Erylus trisphaerus (de Laubenfels, 1953)

Fig. 41

Diagnostic features.

Massive amorphous to lobate, dark to paler brown. The surface is smooth with very small pores. Oscula on top of lobes, ≤ 1 cm wide, with a very thin brown membrane. Compressible and dense in consistency.

Similar species.

The peanut-shaped aspidasters, with two to three swollen areas, allows its distinction from co-occurring species of the genus.

Distribution and abundance.

This is a rare species originally described from Apalachee Bay in north Florida at 13 m deep. Since then, it has been reported from shallow reefs in Alacranes Reef (Southern GOM), Cuba, and Curacao. This is the first report from mesophotic reefs and first report from northwestern GOM at FGBNMS where it occurs with rare to low abundance (1-10) at six sites.

Ecology.

Coralline algal reefs, algal nodules, lower mesophotic reefs.

Identification.

KR, CA, SWK, MCD.

Reference.

Ugalde et al. 2015.