Ophionereis annulata (Le Conte 1851)

Disk rounded (dd = 2.8 to 14.3 mm) and covered by small and imbricating scales. Central primary plate evident. Radial shields small, triangular and surrounded by large disk scales (Fig. 4J). Ventral interradius covered by imbricating scales, which are smaller than dorsal scales. Bursal slits large and with small genital papillae (Fig. 4K). Oral shields diamond-shape, longer than wide. The madreporite is evident. Adoral shields lanceolate, not meeting within. Four rounded and spaced oral papillae on each side of jaw. Single enlarged, triangular papillae found distally (Fig. 4L). Dorsal arm plates longer than wide. Accessory dorsal arm plates well developed (Fig. 4H). Ventral arm plates slightly longer than wide. Three arm spines with blunt tips. A single, flat and oval tentacle scale completely covering each tentacle pore (Fig. 4I). Disk light brown with closely spaced brown-purplish rounded spots. Arms with dark dorsal plates every fourth or fifth plate (Fig. 4G).

USA (California), Mexico, El Salvador, Costa Rica, Panama, Colombia, Ecuador and Galapagos Islands (Verrill 1867, Campbell 1921, Nielsen 1932, Ziesenhenne 1937, 1940, Neira and Cantera 2005, Honey-Escandón et al. 2008, Alvarado et al. 2010). In Mexico, from the Gulf of California (Baja California Sur, Sonora, Sinaloa), Nayarit, Jalisco, Revillagigedo Islands, Colima, Michoacán, Guerrero and Oaxaca (Solís-Marín et al. 2005, Honey-Escandón et al. 2008, Granja-Fernández et al. 2013). From 0 to 229 m depth (Maluf 1988). In this study, Ophionereis annulata was collected on coral reefs from Jalisco, Colima, Michoacán, Guerrero and Oaxaca, from 3.6 to 13.5 m depth.