Cymothoa bychowskyi Avdeev, 1979

Martin, Melissa B., Bruce, Niel L. & Nowak, Barbara F., 2016, Review of the fish-parasitic genus Cymothoa Fabricius, 1793 (Crustacea: Isopoda: Cymothoidae) from Australia, Zootaxa 4119 (1), pp. 1-72 : 6-7

Cymothoa bychowskyi Avdeev, 1979

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, 2013: 42, fig. 1(C).

Type material. Holotype: ovig. ♀ (28 mm), off northwestern Australia, from red cornetfish Fistularia petimba Lacépède, 1803 ( TINRO АGK 75011).

Paratypes: 4 ovig. ♀ ( TINRO АPK 75012–75015), 1 non-ovig. ♀, ( TINRO АPK 75016), 4 mature ♂ ( TINRO АPK 75017–75020), 1 immature ♂ ( TINRO АPK 75021); same data as holotype.

Remarks. No material of this species was examined. A loan request for the types was made, but the specimens could not be located. 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 masculina (0.7 times as long as pleopod 2 exopod length).

Avdeev (1979a) briefly compared C. bychowskyi to C. parupenei Avdeev, 1979a . Both species have a subtruncate cephalon, and are widest at pereonite 5. Cymothoa bychowskyi is distinguished from C. parupenei by the elongate body, 2.4 times longer than wide (compared to the 1.7 longer than wide body in C. parupenei ); anterolateral margins of pereonite 1 projecting forward (compared to the broader anterolateral margins of pereonite 1 curved mesially towards cephalon), and the rounded posterior margin of pleotelson (compared to the subtruncate posterior margin of C. parupenei ).

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) and Lakshadweep, India ( Rameshkumar et al. 2013).

Hosts. Known only from family Fistulariidae : Fistularia petimba , previously Fistularia villosa Klunzinger, 1871 (see Avdeev 1979a; Williams et al. 2000; Rameshkumar et al. 2013) and bluespotted cornetfish Fistularia commersonii Rüppell, 1838 ( Williams et al. 2000) .