The Middle Jurassic sequence of the West Sicilian Monte Kumeta contains a faunal level
with a very rich Late Bathonian ammonite assemblage. The typical Tethyan fauna with
many representatives of phylloceratids and lytoceratids also yielded oppeliids, perisphinctids
and other diagnostic forms (incl. the index Prohecticoceras blanazense Elmi, 1967)
to date the assemblage as the lower, Blanazense Subzone of the Prohecticoceras retrocostatum
Zone. The probably lower position of the assemblage within the Retrocostatum Zone
precedes the general appearance of the Bathonian heteromorph genus Parapatoceras,
thus two new genera (Kumetaceras n. gen, with type species K. enigmaticum n. sp. and
Sikeliceras n. gen. with type species S. costatum n. sp.) are of special interest
from the point of view of the origin and/or dimorphism of Bathonian-Callovian heteromorphs.
Other new forms are also described: the strigoceratid Phlycticeras tenue n. sp., the
oppeliid Paroecotraustes minor n. sp. and the perisphinctid Sicilisphinctes n. gen.
(with type species S. incertus n. sp.) and Albanesiceras n. gen. (with type species
A. damianoi n. sp.). Some other, rare ammonites are described in detail, further forms
are figured and discussed shortly.
