William Swainson

“ There is no striking difference between this and A. Tobianus, excepting the extraordinary shape of the dorsal fin, which is invariably undulated and narrowed in the middle. It never grows to a size exceeding the figure, and is usually much less; while the British species is often found double the length. Like that, also, A. Siculus has the lateral line running close to the dorsal fin ”

“ Corpus gracile, teretiusculum, polyedrum, elongatum, squamis vix conspicuis. Labium superius duplicatum; mandibula inferior angusta, acuminata. Membrana branchiostega septem-radiata. Pinna dorsalis corpore penè æqualis, radiis simplicibus flexilibus. ”