Spirastrella vagabunda var. arabica Topsent 1893

Spirastrella vagabunda var. arabica Topsent, 1893

(Fig. 8E)

Spirastrella vagabunda var. arabica Topsent, 1893: 177, fig. 1.

The variety was described by Topsent from two localities in the Gulf of Aden, the first mentioned and illustrated was from the Gulf of Tadjoura, Banc de la Clocheterie, Djibouti approximate coordinates 11.95°N 43.3°E (syntype MNHN D.T. 1967), the second syntype was from Karaman Island, Yemen, approximate coordinates 15.3333°N 42.6167°E (no known reg.nr.). The differences noted by Topsent with the typical variety Spirastrella vagabunda Ridley (1884: 468, pl. XLIII fig. c, from Torres Strait. N Australia, 10.6°S 132.13°E, depth 7-13 m, wet syntypes BMNH 1882.23.243 and 307, fide Hooper & Wiedenmayer 1994: 375) are massive habit with ‘pyramidal’ oscula bearing lobes, which were closed in the preserved specimens. The tylostyles are thicker than those of the typical variety, and the spirasters likewise are somewhat thicker. These differences are meagre and Topsent himself was convinced that the Gulf of Aden material was not specifically different from Ridley’s types from Torres Straits. In view of the occurrence over the Indo-West Pacific of several described forms and varieties of this species which were all ultimately judged to be products of a widespread variable species, I propose to merge Topsent’s variety with the species to be named Spheciospongia vagabunda (Ridley, 1884).