Topsentia pachastrelloides var. microxata Topsent, 1928

Topsentia pachastrelloides var. microxata Topsent, 1928: 165 (no illustration).

The variety was described by Topsent from Prince Albert 1 er Monaco Cruises Stat. 899, Azores, 37.95°N 29.233°W, depth 200 m (type material in the MOM and slides in MNHN). Differences with the typical variety described by Topsent (1892a: 66, pl. IX fig. 3, as Halichondria, from Prince Albert 1 er Monaco Cruises Stat. 229, Azores, 38.6667°N 30.5775°W, depth 736 m, type material in MOM and slides in MNHN) are the small size of the smallest oxeas (40–55 vs. 150 µm). Large oxeas are smaller (up to 960 x 25 vs.1400 x 46 µm) than those of the typical variety. These differences may seem sufficient for distinguishing valid taxa, but additional records by other authors and Topsent himself, e.g. Topsent (1928: 163) mention specimens with the smallest oxeas up to 90 µm and the largest up to 1005 x 40–50 µm. He also discussed specimens identified as Topsentia glabra (Topsent, 1898: 234 as Anisoxya), which he observed to overlap in spicule sizes with smaller spicule bearing T. pachastrelloides. In view of the uncertainties admitted by Topsent, and the sympatric occurrence of the varieties I propose to merge these varieties as a single species Topsentia pachastrelloides (Topsent, 1892a) until improved evidence has been obtained for a specific distinctness of the varieties.