Gnathia trimaculata n. sp. (Crustacea: Isopoda: Gnathiidae), an ectoparasite found parasitising requiem sharks from off Lizard Island, Great Barrier Reef, Australia
- 129 Downloads
Gnathia trimaculata n. sp. is described from one black tip reef shark Carcharinus melanopterus Quoy & Gaimard and four grey reef sharks C. amblyrhynchos Bleeker collected off Lizard Island, Great Barrier Reef, Australia. Third-stage juveniles (praniza 3) were maintained in fresh seawater until they moulted into adults. Male adults emerged seven days post-removal (d.p.r) of pranizae from host fishes, whereas the female pranizae completed their moult into adult females 24 d.p.r. Distinctive features include the relatively large size of all stages and the unique mediofrontal process of the male, which is divided into two lobes forming a key-hole shape between them. The female frontal border is characterised by paired simple, pappose setae on the sides of the mid-dorsal area, as well as four long, pappose setae on the mid-dorsal region. The pranizae have eight teeth on each mandible. Live pranizae have stripes and three pairs of distinctive black spots within yellow circles on the sides of the pereonites and this pigmentation pattern persists in the adults. This represents the second description of a gnathiid parasitising elasmobranchs off Australia.
KeywordsPosterior Margin Simple Seta Lateral Margin Plumose Seta Reef Shark
Many thanks to the Lizard Island Research Station Staff, Will Robins (James Cook University, School of Marine and Tropical Biology, Townsville) and Tom Lisney (The University of Queensland, School of Biomedical Sciences, Brisbane) for collecting the sharks. This study was funded by an Australian Research Council Discovery Grant and the Sea and Coast II Programme of the National Research Foundation of Southern Africa.
- Coetzee, M. L., Smit, N. J., Grutter, A. S., & Davies, A. J. (2008). A new gnathiid from Australian sharks Gnathia grandilaris n. sp. (Crustacea, Isopoda, Gnathiidae) parasitizing two species of requiem sharks from Lizard Island, Great Barrier Reef, Australia. Journal of Parasitology, 94, 608–615.PubMedGoogle Scholar
- Cohen, B. F., & Poore, G. C. B. (1994). Phylogeny and biogeography of the Gnathiidae (Crustacea: Isopoda) with descriptions of new genera and species, most from South-Eastern Australia. Memoirs of the Museum of Victoria, 54, 271–397.Google Scholar
- Froese, R., & Pauly, D. (2008). Fishbase. World Wide Web electronic publication. www.fishbase.org, version (04/2008).
- McKiernan, J. P., Grutter, A. S., & Davies, A. J. (2005). Reproductive and feeding ecology of parasitic gnathiid isopods of epaulette sharks (Hemiscyllium ocellatum) with consideration of their role in the transmission of a haemogregarine. International Journal for Parasitology, 35, 19–27.PubMedCrossRefGoogle Scholar
- Nonumura, N., & Honma, Y. (2004). Gnathia capillata, a new species of the genus Gnathia (Crustacea, Isopoda) from Sado Island, the Sea of Japan. Contributions to Biological Laboratory of Kyoto University, 29, 343–349.Google Scholar
- Smit, N. J., Basson, L., & Van As, J. G. (2003). Life cycle of the temporary fish parasite, Gnathia africana (Crustacea: Isopoda: Gnathiidae). Folia Parasitologica, 50, 135–14.Google Scholar
- Svavarsson, J. (2006). New species of Gnathiidae (Crustacea, Isopoda, Cymnothoida) from seamounts off northern New Zealand. Zootaxa, 1173, 39–56.Google Scholar
- Watling, L. (1989). A classification system for crustacean setae based on the homology concept. In B. E. Felgenhauer, L. Watling, & A. B. Thistle (Eds.), Functional morphology of feeding and grooming in Crustacea. Vol. 6. Crustacean issues (pp. 15–26). Rotterdam: A. A. Balkema.Google Scholar