Echinostrephus molaris (Blainville, 1825)

Fig. 49 A–B.

Echinostrephus molare: Alcock & Anderson, 1894: 193; Döderlein, 1910: 248; H.L. Clark, 1923: 387 –388; H.L. Clark, 1925a: 130.

Echinostrephus molaris: Mortensen, 1943: 311 –316. Pl. XXXV, Figs 1–10. Pl. LVIII, Figs I, 2, 4, 9; Clark & Courtman-Stock, 1976: 239; Richmond, 1997: 298; Samyn, 2003: 205, Fig. 3 F; Branch et al., 2010: 236, Fig. 106.2; Schultz, 2010: 207, Figs 385–389.

Material examined. MBC-A 022256; MBC-A077882; MBC-A023312.

Identification. Test small, flattened aborally and orally, upper-side broader. Spines cylindrical, needle-shaped, longest on aboral side. Denuded test light green, sometimes with purplish tint, apical plates darker, white around mouth; spines dark purple, white around mouth.

Global maximum size. Maximum test diameter 23 mm.

Global distribution. Red Sea and East coast of Africa southward to South Africa, from Bonin Islands to Australia and Fiji Islands; from littoral zone to 50 m (Schultz 2010).

Remarks. Distinguished from Echinometra species by test shape and spine size. E. oblonga has a more ovate test and the stout, short spines projecting sideways; on the other hand E. molaris has a circular test with slender, cylindrical spines projecting vertically.