The species of Pseudaphya (Teleostei: Gobiidae) and the evolution of aphyiine gobies

The Mediterranean gobiid genus Pseudaphya Iljin, 1930, formerly containing two nominal species, the type Ps. ferreri (O. De Buen & Page, 1908) and Ps. pelagica De Buen, 1931, is now believed to be monotypic after examination of Adriatic material originally identified as Gobius pusillus Canestrini, 1861. The last is here provisionally regarded as Pomato-schistus knerii (Steindachner, 1861). The genus Pseudaphya is redefined, with additional osteological features, and its single species, Ps. ferreri , redescribed. In comparison with other small transparent gobiids, Pseudaphya is shown to possess certain primitive features and a possible mode of evolution for this group of tiny gobies by neoteny from postlarvae of hill-stream sicydiines is discussed. An origin from less specialized gobiines seems more acceptable.