Cymothoa bychowskyi Avdeev, 1979

Ravichandran, S., Vigneshwaran, P. & Rameshkumar, G., 2019, A taxonomic review of the fish parasitic isopod family Cymothoidae Leach, 1818 (Crustacea: Isopoda: Cymothooidea) of India, Zootaxa 4622 (1), pp. 1-99 : 18-19

Cymothoa bychowskyi Avdeev, 1979

( Fig. 1 j–l)

Cymothoa bychowskyi Avdeev, 1979a: 230 , pl. 6, 7; 1985: 217, fig. 1.— Trilles, 1994: 138.—Williams, Bunkley-Williams & Pitlik, 2000: 157.— Kensley, 2001: 232.— Bruce, Lew Ton & Poore, 2002: 174.—Paulay, Kropp, Ng & Eldredge, 2003: 479.— Trilles & Bariche, 2006: 228.— Rameshkumar, Ravichandran, Sivasubramanian & Trilles, 2013d: 42, fig. 1c.— Martin, Bruce & Nowak, 2016: 6 .

Type and type locality. The holotype Cymothoa bychowskyi , held at Russian Pacific Federal Fisheries Research Institute, Vladivostok ( TINRO АGK 75011) from northwestern Australia, red cornetfish Fistularia petimba Lacépède, 1803 .

Material examined. 1 ovig. female (27 mm), Agatti Island, Lakshadweep, 20 April 2011, from Strongylura leiura (Bleeker, 1850) , coll. G. Rameshkumar ( CAS / MBRM C- 87).

Reamarks. Cymothoa bychowskyi can be identified by the body 2.4 times as long as wide; pereonite 1 with broad anterolateral margins reaching half the length of cephalon; coxae 2–4 posteroventral margins rounded, coxae 5–7 posteroventral margins project laterally in dorsal view; pleonites subequal in length, pereonite 7 posterolateral margin extending to pleonite 4; pleotelson posterior margin rounded; uropods not extending beyond posterior margin of the pleotelson and pleopod 2 of female holotype with an appendix masculine.

Avdeev (1979a) originally described C. bychowskyi from Australia and included information on the male specimen. Avdeev (1979a) made a comparison to C. parupenei Avdeev, 1979a and also mentioned the deposition of the paratypes at TINRO ( AGK 75012–75021). Cymothoa bychowskyi is currently known to parasitise only the red cornetfish, Fistularia petimba and occurs in a small geographical range. This species has only been collected least and would require more collections for a more informative analysis.

Cymothoa bychowskyi has high host specificity and the infrequent reports would suggest low occurrence. Rameshkumar et al. (2013) reported 7.9% prevalence (3 of 38 hosts) of the species from Agatti Island, Lakshadweep, southeastern India.

Distribution. Northwestern and Western Australia, precise locality not given ( Avdeev 1979a; Kensley 2001). Also reported from Guam, Micronesia ( Williams et al. 2000), Okinawa, Japan ( Williams et al. 2000), Lakshadweep and India ( Rameshkumar et al. 2013).

Hosts. Known only from family Fistulariidae : Fistularia petimba, Lacepède, 1803 , (see Avdeev 1979a; Williams et al. 2000; Rameshkumar et al. 2013d) and bluespotted cornetfish Fistularia commersonii Rüppell, 1838 ( Williams et al. 2000).

Figures

FIGURE 1. a–c, Anilocra dimidiata Bleeker, 1857, female (24 mm), (ZSI/MBRC D1-529); d–f, Catoessa boscii (Bleeker, 1857), female (17 mm), (ZSI/MBRC D1-530); g–i, Ceratothoa angulata (Richardson, 1910), female (29 mm), (ZSI/MBRC D1-533); j–l, Cymothoa bychowskyi Avdeev, 1979, female (27 mm), (CAS/MBRM C-87); m–o, Cymothoa eremita (Brünnich, 1783), female (29 mm), (ZSI/MBRC D1-532); p–r, Cymothoa frontalis Milne Edwards, 1840, female (25 mm), (CAS/MBRM C-89).