* Plococidaris verticillata (Lamarck, 1816)

Fig. 15 A–C.

Phyllacanthus verticillata: A. Agassiz, 1881: 40 .

Plococidaris verticillata: Mortensen, 1928a: 428 –433. Pl. LI, Figs 3–7. Pl. LXXIV, Fig. 5. Pl. LXXXIII, Figs 19–21; Schultz, 2010: 50, Figs 88–92; Filander & Griffiths, 2014: 51. Pl. I, Fig. F.

Prionocidaris verticillata: H.L. Clark, 1925a: 17; Richmond, 1997: 294; Samyn, 2003: 200, Figs 2 E, E’.

Material examined. SAMC-A28236.

Identification. Test robust, low and flattened above and below, with arched sides; pores not distinctively conjugate. Apical disc star-shaped, dark, ocular and genital plates with a series of tubercles along the outer and inner edge. Peristome conically raised. Primary spines with three to four crown-like structures, with sharp ends; scrobicular spines adpressed. Generally green/brownish in color, primary spines somewhat banded, whorls having white tips; secondary spines greenish with a light brown base.

Global maximum size. Maximum test diameter 40 mm.

Global distribution. Kenya (Samyn 2003), Zanzibar, East coast of South Africa (Filander & Griffiths 2014), East Africa to Fiji and Hawaiian Islands, from southern Japan to Australian east coast; from littoral to 50 m (Schultz 2010).

Remarks. Distinguishable from Acanthocidaris maculicollis by its stout spines, bearing 3–4 crown structures, and its conically raised peristome.