Eophyllites is a genus of ammonoid cephalopods from the Lower Triassic and a predecessor of genera like Monophyllites and Ussurites.
The shell of Eophyllites is evolute, discoidal; whorls compressed, deeply embracing; flanks gently convex, converging on a narrowly rounded venter. Sutures basically ceratitic; ventral lobe wide, divided by a high siphonal saddle; Lobesjagged, 1st lateral larger than the second; saddles monophyllic, smooth and rounded.
Related Palaeophyllites from the same age is ribbed on the outer flanks and lobes in the suture are more terminally digitate.