Stereocidaris squamosa Mortensen, 1928b

Filander, Zoleka & Griffiths, Charles, 2017, Illustrated guide to the echinoid (Echinodermata: Echinoidea) fauna of South Africa, Zootaxa 4296 (1), pp. 1-72 : 17-18

Stereocidaris squamosa Mortensen, 1928b

Fig. 13 A–C.

Stereocidaris squamosa Mortensen, 1928a: 245 –247. Pl. XX, Figs 4–6 , Pl. LXX, Fig. 7 . Pl. LXXX, Figs 10–16 ; Mortensen, 1928b: 70; Mortensen, 1932b: 151; Clark & Courtman-Stock, 1976: 218; Schultz, 2011: 1060, Figs 1844–1845.

Material examined. MBC-A077750.

Identification. Has a less aborally elevated test than Stereocidaris excavata , greenish apical disc ( Mortensen 1928b), and gonopores centrally positioned; primary spines with broad tips, with about 15 longitudinal ridges, yellowish, slightly tapered, dark line towards neck of spines; naked lines along test plates.

Global maximum size. Maximum test diameter 47 mm.

Global distribution. East coast region of South Africa, Tanzania, Saya da Malha Bank, at 270–374 m depth ( Mortensen 1928b; Clark & Courtman-Stock 1976).

Remarks. Differs from the two endemic species S. capensis and S. excavata in primary spines and genital plates, respectively. Both S. capensis and S. squamous have slightly elevated genital plates with distally positioned gonopores, but differ in the number of longitudinal ridges on the spine; the latter having about 15 and the former 12 ridges. Differs from S. excavata in raised greenish apical disc, S. excavata having a sunken one.

Figures

FIGURE 4. Tubercle types: A. perforated and non-crenulated (Stereocidaris alcocki). B. non-perforated and non-crenulated (Stomopneustes variolaris). C. perforated and crenulated (Chaetodiadema africanum).

FIGURE 5. Histocidaris elegans (SAMC-A 22212): A. Side view of preserved specimen. B. Apical system of preserved specimen.

FIGURE 6. Eucidaris metularia (SAMC-A 28226): A. Map showing distribution. B. Side view of preserved specimen. C. Apical system of preserved specimen.

FIGURE 7. Kionocidaris striata (MBC-A 022213): A. Map showing distribution. B. Apical system of preserved specimen.

FIGURE 10. Stereocidaris alcocki (SAMC-A 28229): A. Map showing distribution. B. Side view (close-up) of preserved specimen. C. Apical system of preserved specimen.

FIGURE 11. Stereocidaris capensis (MB-A 077743): A. Map showing distribution. B. Side view of preserved specimen. C. Close-up apical system of preserved specimen.

FIGURE 12. Stereocidaris excavata (SAMC-A 23320). A. Map showing distribution. B. Side view of preserved specimen. C. Close-up apical system of preserved specimen.

FIGURE 13. Stereocidaris squamosa (MBC-A 077750). A. Map showing distribution. B. Side view of preserved specimen. C. Close-up apical system of preserved specimen.

FIGURE 14. Acanthocidaris maculicollis (SAMC- A 28233). A. Map showing distribution. B. Spine close-up view of preserved specimen.

FIGURE 15. Plococdaris verticillata (SAMC-A 28236). A. Map showing distribution. B. Side view of preserved specimen. C. Apical system of preserved specimen.

FIGURE 16. Prionocidaris pistillaris. A. Map showing distribution. B. Side view of adult preserved specimen (SAMC- A 23724). C. Side view of juvenile preserved specimen (MBC-A 077755).