Ceramaster grenadensis ( Perrier, 1881 )

Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, Zootaxa 4766 (2), pp. 201-260 : 216-217

Ceramaster grenadensis ( Perrier, 1881)

Figures 6 B–D

This species was identified based on the abactinal tabulae on the surface as well as the darkened central surface regions on the superomarginal plates which broadly corresponds to the morphological definition of Ceramaster grenadensis from this region. This is a widely occurring species [ Clark and Downey (1992)] and shows variable characters, including marginal plate number, decoration and shape, body form as well as abactinal and furrow spination. Clark and Downey (1992) argue for species, such as Ceramaster patagonicus as a subspecies of Ceramaster grenadensis . Their determination has not been widely accepted (e.g., Mah 2011).

Feeding Observations

The first Richardson Scarp observation at 954 m shows an individual hunched over dead coral rubble, likely feeding on the brown epizoic organisms on the surface. The second Richardson Scarp observation at 897 m shows an individual with two possible sponge stalks or other fragments emerging from below the oral surface.

Worm Association

One observation of this species in Okeanos Ridge at 734 m showed an individual with a yellow polynoid polychaete present on its abactinal surface.

Occurrence: Florida to Northern Brazil, Azores, Southwest Ireland to the Gulf of Guinea, the Mediterranean. 200– 2500 m.

Images Examined

with worm. Okeanos Ridge , 25.67993, -84.62042, 734 m

EX1711_IMG_20171202T143855Z_ROVHD.jpg

feeding-coral skeleton. Richardson Scarp, North Atlantic. 32.09334, -77.16114, 954 m EX1806_IMG_20180622T153725Z_ROVHD.jpg

Richardson Scarp, North Atlantic. 32.09346, -77.16175, 897 m EX1806_IMG_20180622T172206Z_ROVHD.jpg

Figures

FIGURE 6. Unidentified species and Ceramaster grenadensis. A. Unidentified genus and species 1, NW Florida Escarpment, Gulf of Mexico, 2178 m. B. C. grenadensis in situ feeding. Unidentified stalks emerging from below (indicated with arrows). Richardson Scarp, North Atlantic. 897 m C. C. grenadensis feeding on coral rubble. Richardson Scarp, North Atlantic. 954 m D. C. grenadensis with yellow scale worm associate (indicated by arrow). Okeanos Ridge, 734 m.