undescribed species. Discovery of these new species, together with the observation of anatomical characters previously undocumented or poorly described, including coloration, required a revision of the genus Paguropsis. The name Chlaenopagurus andersoni Alcock & McArdle, 1901, considered by Alcock (1905) a junior synonym of P. typica, proved to be a valid species and is resurrected as P. andersoni (Alcock, 1899). In two of the new species, the shape of the gills, length/width of exopod of maxilliped 3, width and shape of sternite XI (of pereopods 3), and armature of the dactyls and fixed fingers of the chelate pereopods 4, were found to be characters so markedly different from P. typica and other species discovered that a new genus for them, Paguropsinagen. n., is justified. As result, the genus Paguropsis is found to contain five species: P. typica, P. andersoni, P. confusasp. n., P. gigassp. n., and P. laciniasp. n. Herein, Paguropsinagen. n., is proposed and diagnosed for two new species, P. pistillatagen. et sp. n., and P. inermisgen. et sp. n.; Paguropsis is redefined, P. typica and its previously believed junior synonym, P. andersoni, are redescribed. All species are illustrated, and color photographs provided. Also included are a summary of the biogeography of the two genera and all species; remarks on the significance of the unusual morphology; and remarks on knowledge of the symbiotic anemones used by the species. To complement the morphological descriptions and assist in future population and phylogenetic investigations, molecular data for mitochondrial COI barcode region and partial sequences of 12S and 16S rRNA are reported. A preliminary phylogenetic analysis using molecular data distinctly shows support for the separation of the species into two clades, one with all five species of Paguropsis, and another with the two species Paguropsinagen. n.

Additions to the Indonesian crab fauna of the genus Mariaplax Rahayu Ng, 2014, and notes on Hexapus timika Rahayu Ng, 2014 (Crustacea, Decapoda, Brachyura, Hexapodidae).

Hexapus timika Rahayu Ng, 2014 is redescribed based on newly collected male and female specimens from Papua, Indonesia. Three new species from Jakarta Bay and Sunda Strait, Indonesia, are added to the genus Mariaplax, the richest genus in the family Hexapodidae, hitherto having 14 species. Mariaplax pitrai n. sp. has the carapace covered by small, closely-spaced tubercles and long ambulatory legs, resembling M. chenae Rahayu Ng, 2014 but easily separated by the position of female vulvae. Mariaplax hispida n. sp. is unique for the presence of short stiff setae on the outer face of the chelipeds and pereopods 2-4. Mariaplax sundaica n. sp. is characterized by the broad carapace, covered entirely by tubercles, the longitudinal grooves present only on the meri of pereopods 2 and 3. A key to the species of Mariaplax is provided.

A new species of the hermit crab genus Diogenes (Crustacea: Decapoda: Diogenidae) from the coast of KwaZulu-Natal, South Africa.

A new diogenid hermit crab with bright-white chelae, Diogenes albimanus n. sp., is described and illustrated, based on a single ovigerous female collected from KwaZulu-Natal, South Africa. The new species is compared to morphologically similar species, in particular to D. holthuisi and D. dorotheae, from which it is distinguishable by the shape and armature of the telson; and also to the superficially-similar South African D. extricatus, from which it differs by having the unarmed dorsal margins of the propodi and meri of the pereopods, as opposed to being armed with rows of strong spines. The unusually white chelae are similar in colour to those of D. takedai, but the coloration of all other parts is different in these two species. High quality macro photographs, a high-resolution microCT (µCT) scan of the whole animal, and the reference to the repository of the molecular barcode of the new species are provided.

Ankerius aenigmaticus, a new genus and new species of aphanodactylid crab symbiotic with polychaetes from the Red Sea coast of Saudi Arabia (Crustacea: Decapoda: Brachyura: Aphanodactylidae).

A new genus and new species of pinnotheroid crab of the family Aphanodactylidae, Ankerius aenigmaticus n. sp., is described from the Red Sea coast of Saudi Arabia. The genus is unusual among aphanodactylids in possessing more gaping third maxillipeds, strongly spiniform chelipeds and ambulatory legs, as well as a relatively longer ambulatory dactylus.

On the genera Selwynia Borradaile, 1903, and Gandoa Kammerer, 2006, with descriptions of two new species from Papua New Guinea and French Polynesia (Crustacea: Decapoda: Brachyura: Aphanodactylidae).

The taxonomy of the Indo-West Pacific aphanodactylid crabs Selwynia sibogae (Tesch, 1918) and S. edmondsoni (Rathbun, 1932) is discussed on the basis of the types, and both species are redescribed and figured. Two new species from Papua New Guinea and French Polynesia respectively, are described and compared with congeners. All are symbionts in polychaete tubes. A key to the genus Selwynia is also provided. The poorly known genus Gandoa Kammerer, 2006, is redescribed on the basis of the rediscovered the type species, Voeltzkowia zanzibarensis Lenz, 1905. The lectotype female of Pinnixa brevipes H. Milne Edwards, 1853, is examined and shown to be a senior subjective synonym of G. zanzibarensis.

Notes on Hexapodidae (Crustacea, Brachyura) from Indonesia and Malaysia, with description of a new species of Mariaplax Rahayu & Ng, 2014, from Lombok, Indonesia.

The male of Hexapinus latipes (De Haan, 1835), so far known only from female specimens, is described based on the material reported by De Man (1888) as "Hexapus sexpes". Material referred to "Hexapus sexpes" by Tesch (1918) is shown instead to belong to Hexapinus simplex Rahayu & Ng, 2014, and Hexapinus latus Rahayu & Ng, 2014, while his "Hexaplax megalops Doflein, 1904" belongs to Hexaplax aurantium Rahayu & Ng, 2014. A new species, Mariaplax aspera n. sp., is described from a female collected in Lombok, Indonesia. This new species most closely resembles M. narusei Rahayu & Ng, 2014, described from Japan, but differs by its relatively narrower carapace, shorter ambulatory legs, tuberculated third maxillipeds, and shorter telson.

On some interesting marine decapod crustaceans (Alpheidae, Laomediidae, Strahlaxiidae) from Lombok, Indonesia.

Several rare or uncommon, mostly infaunal decapod crustaceans are reported from intertidal and shallow subtidal habitats of Lombok, Indonesia. The alpheid shrimps Alpheus angustilineatus Nomura & Anker, 2005, Athanas shawnsmithi Anker, 2011, Jengalpheops rufus Anker & Dworschak, 2007, Salmoneus alpheophilus Anker & Marin, 2006, Salmoneus colinorum De Grave, 2004, and the laomediid mud-shrimp Naushonia carinata Dworschak, Marin & Anker, 2006, are reported for the first time since their original descriptions and represent new records for the marine fauna of Indonesia. The alpheid shrimps Alpheus macellarius Chace, 1988, Alpheus platyunguiculatus (Banner, 1953), Athanas japonicus Kubo, 1936, Athanas polymorphus Kemp, 1915, Leptalpheus denticulatus Anker & Marin, 2009, Richalpheus palmeri Anker & Jeng, 2006, Salmoneus gracilipes Miya, 1972, Salmoneus tricristatus Banner, 1959 and the laomediid mudshrimps Laomedia astacina De Haan, 1841 and Naushonia lactoalbida Berggren, 1992 are new records for Indonesian waters. The remaining alpheid shrimps, namely Alpheopsis yaldwyni Banner & Banner, 1973, Alpheus savuensis De Man, 1908, Automate anacanthopus De Man, 1910, Automate dolichognatha De Man, 1888, Salmoneus serratidigitus (Coutière, 1896), and the strahlaxiid mud-shrimp Neaxius glyptocercus (von Martens, 1869), all previously known from Indonesia, are recorded for the first time from Lombok. Colour photographs are provided for all species reported, some shown in colour for the first time. 

Pagurus Asper H. Milne Edwards, 1848, a subjective synonym of Clibanarius longitarsus (De Haan, 1849) and reversal of precedence (Crustacea: Decapoda: Anomura: Diogenidae).

The species-group name Pagurus longitarsus was proposed by De Haan (1849: 211, pl. 50, fig. 3) for a species of hermit crab collected from Japan (see Yamaguchi & Baba 1993: 272, 273). Dana (1852b: 464) transferred Pagurus longitarsus to the genus Clibanarius Dana, 1852 (first established in Dana 1852a). Dana (1852b: 464) also suggested that Pagurus longitarsus De Haan, 1849, and Pagurus asper H. Milne Edwards, 1848, were possibly synonymous by listing "Pagurus asper ? Edwards, Ann. des Sci. Nat., 1848(3), v. [sic] 62" in the synonymy of Pagurus longitarsus De Haan, 1849. Fize & Serène (1955: 72) repeated Dana's (1852b: 464) opinion regarding the synonymy Pagurus longitarsus and Pagurus asper. McLaughlin (2002: 399) and McLaughlin et al. (2010: 20) also considered Pagurus longitarsus De Haan, 1849, and Pagurus asper H. Milne Edwards, 1848, to be possibly conspecific, but considered Clibanarius longitarsus (De Haan, 1849), to be the valid name.

Revision of the family Acidopsidae Stevcic, 2005, and the systematic position of Typhlocarcinodes Alcock, 1900, Caecopilumnus Borradaile, 1902, and Raoulia Ng, 1987, with descriptions of two new genera and five new species (Crustacea: Brachyura: Goneplacoidea).

The family Acidopsidae Stevcic, 2005, is revised; and two subfamilies are recognised. The Acidopsinae Stevcic, 2005, is characterised by the coxal male opening, a quadrate basal antennal article and vulvae arranged near the median longitudinal thoracic sternal groove. Three genera are included in the Acidopsinae: Acidops Stimpson, 1871 (with two species), Parapilumnus Kossmann, 1877 (with two species) and Crinitocinus gen. nov. (monotypic for Pilumnus alcocki Borradaile, 1902). The Raouliinae Stevcic, 2005 (= Typhlocarcinodidae Stevcic, 2005; Caecopilumnidae Stevcic, 2011), is characterised by its coxo-sternal male opening, a short basal antennal article which is distinctly wider than long and vulvae arranged submedially on thoracic sternite 6. Four genera are included in the Raouliinae: Raoulia Ng, 1987 (with five species, three of which are described as new), Caecopilumnus Borradaile, 1902 (with three species of which one is described as new), Typhlocarcinodes Alcock, 1900 (monotypic) and Thecaplax gen. nov. (for one new species). 

A new species of the pagurid hermit crab genus Lophopagurus McLaughlin, 1981 (Crustacea: Decapoda: Anomura) from French Polynesia, and additional record of L. indonesiensis McLaughlin, 1997 from the Philippines.

Two species of the pagurid hermit crab genus Lophopagurus McLaughlin, 1981 are reported herein. Lophopagurus (Lophopagurus) minimus n. sp., described on the basis of two females from Tuamotu Archipelago, French Polynesia, appears closest to L. (L.) nanus (Henderson, 1888), but is easily distinguished from the latter by the different shape of the ocular peduncles and the less developed armature of the right cheliped. A single female from the Bohol Sea, the Philippines, is identified with L. (Australeremus) indonesiensis McLaughlin, 1997, a species for which possible synonymy with L. (A.) triserratus has been suggested. The newly collected specimen confirms the validity of the species and represents its second record since the original description.