Clypeaster rarispinus de Meijere, 1903

Fig. 58 A–D.

Clypeaster audouini: H.L. Clark, 1923: 392; H.L. Clark, 1924: 9 –10; H.L. Clark, 1925a: 148. Clypeaster (Leptoclypus) rarispinus: Mortensen, 1948d: 58 –62. Pl. VI, Figs 1–15. Pl. XL, Figs 4–9. Pl. LXIV, Figs 11–12, 14– 17, 20.

Clypeaster rarispinus: Clark & Courtman-Stock, 1976: 241; Schultz, 2009: 550, Figs 938–934.

Material examined. MBC-A023307; MBC-A077888; A23718; MBC-A077889; MBC-A077892; MBC- A077890; A23716; MBC-A077891.

Identification. Differs from Clypeaster species in the region in test being pentagonal, longer than wide, concave sides, posterior side convex, margin sometimes thickened; petaloid area slightly raised, petals opened; zigzag bands along food grooves. Live animal yellowish-green, oral bands along food grooves darker.

Global maximum size. Maximum test length 190 m.

Global distribution. Red Sea to East coast region of South Africa, from the Persian Gulf over the Indian Ocean to Malayan Archipelago (Schultz 2009); from littoral to 369 m

Remarks. Samples from the Iziko Museum collection demonstrate a 100 m increase from previously known maximum depth of 269 m. Differs from C. fervens in having narrow, distally opened petal.