Echinocyamus pusillus

Habitat: lives buried in soft substrates, in sand, detritic and gravelly bottoms where it feeds on detritus and foraminifera (Koehler 1898, Picton 1993). Larval stage: planktotrophic (Mortensen 1927 a).

Sumber: The Echinoderm Fauna of the Azores (NE Atlantic Ocean)

(Fig. 32) Reports for the Azores:

Sumber: The Echinoderm Fauna of the Azores (NE Atlantic Ocean)

Description: test small, flattened, variable in form; outline generally elongated oval, though among the smallest specimens frequently ellipsoid (width = 66 – 74 % TL; TL <3 mm) becoming more circular or subpentagonal in larger individuals (width = 100 % TL; TL Ξ 7 mm). Apical disc central to slightly posterior, with large genital pores and five small ocular pores. The lower half of the apical side locally depressed in larger individuals (TL = 7 – 8 mm). Oral area mostly flat; depression between the peristome and periproct particularly evident in the larger specimens (TL> 5 mm). Peristome circular to subpentangular, relatively concave; diameter of the peristome about 30 – 33 % TL in smaller individuals (TL <3 mm) decreasing to 13 – 19 % TL in larger specimens (TL Ξ 7 mm). Periproct ellipsoid to round, small (6 – 12 % TL) lies halfway between the peristome and the posterior margin. Petals well developed, but not reaching the edge of the test; pore-series almost parallel, open distally, reaching ten pore pairs per column in the posterior ambulacra in the largest specimens (TL = 7 – 8 mm). Spines short, relatively uniform. Colour (in ethanol): test and spines white or cream, occasionally green.