Echinocyamus pusillus

Description. Test small and fragile test, up to 12 mm long. Genital and ocular plates fused, with four gonopores (Fig. 2 c). Ocular pores smaller than gonopores. Only one hydropore on the apical system. Petals distinct and open distally. Periproct very small, located halfway between peristome and posterior margin of test (Fig. 2 d). Oral side slightly depressed around peristome (Fig. 2 d).

Sumber: Deep-sea Echinoids from the Galician Bank (North Atlantic Ocean)

Distribution. Atlantic Ocean: south of Svalbard, Norwegian Sea, North Sea, west of Iceland, United Kingdom, English Channel, Ireland, Bay of Biscay, west and north Galicia, Azores, south of Portugal, west Africa, Mediterranean Sea (O. F. Müller, 1776; Mortensen, 1927; Schultz, 2005; Kroh, & Mooi, 2022; OBIS, 2022) Bathymetrical range. 0 m (Mortensen, 1903) – 1250 m (Mortensen, 1927). Present study: 1313 m.

Sumber: Deep-sea Echinoids from the Galician Bank (North Atlantic Ocean)

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.

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

Fossil record: also reported from the Pliocene and Pleistocene outcrops of Santa Maria Island (Madeira et al. 2011, 2017 a).

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