Cymothoa rotundifrons Haller, 1880

Cymothoa rotundifrons Haller, 1880: 375 –377, pl. XVIII, figs. 1–4; Nierstrasz, 1931: 136; Trilles, 1994: 137; Kensley, 2001: 233 [nomen dubium].

Remarks. Trilles (1975; 1994) suggested that Cymothoa rotundifrons could be placed in synonymy with C. borbonica as C. rotundifrons is known only from the original record (from Mauritius) and corresponds with the distribution of C. borbonica . Deposition of the type material for C. rotundifrons is not known, and equally could not be located in any European museum. This species has only been collected once and with no other material to represent the species, discussions on this species are based on the type drawings. Comparison of Haller’s (1880) figures to the lectotype of C. borbonica show the two species are similar, but cannot be conclusively considered the same species, as the type material for C. rotundifrons is most probably destroyed, lost or otherwise misplaced. As the host identity for C. rotundifrons is not known and there are multiple species of Cymothoa in the Mauritius region, it is unlikely that the identity of this species will ever be established; therefore we here place Cymothoa rotundifrons into nomen dubium.