Phyllacanthus imperialis ( Lamarck, 1816 )

Filander, Zoleka & Griffiths, Charles, 2017, Illustrated guide to the echinoid (Echinodermata: Echinoidea) fauna of South Africa, Zootaxa 4296 (1), pp. 1-72 : 14

* Phyllacanthus imperialis ( Lamarck, 1816)

Fig. 8 A–B.

Phyllacanthus fustigera: A. Agassiz, 1863: 17 .

Phyllacanthus imperialis: A. Agassiz, 1872: 151 , 391. Pl. I, Figs 1–6 , Pl. I, Fig. 2 ; Döderlein, 1906: 98. Pl. XL, Fig. 5 . a–e; Mortensen, 1928a: 504 –509. Pl. LIV, Fig. 4 , Pl. LVII, Fig. 3 , Pl. LXXIV, Fig. 6 , Pl. LXXXVIII, Figs 4–10 ; H.L. Clark, 1925a: 10; Samyn, 2003: 197, Fig. 2 B, B’; Schultz, 2010: 46, Figs 80–83; Filander & Griffiths, 2014: 50. Pl. I, Fig. B.

Material examined. A28211 ; A23447.

Identification. Test compact, with non-crenulated primary tubercles. Apical disc sunken, small, closely tuberculated, with ocular plates widely exsert, madreporite larger than other genital plates. Peristome larger than apical disc. Primary spines dark brown, granulated with longitudinal ridged tips; secondary spines lighter brown, strongly adpressed, smooth and somewhat fusiform.

Global maximum size. Maximum test diameter 80 mm.

Global distribution. Red Sea and Madagascar to Tonga Islands, from Rui-Kui Islands to Australia; at depth 5–70 m ( Mortensen 1928a; Schultz 2010). East coast region of South Africa ( Filander & Griffiths 2014).

Remarks. Differs from Eucidaris metularia in spine characteristics, Phyllacanthus imperialis having long primaries, whereas E. metularia has short, stout ones.

Figures

FIGURE 1. Detail of regular echinoid: upper (Stomopneustes variolaris) and lower (Stereocidaris excavata) side, showing terminology of various body parts.

FIGURE 2. Body plan of an irregular echinoid or sand dollar (Clypeaster rarispinus), showing terminology of various body parts.

FIGURE 3. The body plan of an irregular echinoids or heart urchin (Echinocardium cordatum), showing terminology of different body parts.

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 8. Phyllacanthus imperialis (SAMC-A 23447): A. Map showing distribution. B. Aboral view of preserved specimen.