The earliest pterosaurs are known from Late Triassic sediments. The most notable species is Eudimorphodon from the Norian Sediments of the Zorzino Limestone (Calcare di Zorzino). This pterosaur has a distinct tooth with multiple cusps.
Above are illustrations of the teeth of Eudimorphodon ranzii. This pterosaur has a range of different sized teeth in its jaw, but most of the smaller teeth are of the form shown. Isolated teeth are extremely rare for this type of pterosaur.
Zambelli R., 1973, Eudimorphodon Ranzii gen.nov.,sp.nov. Uno Pterosauro Triassico, Rendiconti Instituto Lombardo Accademia, (rend.sc.) Pt.107 pp.27-32
Dalla Vecchia F.M., 1995, A new pterosaur (Reptilia, Pterosauria) from the Norian (Late Triassic) of Friuli (Northeastern Italy). Preliminary note. Gortania - Atti Mus. Friul. St.Nat., 16(1994): 59-66, Udine.
Dalla Vecchia F.M. and Kellner A.W.A., 1995, Comments on the pterosaurs from the Late Triassic (middle Norian) of Friuli, Northeastern Italy. Journ. Vert. Paleont., Abstract of papers, 55th Annual Meeting Society of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, 25A, Lawrence.
Dalla Vecchia F. M., 2004, A review of the Triassic pterosaur record: In: Atti del Workshop Eudimorphodon: 30th from Discovery, Museo Civico di Scienze Naturali "e. Caffi" Di Bergamo, edited by Renesto S., Rivista del Museo Civico di Scienze Naturali "Enrico Caffi", vol.22, p.13-29