Agelas dilatata (Duchassaing & Michelotti, 1864)

Fig. 5

Diagnostic features.

Flabellate to fan- and cup-shaped, <3 cm thick, sometimes pedunculated. Brown in color. The surface is smooth with abundant and homogeneously arranged round oscula (4-10 mm) on the upper side, and small unevenly dispersed ostia (1-2 mm wide) on the underside.

Similar species.

Agelas dispar, a fan-shaped brown species, which is thicker and possesses mostly key-holed oscula.

Distribution and abundance.

Previously considered restricted to the Bahamian-Greater Antilles shallow coral reefs (18-30 m deep) and Cuba (90-115 m). This is the first report for the NW GOM, where it is rare at Sonnier Bank.

Ecology.

Coralline algae reefs. Specimen is overgrown by a film of green algae. A unique alkaloid isolated from a Yucatan specimen is bioactive against a multidrug-resistant pathogen Pseudomonas aeruginosa (Pech-Puch et al. 2020).

Identification.

MCD.

References.

Díaz et al. 2019; Parra-Velandia et al. 2014.