Geodia (Isops) ovifractus var. cyathioides Burton, 1926

Van Soest, Rob W. M., 2024, Correcting sponge names: nomenclatural update of lower taxa level Porifera, Zootaxa 5398 (1), pp. 1-122 : 55

Geodia (Isops) ovifractus var. cyathioides Burton, 1926

Geodia (Isops) ovifractus var. cyathioides Burton, 1926: 18 (no illustration).

This variety was described by Burton from the coast of Natal, South Africa (no further data). The dried holotype specimen BMNH 1924.5.1.74 (with slide 1924.5.1.106), differs from the typical variety G. (I.) ovifractus Burton (1926: 17 , also from South Africa, off the Natal coast, collected by South African Marine Survey Stat. 109, 29.7367°S 31.3458°E, depth 91 m, dried syntypes BMNH 1924.5.1.45–46) only in shape: the typical variety (a photo is provided in Burton 1926: pl. 3 fig. 1) is pear-shaped with its thinnest part near the substratum. The oscules are located on the broadest upper part and are slightly raised. The var. cyathioides (not illustrated) is stated to be cup-shaped, with oscules on the inner wall of the cup, flush with the surface. Spicule complement of both varieties is stated to be the same, including peculiar centrotylote flexible microxeas (only those of the typical variety are drawn in Burton 1926: pl. 4 fig. 2).This latter feature, the fact that shapes of the two varieties are not dramatically different (a stalked ‘pear’ can be easily transformed to a shallow cup, depending on environmental circumstances), and that both are from nearby localities make it likely that the varieties are not specifically distinct. Accordingly, I propose to merge the var. cyathioides with the typical variety and consider them a single species Geodia ovifractus Burton, 1926 .