Animalia Isopoda Gnathiidae OtaYuzoErasmusAnjaGrutterAlexandra S.SmitNico J.Two new species and new host and distribution records of Gnathia Leach, 1814 (Crustacea, Isopoda, Gnathiidae) from Western Australia and the Great Barrier Reef, AustraliaZookeys05032024119312514410.3897/zookeys.1193.116538 B7DD0FDC-7DA8-5316-89D9-FE04156A3074 Gnathia grandilaris Coetzee, Smit, Grutter, & Davies, 2008 Gnathia grandilaris Coetzee, Smit, Grutter, & Davies, 2008: 608, 613, 614, figs 1–26. —Ota and Hirose 2009b, 43, 44, 51, 54, figs 5–7.Type locality.

Off Lizard Island (14°40'S, 145°27'E), Australia.

Material examined.

Australia •1♂ (7.1 mm TL, 6.6 mm BL); reared from a juvenile collected from P.sephen (TL and sex, unknown), Heron Island, GBR (23°26'32.9"S, 151°54'53.8"E), 9 July 1998, Ian D. Whittington leg. (QM W29826).

Remarks.

The original description of G.grandilaris was based on males reared from larvae found infesting a white tip reef shark, Triaenodonobesus (Rüppell, 1837), and grey reef sharks, C.amblyrhynchos, collected off Lizard Island, GBR (Coetzee et al. 2008) and subsequently reported from the Ryukyu Islands (Ota and Hirose 2009b; Ota 2015). The specimen from Heron Island corresponded well with the original description. This record constitutes a new host and a new locality record for G.grandilaris.

Distribution.

Lizard Island and Heron Island, Great Barrier Reef, Australia. Okinawa-jima Island, Kume-jima Island, Ishigaki-jima Island, the Ryukyu Islands, Japan.

Habitat of adults.

Unknown.

Hosts.

Three elasmobranch species from GBR: Triaenodonobesus (Rüppell, 1837), Carcharhinusamblyrhynchos (Bleeker, 1856), and Pastinachussephen (Forsskål, 1775). Seven elasmobranch species from Japan: Himantura sp., Himanturafai Jordan & Seale, 1906, Neotrygonorientalis Last, White & Séret, 2016 [Neotrygonkuhlii Müller & Henle, 1841 in Ota and Hirose 2009b and Ota 2015], Taeniurameyeni Müller & Henle, 1841, Mobulajapanica (Müller & Henle, 1841), Nebriusferrugineus (Lesson, 1831), Triaenodonobesus (Rüppell, 1837), and Negaprionacutidens (Rüppell, 1837).

Site of infection on host.

Gill chambers, interbranchial septa, gill filaments, and the floor of oral cavities. Rarely nostrils, body surface near the gill slits, or claspers.

OtaYHiroseE (2009b) Gnathianubila n. sp. and a new record of Gnathiagrandilaris (Crustacea, Isopoda, Gnathiidae) that parasitizes elasmobranchs from Okinawan coastal waters, Japan.Zootaxa2238(1): 43–55. https://doi.org/10.11646/zootaxa.2238.1.4CoetzeeMLSmitNJGrutterASDaviesAJ (2008) A new gnathiid (Crustacea, Isopoda) parasitising two species of requiem sharks from Lizard Island, Great Barrier Reef, Australia.The Journal of Parasitology94(3): 608–615. https://doi.org/10.1645/GE-1391.1OtaY (2015) Pigmentation patterns are useful for species identification of third-stage larvae of gnathiids (Crustacea: Isopoda) parasitising coastal elasmobranchs in southern Japan.Systematic Parasitology90(3): 269–284. https://doi.org/10.1007/s11230-015-9548-1