Cidaris schweinfurthi Gauthier, 1901

Mohamed Abdelhamid, Marouf Abdel-Aty & Moustafa Azab, Mahmoud, 2012, Turonian-Santonian echinoids from Egypt, Geodiversitas 34 (3), pp. 575-615 : 580-582

Cidaris schweinfurthi Gauthier, 1901 ( Fig. 5D)

Cidaris schweinfurthi Gauthier in Fourtau, 1901: 55, pl. 1, figs 1-3.

Dorocidaris schweinfurthi – Fourtau 1914: 1, pl.1, fig. 1.

Desoricidaris schweinfurthi – Geys 1992: 141, 143.

MATERIAL EXAMINED. — Numerous test fragments and radioles from the Coniacian-Santonian of Abu Roash (Ostrea and Plicatula unit), ASUARE6-7, Abu Roash echinoid horizon 4 ( REH 4).

DESCRIPTION

Ambulacra slightly flexuous. Pores in the pore pair separated by a granulated ridge.Pore pairs separated by horizontal linear groove. Interporiferous zone occupied by four to six horizontal granules. Areole deep, round, nonconfluent. Adradial extrascrobicular

FIG 4. — Stratigraphic section of the Turonian-Santonian sequence in Wadi Abu Qaada (Wata and Matulla formations) showing the distribution of the echinoid species and echinoid horizons. Symbols of lithology: see Figure 3.

surface narrow. Interradial extrascrobicular surface wide and occupied by numerous horizontal series of granules separated by linear grooves. Radioles incomplete; shaft cylindrical, ornamented by axial rows of small nodes.

REMARKS

This species is distinguished from D. aegyptica by the presence of sex rows of granules on interporiferous zone at ambitus, deeper areoles, wide extrascrobicular area, and by non-conjugate pores in the pore pair. It is distinguished from D. crameri by the difference in number of rows of granules in interporiferous zone (ten rows of granules at ambitus of D. crameri ), round areoles, non-conjugate pores, and by the shape of radioles. Geys (1992) referred the present species to Desoricidaris (with conjugate pores) in spite of it has non-conjugate pores (according to Fourtau (1914), and the present material).