Taxonomic and ecological interest in squat lobsters has grown considerably over the last two decades. A checklist of the 870 current valid species of squat lobsters of the world (families Chirostylidae, Galatheidae and Kiwaidae) is presented. The compilation includes the complete taxonomic synonymy and geographical distribution of each species plus type information (type locality, repository and registration number). The numbers of described species in the world's major ocean basins are summarised.

BENTHAUS, BIOCAL, Restreint, BORDAU 1, BORDAU 2, CHALCAL 2, CORAIL 2, Restreint, HALIPRO 2, Restreint, KARUBAR, MD32 (REUNION), MUSORSTOM 1, MUSORSTOM 10, MUSORSTOM 2, MUSORSTOM 3, MUSORSTOM 4, MUSORSTOM 5, MUSORSTOM 6, MUSORSTOM 7, MUSORSTOM 8, MUSORSTOM 9, NORFOLK 1, NORFOLK 2, SALOMON 1, SALOMON 2, SMCB, SMIB 3, SMIB 4, SMIB 5, SMIB 8, VOLSMAR

Two new species of the parasitic copepod genus Dissonus Wilson, 1906 are described: D. excavatus n. sp. from the gills of a labrid, Bodianus perditio, and a lutjanid, Macolor niger, collected off New Caledonia and Taiwan, and D. inaequalis n. sp. from a hemiscylliid elasmobranch, Chiloscyllium punctatum, collected off Sarawak (Malaysia) and the Philippines. Material of D. heronensis Kabata, 1966 is described from a balistid host, Pseudobalistes fuscus, off New Caledonia, and this constitutes a new host record for this parasite. D. manteri Kabata, 1966 was collected from four serranid host species off New Caledonia and from one of the same hosts off Taiwan. Two of the hosts from New Caledonia, Plectropomus laevis and Epinephelus cyanopodus, represent new host records. D. pastinum Deets & Dojiri, 1990 was recognised as a new synonym of D. nudiventris Kabata, 1966, so the total number of valid species is now twelve. Material from museum collections of D. nudiventris, D. similis Kabata, 1966 and D. spinifer Wilson, 1906 was re-examined and provided new information which is utilised in a key to all valid species of Dissonus.

BOA1

A multi‐gene ( SSU , LSU , psb A, and COI ) molecular phylogeny of the family Corallinaceae (excluding the subfamilies Lithophylloideae and Corallinoideae) showed a paraphyletic grouping of six monophyletic clades. Pneophyllum and Spongites were reassessed and recircumscribed using DNA sequence data integrated with morpho‐anatomical comparisons of type material and recently collected specimens. We propose Chamberlainoideae subfam. nov., including the type genus Chamberlainium gen. nov., with C. tumidum comb. nov. as the generitype, and Pneophyllum . Chamberlainium is established to include several taxa previously ascribed to Spongites , the generitype of which currently resides in Neogoniolithoideae. Additionally we propose two new genera, Dawsoniolithon gen. nov. (Metagoniolithoideae), with D. conicum comb. nov. as the generitype and Parvicellularium gen. nov. (subfamily incertae sedis ), with P. leonardi sp. nov. as the generitype. Chamberlainoideae has no diagnostic morpho‐anatomical features that enable one to assign specimens to it without DNA sequence data, and it is the first subfamily to possess both Type 1 ( Chamberlainium ) and Type 2 ( Pneophyllum ) tetra/bisporangial conceptacle roof development. Two characters distinguish Chamberlainium from Spongites : tetra/biasporangial conceptacle chamber diameter (<300 μm in Chamberlainium vs. >300 μm in Spongites ) and tetra/bisporangial conceptacle roof thickness (<8 cells in Chamberlainium vs. >8 cells in Spongites ). Two characters also distinguish Pneophyllum from Dawsoniolithon : tetra/bisporangial conceptacle roof thickness (<8 cells in Pneophyllum vs. >8 cells in Dawsoniolithon ) and thallus construction (dimerous in Pneophyllum vs. monomerous in Dawsoniolithon ).

KAVIENG 2014

PAPUA NIUGINI

CEAMARC-AA

A new species of beardfish, genus Polymixia, is described based on three specimens collected in Taiwanese waters and off the Chesterfield Islands of New Caledonia. It can be distinguished from its congeners by the following characters: dorsal-fin rays IV–V, 35–37; gill rakers on outer face of first gill arch 3+1+6=10; scales row between dorsal-fin origin and lateral line vertically 6–8 (S1) and posteriorly 12–14 (S2); pyloric caeca 40; snout rounded, with its surface rough and gelatinous, its tip evidently protrude anterior margin of premaxilla; ctenii on body scales arranged in a wedge-shape, forming three rows; 4th anal-fin spine long, 1.0%–1.2% eye diameter; longer dorsal-fin, 49.6–53.0% SL; blackish oral-branchial cavity. Our maximum-likelihood tree based on mitochondrial COI sequences revealed that the new species is distinct from six congeneric species. Our findings indicate the presence of at least six Polymixia species in Taiwan, highlighting Taiwan and adjacent areas as a region with the highest diversity of this genus.

EBISCO

A snake eel is described on the basis of a single specimen collected near Dongsha Atoll in the South China Sea. Its large eyes and the dorsal-fin origin behind the pectoral fins place it in the Ophichthus megalops group, despite its lack of a blackened anal-fin base in advance of the tail tip. The following combination of characters separates this new species from all of its Indo-West Pacific congeners: body bicoloured, grey-brown dorsally and uniformly pale ventrally; dorsal-fin origin situated 2.2 times pectoral-fin length behind tip of pectoral fin; eye large and snout short and blunt; a knob present between nostrils; rictus situated slightly anterior of vertical through posterior margin of eye; and teeth biserial on upper jaw and uniserial on vomer and lower jaw. A specimen of Ophichthus kusanagi Hibino, McCosker & Tashiro, 2019 was also collected nearby, representing the first record of this species from the South China Sea.

MUSORSTOM 4

30 new species in the Trichotropid CAPULIDAE in the genera Verticosta, Latticosta n. gen., Torellia and Trichosirius are described from tropical and subtropical deep water of Indo-Pacific and Atlantic Ocean: Verticosta ariane n. sp., Verticosta bellefontainae n. sp., Verticosta milleinsularum n. sp., Verticosta filipinos n. sp., Verticosta plexa n. sp., Verticosta lapita n. sp., Verticosta pyramis n. sp., Verticosta kanak n. sp., Verticosta vanuatuensis n. sp., Verticosta feejee n. sp., Verticosta lilii n. sp., Verticosta sinusvellae n. sp., Verticosta terrasesae n. sp., Verticosta uvea n. sp., Verticosta rurutuana n. sp., Verticosta bicarinata n. sp., Verticosta tricarinata n. sp., Verticosta quadricarinata n. sp., Verticosta cheni n. sp., Verticosta iris n. sp., Verticosta castelli n. sp., Verticosta biangulata n. sp., Verticosta reunionnaise n. sp., Verticosta lemurella n. sp., Verticosta madagascarensis n. sp., Latticosta guidopoppei n. sp., Latticosta tagaroae n. sp., Latticosta magnifica n. sp., Torellia loyaute n. sp. and Trichosirius omnimarium n. sp. Trichotropis townsendi is now Latticosta townsendi n. comb.. Shell material comes from expeditions by MNHN and collections of authors.

ATIMO VATAE, AURORA 2007, BATHUS 1, BATHUS 2, BATHUS 3, BATHUS 4, BENTHAUS, BENTHEDI, BIOCAL, BIOGEOCAL, BIOMAGLO, BIOPAPUA, BOA1, BORDAU 1, BORDAU 2, CONCALIS, EBISCO, EXBODI, GUYANE 2014, HALIPRO 1, INHACA 2011, KANACONO, KARUBAR, KAVIENG 2014, LAGON, LIFOU 2000, MADEEP, MADIBENTHOS, MD32 (REUNION), MIRIKY, MONTROUZIER, MUSORSTOM 10, MUSORSTOM 2, MUSORSTOM 3, MUSORSTOM 4, MUSORSTOM 6, MUSORSTOM 7, MUSORSTOM 8, NORFOLK 1, NORFOLK 2, PANGLAO 2005, PAPUA NIUGINI, SALOMON 1, SALOMON 2, SALOMONBOA 3, SANTO 2006, SMIB 8, Restreint, TAIWAN 2000, TARASOC, TERRASSES

The bathypelagic shrimp genus Pasiphaea Savigny, 1816 (Caridea: Pasiphaeidae) has been previously known from Taiwan from only three species. However, recent deep-sea surveys around the island have collected numerous specimens comprising ten species, of which four are new to science: P. aeons n. sp., P alcocki (Wood-Mason and Alcock, 1891), P exilimanus n. sp., P. falx n. sp., P japonica Omori, 1976, P. mclaughlinae Hayashi, 2006, P levicarinata Hanamura, 1994, P orientalis Schmitt, 1931, P. sirenkoi Burukovsky, 1987 and P. taiwanica n. sp. The four new species are fully described and illustrated, and compared with allied congeners. Pasiphaea orientalis is redescribed, as this species is endemic to Taiwan and its original description is inadequate. Amongst the three new records of Taiwan, P. levicarinata is also recorded for the first time from the northwestern Pacific.

TAIWAN 2000, TAIWAN 2001, TAIWAN 2003, TAIWAN 2004

The deep-sea genus Ephyrina Smith, 1885, is reported for the first time from Taiwan. The specimens obtained all belong to one species. The Taiwanese material closely resembles E. figueirai Crosnier & Forest, 1973, in having double rows of lateral spines on each side of the telson, but consistently differs from the nominotypical form from the Atlantic in having a longer and more spinose telson,while also the dorsal depression on abdominal somite VI is slightlymore pronounced. Comparison of additional specimens from the Philippines and from Madagascar shows that the West Pacific specimens are nearly identical, but the Madagascan material seems to have characters intermediate between theWest Pacific and Atlantic forms. We decided to propose a subspecific status to the West Pacific population, in order to emphasize the slight but constant differences observed in the telson in this obviously allopatric form of the species.

MUSORSTOM 1, MUSORSTOM 3

The galatheid genus Raymunida Macpherson and Machordom, 2000, is reported for the first time from Taiwan, and the species collected is also new to science. The new species is most closely related to R. confundens Macpherson and Machordom, 2001, but differs in having a more robust cheliped and walking legs covered with distinct squammae. ne coloration of the new species is probably unique in the germs by both the carapace and abdomen being uniform in color. Analysis of the mitochondrial cytochrome oxidase I gene sequences also supports the specific status of this Taiwanese form.

SMIB 3, SMIB 8, TAIWAN 2001

An undescribed species of the rare thalassinidean genus Calaxiopsis Sakai & de Saint Laurent, 1989 was found in samples obtained during a recent deep-sea survey off Taiwan. The new species, Calaxiopsis mclaughlinae n. sp., is unique within the genus in that the rostrum and telson each bear only one pair of spines, and in that the carapace bears a distinct median carina extending from the base of the rostrum to the cervical groove.

TAIWAN 2001, TAIWAN 2002

Two new species of Axioidea were found amongst the deep-sea material recently collected from New Caledonia. Meticonaxius dentatus sp. nov. is unique among members of the genus by the presence of the teeth on the rostrum and the merus of the large cheliped. Oxyrhynchaxius tricarinatus sp. nov. is the third species known in the genus and is unique in bearing three dorsal ridges on the abdome

BATHUS 1, BATHUS 2, BATHUS 3, BATHUS 4, HALIPRO 1, HALIPRO 2

Nihonotrypaea thermophila, new species, is described on the basis of 26 specimens from a hydrothermally influenced field off northeastern Taiwan at depths of 128–320 m. This is the first callianassid shrimp to be reported from deep-water hydrothermal vents, and available data seems to suggest that the new species is vent-endemic. The new species is assigned to Nihonotrypaea Manning & Tamaki, 1998, a genus including three previously described species inhabiting coastal mud or sand flat areas in Japan and its adjacent waters. The new species is unique in the genus in having the antennal peduncle distinctly longer than the antennular peduncle.

TAIWAN 2001

AURORA 2007, MAINBAZA

Recent advancements in deep-sea expeditions have made possible to sample adequate quantities of deep-sea organisms over wide geographical ranges for population genetic studies. Scalpellum stearnsii is a common stalked barnacle that occurs in the mesobenthic environment (>200 m depth) throughout the West Pacific Ocean and covers several major deep-sea basins. The present study examined the diversity and genetic differentiation of S. stearnsii populations from the East China Sea, West Philippine Basin, Sulu Sea, and Caroline Trenches. Mo­ lecular analyses based on partial sequences of the mitochondrial gene COI and nuclear gene H3 revealed four distinct clades of S. stearnsii—SS, CF1, CF2, and CF3—with distinct species-level pairwise divergences among the clades. SS (representing S. stearnsii, based on morphological comparison with holotype) is mainly present in the East China Sea and the Philippine Basin, CF1 is present in the East China Sea, CF2 is present in the Sulu Sea, and CF3 is exclusively present in the Caroline Trench (Southwest Pacific Ocean). Deep genetic differentiation be­ tween the northern (SS and CF1) and southern clades (CF2 and CF3) was estimated to have occurred around 33 million years ago, and the eastward-flowing Equatorial Undercurrent (100–200 m) and oxygen minimum zone (300–400 m) are the putative barriers to gene flow. The timing is concordant with reported diversification events in both shallow- and deep-water organisms during the Oligocene and Miocene periods. This cross-ocean, -taxon, and -habitat divergence time suggests speciation driven by global-scale events. Recent size expansion likely occurred in all the four clades and subsequent populations, predating the Last Glacial Maximum (LGM). The persistence of mesobenthic deep-sea barnacles through the temperature fluctuation at the LGM can be a common pattern.

BATHUS 2, BIOCAL, BIOPAPUA, BOA1, EBISCO, MUSORSTOM 10, MUSORSTOM 4, MUSORSTOM 5, MUSORSTOM 6, NORFOLK 1, NORFOLK 2, SALOMON 1, SMIB 2, SMIB 4, SMIB 8

Shallow-water tropical reefs and the deep sea represent the two most diverse marine environments. Understanding the origin and diversification of this biodiversity is a major quest in ecology and evolution. The most prominent and wellsupported explanation, articulated since the first explorations of the deep sea, holds that benthic marine fauna originated in shallow, onshore environments, and diversified into deeper waters. In contrast, evidence that groups of marine organisms originated in the deep sea is limited, and the possibility that deep-water taxa have contributed to the formation of shallowwater communities remains untested with phylogenetic methods. Here we show that stylasterid corals (Cnidaria: Hydrozoa: Stylasteridae)—the second most diverse group of hard corals—originated and diversified extensively in the deep sea, and subsequently invaded shallow waters. Our phylogenetic results show that deep-water stylasterid corals have invaded the shallow-water tropics three times, with one additional invasion of the shallow-water temperate zone. Our results also show that anti-predatory innovations arose in the deep sea, but were not involved in the shallow-water invasions.These findings are the first robust evidence that an important group of tropical shallow-water marine animals evolved from deep-water ancestors.

NORFOLK 2

Leptohelia flexibilis gen. nov. et sp. nov., the first stylasterid with a combined calcified and non-calcified skeleton, is described from seamounts and the slope off the islands of New Caledonia, in the southwestern Pacific. The new species is distinguished from all other species of the family Stylasteridae by having a non-calcified organic axis, internal to the basal portion of the calcified corallum. The internal axis is flexible and enclosed by a series of up to 10 calcified annuli, allowing passive lateral bending of the colony. Molecular phylogenetic analyses confirm that Leptohelia flexibilis is a stylasterid coral and reveal that the species is closely related to Leptohelia microstylus comb. nov., a southwestern Pacific stylasterid that lacks an internal axis.

BIOCAL, LAGON, MUSORSTOM 4, MUSORSTOM 5, MUSORSTOM 6, NORFOLK 2, SMIB 2

NORFOLK 2

A new deep-sea galatheid, Munidopsis dentifalx, is described on the basis of two specimens obtained at depths of 2,120-2,323 in by the PANGLAO 2005 expedition to the Philippines. The new species closely resembles M villosa Faxon, 1893, known from the Gulf of Panama and off Chile, but differs from that species in lacking antennal and epigastric spines on the carapace and a median spine on the abdominal segment 5, and in the spination of the P2-4 dactyli. The last mentioned character is unusual in the genus Munidopsis, the ultimate of the ventral marginal spines being far distant from the penultimate.

PANGLAO 2005

Squat lobsters of the family Munidopsidae are reported from deep-waters off the Philippines based on the material collected by the PANGLAO 2005 and AURORA expeditions. The material includes three species of the genus Galacantha A. Milne-Edwards, 1880 and 23 species of Munidopsis Whiteaves, 1874. Four species are described as new to science and nine species are recorded for the first time from the Philippines. Colour notes and illustrations from fresh specimens are provided for all the species. The poorly known species, Munidopsis ceratophthalma Alcock, 1901, is described in detail based on a Philippine specimen to supplement the original account of the species. Re-examination of the specimen previously reported as M. ceratophthalma from Taiwan reveals that it represents a new species, which is hereby described in this report.

AURORA 2007, CHALCAL 2, KARUBAR, MUSORSTOM 4, NORFOLK 2, PANGLAO 2005, SALOMON 1, SALOMON 2, TAIWAN 2000

A new pineapple fish is described based on 26 type and 80 non-type specimens collected from Taiwan, Vanuatu, the Solomon Islands, and Queensland, Australia. This new species is sympatric with and similar to Monocentris japonica but can be distinguished from the latter in having only 6 or 7 scales on the third scale row below the lateral line; excisura notched and a small pseudo-excisura present on the sagittal otolith; consistently greater head depth, body depth, postorbital length, dorsal-fin–pelvic-fin length, and dorsal-fin–pectoral-fin length in proportion to standard length. A detailed description and designation of neotype are provided for M. japonica. DNA barcoding analysis supports the distinction of the new species with an estimated average COI gene divergence of 3.6 % from M. japonica.

CHALCAL 1, CORAIL 2, EBISCO, SALOMONBOA 3, SANTO 2006, SMIB 3

The mantis shrimp superfamily Squilloidea, with over 185 described species, is the largest superfamily in the crustacean order Stomatopoda. To date, phylogenetic relationships within this superfamily have been comprehensively analysed using morphological data, with six major generic groupings being recovered. Here, we infer the phylogeny of Squilloidea using a combined dataset comprising 75 somatic morphological characters and four molecular markers. Nodal support is low when the morphological and molecular datasets are analysed separately but improves substantially when combined in a total-evidence phylogenetic analysis. We obtain a well resolved and strongly supported phylogeny that is largely congruent with previous estimates except that the Anchisquilloides-group, rather than the Meiosquillagroup, is the earliest-branching lineage in Squilloidea. The splits among the Anchisquilloides- and Meiosquilla-groups are followed by those of the Clorida-, Harpiosquilla-, Squilla- and Oratosquilla-groups. Most of the generic groups are recovered as monophyletic, with the exception of the Squilla- and Oratosquilla-groups. However, many genera within the Oratosquilla-group are not recovered as monophyletic. Further exploration with more extensive molecular sampling will be needed to resolve relationships within the Oratosquilla-group and to investigate the adaptive radiation of squilloids. Overall, our results demonstrate the merit of combining morphological and molecular datasets for resolving phylogenetic relationships.

ATIMO VATAE, KAVIENG 2014, MIRIKY

Recent expeditions have revealed high levels of biodiversity in the tropical deep-sea, yet little is known about the age or origin of this biodiversity, and large-scale molecular studies are still few in number. In this study, we had access to the largest number of solariellid gastropods ever collected for molecular studies, including many rare and unusual taxa. We used a Bayesian chronogram of these deep-sea gastropods (1) to test the hypothesis that deep-water communities arose onshore, (2) to determine whether Antarctica acted as a source of diversity for deep-water communities elsewhere and (3) to determine how factors like global climate change have affected evolution on the continental slope. We show that although fossil data suggest that solariellid gastropods likely arose in a shallow, tropical environment, interpretation of the molecular data is equivocal with respect to the origin of the group. On the other hand, the molecular data clearly show that Antarctic species sampled represent a recent invasion, rather than a relictual ancestral lineage. We also show that an abrupt period of global warming during the Palaeocene Eocene Thermal Maximum (PETM) leaves no molecular record of change in diversification rate in solariellids and that the group radiated before the PETM. Conversely, there is a substantial, although not significant increase in the rate of diversification of a major clade approximately 33.7Mya, coinciding with a period of global cooling at the EoceneOligocene transition. Increased nutrients made available by contemporaneous changes to erosion, ocean circulation, tectonic events and upwelling may explain increased diversification, suggesting that food availability may have been a factor limiting exploitation of deep-sea habitats. Tectonic events that shaped diversification in reef-associated taxa and deep-water squat lobsters in central Indo-West Pacific were also probably important in the evolution of solariellids during the Oligo-Miocene.

AURORA 2007, BENTHAUS, BERYX 11, BIOPAPUA, BOA1, BORDAU 1, CONCALIS, EBISCO, MAINBAZA, MIRIKY, NORFOLK 1, NORFOLK 2, PANGLAO 2004, PANGLAO 2005, SALOMON 1, SALOMON 2, TAIWAN 2001, TARASOC, TERRASSES

PAPUA NIUGINI