A new species of Cirolana Leach, 1818 (Isopoda, Cymothoidea, Cirolanidae), from Havelock Island, Andaman Sea, northern Indian Ocean.

Cirolana swaraj sp. nov. was collected from brackish-water Neil Lagoon on Havelock Island, South Andaman and is described and illustrated in detail. Cirolana swaraj sp. nov. can be distinguished by: frontal lamina 2.2 times as long as greatest width, lateral margins slightly widening to rounded anterior margin; pereonite 1 dorsal anterior mid-region with convex boss covered with fine ridges, pereonites 17 each with a single transverse impressed line, posterior margin with 18, 18, 17 and 12 tubercles on pereonites 47 dorsal posterior margins respectively; pleonites 45 each with prominent median tubercle, 4 and 2 tubercules on each side of pleonites 45; pleotelson dorsal surface with sub-median double row of 5 tubercules, posterior lateral margins straight, posterior margin narrowly rounded with 6 robust setae and plumose marginal setae extending anteriorly to mid-length; uropodal exopod lateral margin with eight robust setae and a continuous row of plumose marginal setae. A key to the marine and estuarine genera of Cirolanidae of the northern Indian Ocean is given.

A new species of deep-sea Booralana Bruce, 1986 (Crustacea: Isopoda: Cirolanidae) from The Bahamas, Western North Atlantic.

Booralana nickorum sp. nov. is described from the deep-water slope of the Exuma Sound, The Bahamas, from depths of 540 to 560 metres. It is the fourth species to be assigned to the genus and the second species described from the Western North Atlantic. The species can be distinguished from Booralana tricarinata Camp and Heard, 1988 and the other species by the sub-triangular pleotelson and the uropodal exopod of mature males being far longer than endopod, with both rami extending well beyond the posterior margin of the pleotelson. Additionally, pleopods 3 and 4 lack a prominent angle at midpoint of ramus.

Cassidinidea andamanensis sp. nov., a new species of intertidal Sphaeromatidae (Crustacea: Isopoda) from the Andaman Islands, northern Indian Ocean.

Cassidinidea andamanensis sp. nov. was collected from intertidal habitats on the coast of South Andaman, Andaman Islands, India and is described and illustrated in detail. Cassidinidea andamanensis sp. nov. the second definitive record of the genus from India, is characterized by: smooth body surface, prominently convex epistome anterior margin, pleotelson dorsal smooth surface and the posterior margin is subtruncate and weakly convex with small setae, the appendix masculina posterior margin is narrowly rounded.

DNA barcoding of the supergiant isopods from Bathynomuskensleyi Lowry & Dempsey, 2006 (Cirolanidae) and a molecular biology comparison of B.jamesi Kou, Chen & Li, 2017.

DNA was extracted from tissue samples from specimens of newly-collected Bathynomuskensleyi from Queensland and subsequently the COI and 16S rRNA sequences were successfully cloned. The holotype of B.kensleyi was also sampled for COI only. Comparison of the sequences showed that, for the COI sequences, B.jamesi and B.kensleyi have more than 59 different DNA positions amongst 596 known reading sequences. The Kimura two parameter (K2P) distance analysis confirmed that B.jamesi and B.kensleyi are two species. Indian records of Bathynomus are reviewed and three of the four identified species from India are shown to be misidentifications. Bathynomusdecemspinosus, B.doederlini and B.kensleyi are found to not occur in India and the only accepted record is that of Bathynomuskeablei Lowry & Dempsey, 2006. We conclude that, based on molecular analysis and morphological comparisons, the correct species identity of Indian species other than Bathynomuskeablei remains unknown.

A new species of Corallana Dana, 1852 (Crustacea: Isopoda: Corallanidae) from the Andaman Islands, northern Indian Ocean.

Corallana mishrai sp. nov. collected from dead mangrove roots at Kodiyaghat, South Andaman, Andaman Islands, India is described and illustrated in detail. Corallana mishrai sp. nov. the first definitive record of the genus from India, is characterized by: frontal lamina with short straight (or very weakly convex) lateral margins and the anterior margin forming a strong acute median point; pleotelson length 0.76 greatest width, posterior margin with 5 robust setae; uropodal exopod 7 times longer than greatest width, extending beyond endopod by one fourth of its length; endopod lateral margin slightly convex with 4 RS and PMS, apex forms a slightly obtuse angle with long simple setae, mesial margin weakly convex with 2 RS and PMS; mandible bidentate; transverse row of 6 tubercles present on pereonite 1 and pleonites 2, 3 and 4 lacking lateral tubercles. The status of the genus and its species are reviewed, and two species are transferred to new combinations: Argathona kulai (Bruce, 1982) comb. nov. and Tachaea bidentata (Jones et al. 1983) comb. nov.

A review of the family Cymothoidae (Isopoda: Cymothooidea) infesting marine fishes from Malaysian waters, with new host and geographical records.

A checklist of parasitic cymothoids from Malaysian waters is presented based on available literature and material collected from 2010 to 2020. Most of the collected specimens were recorded from waters of Terengganu, east coast of Peninsular Malaysia (facing the South China Sea), whereas literature records were included from Sarawak, along the Miri coast of northwest Borneo. The checklist comprises 19 species in ten genera, seven of which are new records from Malaysia: Anilocra nemipteri Bruce, 1987; Ceratothoa barracuda Martin, Bruce & Nowak, 2015; Ceratothoa carinata (Bianconi, 1869); Cymothoa epimerica Avdeev, 1979; Elthusa sigani Bruce, 1990; Joryma engraulidis (Barnard, 1936) and Renocila richardsonae Williams & Bunkley-Williams, 1992. Eight new host records are based on collected specimens: Anilocra nemipteri was dorsally attached on Nemipterus nemurus (Bleeker, 1857), Nemipterus nematophorus (Bleeker, 1854), Nemipterus tambuloides (Bleeker, 1853) and Nemipterus thosaporni Russell, 1991 (family Nemipteridae); Ceratothoa carinata was found in the buccal cavity of Decapterus macrosoma Bleeker, 1851 (family Carangidae); Cymothoa eremita (Brunnich, 1783) was attached in the buccal cavity of Nemipterus tambuloides (Bleeker, 1853) and Nemipterus furcosus (Valenciennes, 1830); Elthusa sigani was found attached on the gills of Pterois russelli Bennett, 1831 (family Scorpaenidae), and Renocila richardsonae was attached on the caudal fin of Upeneus japonicus (Houttuyn, 1782) (family Mullidae). All cymothoid species listed here are known to have a Central Indo-Pacific distribution, with some ranging as far as the Western Indian Ocean. A cymothoid-host association is here listed from 28 fish families, with the most commonly reported from Carangidae (pompanos, jack mackerels, runners, scads), Engraulidae (anchovies), and Leiognathidae (ponyfishes, slipmouths). This paper is the first comprehensive review of both verified literature records and deposited specimens. A key for the family of Cymothoidae in Malaysian waters is given.

A Taxonomic Review of the Buccal-attaching Fish Parasite genus Lobothorax Bleeker, 1857 (Crustacea: Isopoda: Cymothoidae) with Description of a New Species from Southwestern India.

The genus Lobothorax Bleeker, 1857 is revised with the description of a new species collected from the gempylidaen fish Promethichthys prometheus (Cuvier, 1832) from the southwestern coast of India. A revised generic diagnosis is provided based on the redescription of the type species. Lobothorax aurita (Schioedte and Meinert, 1883) is here synonymised with Lobothorax typus Bleeker, 1857 based on the original description. Lobothorax nicosmiti Aneesh, Bruce and Kumar sp. nov. is described from the female stage and it is characterized by: pereonite 1 anterolateral expansion not extending to the anterior margin of cephalon; coarsely pitted pereonites dorsal surfaces; pereonites without dorsal median longitudinal ridges; anteriorly truncate cephalon; pleotelson about 0.6 times as long as wide, posterior margin weakly emarginate, broadly sub-truncate, lateral margins convex; maxilliped palp article 3 with three RS; pereopods basis much wider with prominent carina. A key to the species of Lobothorax Bleeker, 1857 is presented.

Redescription of Gnorimosphaeroma oregonense (Dana, 1853) (Crustacea, Isopoda, Sphaeromatidae), designation of neotype, and 16S-rDNA molecular phylogeny of the north-eastern Pacific species.

Gnorimosphaeroma oregonense (Dana, 1852) is revised, a male neotype is designated, photographed, and illustrated; the species occurs from Vancouver British Columbia to the central California coast. 16S-rDNA sequences (~650 bp) for all available ethanol preserved species of Gnorimosphaeroma were used to hypothesize their relationships. Our analyses revealed a sister taxon relationship between the fully marine G. oregonense and the brackish to freshwater species, G. noblei. The oyster associated and introduced G. rayi is sister to a previously not recognized or identified, but genetically distinct, Gnorimosphaeroma sp. collected at two sites in San Francisco Bay. Gnorimosphaeroma sp. is probably also a western Pacific species based on its genetic relationship to G. rayi. Photographic comparisons are offered for G. oregonense (marine), G. noblei (freshwater), G. rayi (introduced), G. sp. (presumably introduced), and G. insulare (San Nicolas Island). Records of the holdings at the Los Angeles County Museum of Natural History are summarized. Without material available north of Vancouver through Alaska, the range of G. oregonense could not be genetically verified. This review includes a diagnosis and description of the genus Gnorimosphaeroma Menzies, 1954.

Two new species of branchial fish parasitic isopod of the genus Mothocya Costa, in Hope, 1851 (Isopoda, Cymothoidae) from Nigeria.

The branchial attaching, fish parasitic genus Mothocya Costa, in Hope, 1851 is recorded for the first time from Nigerian brackish waters on Monodactylus sebae (Perciformes: Monodactylidae). Mothocya andoni n. sp. is characterised by a trapezoid-shaped cephalon with a subtruncate rostrum; pereonite 1 anterolateral angles only reaching to the posterior margin of the eyes; particularly large and wide coxa 7 extending to pleonite 4; pereopod 7 with a narrow basis; broadly rounded pleotelson; and uropods extending to the pleotelson posterior margin, with subequal rami. Mothocya powelli n. sp. is characterised by its small size (7 mm); a posteriorly ovoid body shape; cephalon anterior margin truncate; a short pleon with pleotelson lateral margins converging to a narrowly rounded apex; pleonite lateral margins overlapped by pereonite 7; slender uropods that extend to the posterior margin of the pleotelson with the uropodal exopod almost double the length of the endopod.

Two new species of the marine isopod genus emCirolana/em Leach, 1818 (Crustacea: Isopoda: Cirolanidae) from the coast of the western Gulf of Thailand.

Cirolana khamensis sp. nov. and C. parawongat sp. nov. are described from specimens collected in the western Gulf of Thailand at depths of 8 metres and 1 metre, respectively. Both species belong to the Cirolana 'pleonastica-group' with tubercles on the dorsal surfaces, transverse sutures on the pereonites, pleonite 3 not posteriorly produced and pleonite 4 posterolaeral margin rounded. Cirolana khamensis sp. nov. can be distinguished from other species of Cirolana 'pleonastica-group' by lateral margin of uropodal exopod having five robust seatae and a continuous row of plumose marginal setae, pereonites 1-3 each with a single transverse impressed line; antennula peduncle with articles 1 and 2 distinct and articulated peduncle; pleotelson dorsal surface with two sub-median longitudinal carinae, each of which has four prominent tubercles. Cirolana parawongat sp. nov. can be distinguished by pereonites 1-3 without a single transverse impressed line and having nine tubercles on pleonite 4 and 5. A dichotomous key to Cirolana 'pleonastica-group' in South-East Asia region is given.

Aegiochus gracilipes (Hansen, 1895) a senior synonym of Aegiochus tara Bruce, 2009 (Crustacea: Isopoda: Aegidae).

Aegiochus gracilipes Hansen, 1895 was described from a single immature specimen accompanied by three figures (Hansen 1895). Hansen (1916) subsequently reported the species without figures. Over the next 100 years A. gracilipes only appeared in the literature as a citation in larger review and cataloguing studies. Most significantly, Bruce (2009) transferred A. gracilipes from Aega Leach, 1815 to Aegiochus Bovallius, 1885, as part of a broader study redefining the morphological characters used to distinguish Aegiochus. To the present day A. gracilipes, described from the north-eastern Atlantic off the Outer Hebrides, Scotland, is known only from the original figures and its limited primary description.

A new species of the mesopelagic isopod genus Xenuraega Tattersall, 1909 (Crustacea: Isopoda: Aegidae) from Japan, the second species in the genus.

Xenuraega bythionekta sp. nov., is described from a single specimen taken off southern Japan. It is the second species of Xenuraega Tattersall, 1909, and extends the known range of the genus from North Atlantic to the northern Pacific Ocean. The species is characterized by the posteriorly narrowed pleotelson, and both uropodal rami being elongate and provided with a mass of long plumose setae. Xenuraega bythionekta sp. nov. is known only from the type locality, Kagoshima Prefecture, southern Japan at a depth of 1178-1179 m.

New gnathiid isopod crustaceans (Cymothoida) from Heron Island and Wistari Reef, southern Great Barrier Reef.

Eleven species including six new species of Gnathiidae (Crustacea, Isopoda, Cymothoida) are reported from the Heron Island and Wistari Reef, Capricorn Group, southern Great Barrier Reef: Elaphognathia queenslandica sp. nov., Gnathia acrorudus sp. nov., Gnathia capricornica sp. nov., Gnathia carinodenta sp. nov., Gnathia formosa sp. nov. and Gnathia glaucostega sp. nov. Gnathia cornuta Holdich Harrison, 1980 and Gnathia grutterae Ferreira, Smit Davies, 2010 are for the first time reported from Heron Island and new records from Heron Island are provided for Gnathia biorbis Holdich Harrison, 1980, Gnathia variobranchia Holdich Harrison, 1980, and Gnathia wistari Svavarsson Bruce, 2012.

A new genus and species of fish parasitic cymothoid (Crustacea, Isopoda) from the Indian Ocean coast of South Africa, with a key to the externally attaching genera of Cymothoidae.

Bambalocra intwala gen. et sp. nov. is described from Sodwana Bay, north-eastern South Africa. The monotypic genus is characterised by the broadly truncate anterior margin of the head with a ventral rostrum, coxae 2-5 being ventral in position not forming part of the body outline and not or barely visible in dorsal view, and the posterolateral margins of pereonites 6 and 7 are posteriorly produced and broadly rounded. The antennulae bases are widely separated, with both antennula and antenna slender. The species is known only from the type locality and the known hosts are species of Pomacanthidae (Angelfish). A revised key to the externally attaching genera of Cymothoidae is provided.

The first record of Gnathostenetroididea Kussakin, 1967 from Australian waters with description of four new species of Gnathostenetroides Amar, 1957 (Crustacea: Isopoda: Asellota) from the Great Barrier Reef.

The asellote family Gnathostenetroididae Kussakin, 1967 is reported for the first time from Australian waters. Four new species of Gnathostenetroides Amar, 1957 from the Great Barrier Reef are described. The genus Maresiella Fresi and Scipione, 1980 is here placed into synonymy with Gnathostenetroides and a new diagnosis is given for Gnathostenetroides together with a key to the 12 species and a map of the distribution of the genus. The genus Dignatroides Stock and Vonk, 1990 is placed into synonymy with Caecostenetroides Fresi and Schiecke, 1968, and a new composition of the family Gnathostenetroididae, the updated diagnosis and a key to the three genera are provided.

Two new species and a new record of Metacirolana Kussakin, 1979 (Crustacea: Isopoda: Cirolanidae) from Indonesia.

Two new species of Metacirolana from coral reefs in Indonesia are described and Metacirolana spinosa (Bruce, 1980) is recorded for the first time in Indonesia. Metacirolana lombok sp. nov. and Metacirolana mioskon sp. nov. show similarities with several other species of Metacirolana forming a species group within the genus, characterized by small body size (2.0-3.5 mm), smooth body surfaces, weakly produced rostrum, lack of dorsal carinae and abundant chromatophores.

Cirolana bambang, a distinctive new species of Cirolana Leach, 1818 (Crustacea: Isopoda: Cirolanidae) from Bitung, Indonesia.

Cirolana bambang sp. nov. from Bitung, North Sulawesi, Indonesia is described. The species can be recognised by generally smooth body with small, acute, submedian nodules on pleonites 4-5 and the anterior dorsal surface of the pleotelson together with a flat, pentagonal frontal lamina, linguiform and sexually dimorphic pleotelson with the dorsal surface covered by short setae in males, deeply bifid uropod apices, and a conspicuously large robust seta on the superodistal angle of pereopod 1 ischium. Cirolana bambang sp. nov. appears to belong to a group of Indo-West Pacific Cirolana with prominent penial process, a large robust seta on the superodistal angle of pereopod 1 ischium and the presence of setae on dorsal surface of pleotelson and or uropod in males. The most similar species are Cirolana comata Keable, 2001; Cirolana dissimilis Keable, 2001; Cirolana aldabrensis Schotte Kensley, 2005; and Cirolana somalia Schotte Kensley, 2005. Cirolana kiliani Müller, 1993 and C. somalia are found not to belong to the Cirolana'parva-group'.

Three new species of Tridentella Richardson, 1905 (Isopoda: Cymothoida: Tridentellidae) from New Caledonia.

Three new species of Tridentella Richardson, 1905 are described from the New Caledonia region. All three species are smooth bodied or largely smooth bodied, and all were collected from the shelf around New Caledonia at depths from 150-760 metres. Tridentella palmata sp. nov. is characterised by pereopod 4 having numerous large robust setae on the carpus and an exceptionally long dactylus (7.0 times as long as proximal width); Tridentella katlae sp. nov. is the only species in the genus with medially united eyes that fill the head in dorsal view; Tridentella magna sp. nov. is the largest species in the genus (36 mm) and can be identified by the head having an anterior submarginal ridge and three submarginal tubercles on the poster margin. Tridentella takedai Nunomura 2006 (off Arasaki, Hokusuka-Shi, Kyushu, Japan) is formally transferred to Alcirona Hansen, 1905, forming Alcirona takedai (Nunomura, 2006) comb. nov.

The first records of Stenobermuda Schultz, 1982 and Tenupedunculus Schultz, 1979 from Australia, with description of two new species from the Great Barrier Reef (Isopoda, Asellota, Stenetriidae).

The genera Tenupedunculus Schultz, 1982 and Stenobermuda Schultz, 1979 are recorded for the first time from beyond the Southern Ocean, at the Great Barrier Reef, Australia. Tenupedunculus serrulatussp. n. and Stenobermuda waroogasp. n. are described from Heron Island and Lizard Island respectively, both in the Great Barrier Reef. The genus Tenupedunculus is revised and a new diagnosis presented, with Tenupedunculus virginale Schultz, 1982, T. pulchrum (Schultz, 1982), and T. serrulatussp. n. being retained within the genus, and the remaining species here regarded as Stenetriidae incertae sedis (eight species).

Cirolana phuketensis, a new species of marine isopod (Crustacea, Isopoda, Cirolanidae) from the Andaman Sea coast of Thailand.

Cirolana phuketensissp. n. was collected from coral rubble from the Andaman sea coast of Thailand. C. phuketensissp. n. is described and fully illustrated; C. phuketensissp. n. can be recognized by the presence of transverse sutures on pereonites 2-4, pereonite 7 having three transverse sutures forming a nodulose ridge, antennula peduncle with articles 1 and 2 fully fused; pleotelson dorsal surface with 2 sub-median longitudinal carinae, each of which has one prominent tubercle, lateral margins weakly convex, and posterior margin narrow and rounded; 6 molariform robust setae pereopod 1 on inferior margin of merus and the penial openings are two low tubercles. A dichotomous key to species of Cirolana in Thailand is given.