Systematic Parasitology

, Volume 72, Issue 2, pp 97–112 | Cite as

Gnathia trimaculata n. sp. (Crustacea: Isopoda: Gnathiidae), an ectoparasite found parasitising requiem sharks from off Lizard Island, Great Barrier Reef, Australia

  • Maryke L. Coetzee
  • Nico J. SmitEmail author
  • Alexandra S. Grutter
  • Angela J. Davies


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.


Posterior Margin Simple Seta Lateral Margin Plumose Seta Reef Shark 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



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.


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Maryke L. Coetzee
    • 1
  • Nico J. Smit
    • 1
    Email author
  • Alexandra S. Grutter
    • 2
  • Angela J. Davies
    • 1
    • 3
  1. 1.Department of ZoologyUniversity of JohannesburgJohannesburgSouth Africa
  2. 2.School of Integrative BiologyThe University of QueenslandBrisbaneAustralia
  3. 3.School of Life Sciences, Faculty of ScienceKingston UniversityKingston upon ThamesUK

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