Pseudoceros bolool Newman & Cannon 1994

Pseudoceros bolool Newman & Cannon, 1994 Fig. 10 Material examined. Campeche coast, Mexico • 1; Cayo Arcas; 20.2°N, 92.0°W; 3.2 m; 24 Apr. 2018; A. Hernández leg.; CRPPY -0079. Distribution. Recorded in Heron Island and One Tree Island, Australia; Madang, Papua New Guinea (Newman and Cannon 1994); Shivrajpur, Gujarat (Thakkar et al. 2017); Andaman and Nicobar Island, India (Sreeraj and Raghunathan 2015); Caribbean Sea and Florida (Rawlinson 2008). This is the first record for the Campeche coast. New record for the Gulf of Mexico. Description. Body shape elongated with rounded anterior margin, tapering posteriorly, 3.5 cm in length and 1 cm in width. Margins slightly wavy. Ground colour velvety black, without any specific additional pattern, but with a small stain, devoid of pigment, present in area of cerebral eyes (Fig. 10 A, B). Greyish ventrally. A characteristic bulge marks main intestinal trunk in body midline (Fig. 10 C). Pseudotentacles simple folds of anterior margin. Cluster of cerebral eyes horseshoe-shaped at anterior end (Fig. 10 A). Remarks. Within Pseudoceros, P. bolool and P. velutinus (Blanchard, 1847) share several external and internal morphological characters, characterised by a uniform velvety black coloration, without spots, bands, or marginal lines. While both species share several external and internal morphological traits, they can be distinguished by the ventral coloration: P. velutinus has a bluish violet background whereas P. bolool is grey, and by their marginal folds, which are broader in P. velutinus and more subtly defined in P. bolool. The specimen found in the Gulf of Mexico matches the original description of P. bolool. This species has been previously reported from the Australasian region (Newman and Cannon 1994, 1998) and the Indomalayan region (Dixit et al. 2021). Prior to this study, P. bolool was cited in Florida by Rawlinson (2008).