Gnathia trimaculata Coetzee, Smit, Grutter & Davis 2009

• Main Authors: Ota, Yuzo, Hirose, Euichi
• Format: Text
• Language: unknown
• Published: Zenodo 2009
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Malacostraca; Isopoda; Gnathiidae; Gnathia; Gnathia trimaculata; Antarctic; The Antarctic; Lizard Island; Antarc*
• Online Access: https://dx.doi.org/10.5281/zenodo.6214529; https://zenodo.org/record/6214529

Gnathia trimaculata Coetzee, Smit, Grutter & Davis, 2009 (Figs. 4, 5 B, C) Material examined. 5 males, 3 females, and 2 praniza larvae, from gill chambers of a blotched fantail ray Taeniura meyeni Müller & Henle, 1841, caught in gill net, Nakagusuku Bay (26 º N, 127 º E), Okinawa Island, Ryukyu Archipelago, Japan, 25 May 2007, coll. Y. Ota (NSMT-Cr 20427). 1 praniza larva from gills of the silky shark Carcharhinus falciformis (Bibron, 1839) caught in gill net, Nakagusuku Bay, 22 June 2006, coll. Y. Ota (NSMT-Cr 20428). 4 males, 2 females, and 1 unfed larva from the same locality and host as the above specimens, coll. Y. Ota (KMNH IvR 500, 415). 1 praniza larva from gill chamber of the whipray Himantura sp., caught in gill net, Nakagusuku Bay, 14 May 2007, coll. Y. Ota (KMNH IvR 500, 416). 1 male and 1 female, from gills of the Javanese cownose ray Rhinoptera javanica Müller & Henle, 1841, caught in gill net, Nakagusuku Bay, 16 May 2007, coll. Y. Ota (NMV J 46719). 2 praniza larvae from gill chambers of the whipray Himantura sp., caught in gill net, Nakagusuku Bay, 14 May 2007, coll. Y. Ota (NMV J 46720). Remarks. The size range of the males was 5.2–7.6 mm (mean ± SD; 6.17 ± 0.68 mm, n = 11), the size range of the females was 5.1–5.6 mm (5.41 ± 0.20 mm, n = 6) and the size range of the praniza larvae was 6.2–7.8 mm (7.03 ± 0.67 mm, n = 5). The male, female, and the larva of Gnathia trimaculata were described from the Great Barrier Reef, Australia (Coetzee et al ., 2009).The specimens of G. trimaculata from Ryukyus were larger than the ones from the GBR, the males (Fig. 4 A, B) from the Japanese fishes had higher number of setae (n = 21) on the external margin of peduncle 4 of antenna 2 than the GBR specimens. Female (Fig. 4 C–E): Article 3 of pylopod is more distinct then that of GBR specimens. Palp article 4 of maxilliped is not narrow. Praniza larva (Fig. 4 F): Some live specimens have no black spots. Brown lines present on lateral margins in alcohol. Discussion. The distribution range of G. trimaculata is fairly wide. Gnathiid larvae actively swim to attach the host fishes (Monod, 1926; Wägele, 1988) and host fishes’ movement or migration is thought to increase the distribution range of the gnathiids (Tanaka, 2007). Therefore, some larval gnathiids potentially disperse widely. In particular, some large host fishes have high mobility. A tiger shark Galeocerdo cuvier can move over 100 km per day (see Fig. 3 in Heithaus et al ., 2007) and migrated over 8000 km in 99 days (Heithaus et al ., 2007). Actually, twenty larvae of G. trimaculata attached gills of a tiger shark (total length; 160 cm) (Ota, unpublished data). Thus, G. trimaculata may extend their distributions by their host’s movement. : Published as part of Ota, Yuzo & Hirose, Euichi, 2009, Description of Gnathia maculosa and a new record of Gnathia trimaculata (Crustacea, Isopoda, Gnathiidae), ectoparasites of elasmobranchs from Okinawan coastal waters, pp. 50-60 in Zootaxa 2114 on page 57, DOI: 10.5281/zenodo.187941 : {"references": ["Coetzee, M. L., Smit, N. J., Grutter, A. S. & Davis A. J. (2009) Gnathia trimaculata n. sp. (Crustacea: Isopoda: Gnathiidae), an ectoparasite found parasitising requiem sharks from Lizard Island, Great Barrier Reef, Australia. Systematic Parasitology, 72, 97 - 112.", "Monod, T. (1926) Les Gnathiidae. Memories de la Societe des Sciences Naturelles du Maroc, 13, 1 - 668.", "Wagele, J. W. (1988) Aspects of the life-cycle of the Antarctic fish parasite Gnathia calva Vanhoffen (Crustacea: Isopoda). Polar Biology 8, 287 - 291.", "Heithaus, M. R., Wirsing A. J., Dill, L. M. & Heithaus L. I. (2007) Long-term movements of tiger sharks satellite-tagged in Shark Bay, Western Australia. Marine Biology, 151, 1455 - 1461."]}