''Acrochordiceras'' is a genus of
Middle Triassic ammonoid
Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...
cephalopods belonging to the
ceratitid
Ceratitida is an order that contains almost all ammonoid cephalopod genera from the Triassic as well as ancestral forms from the Upper Permian, the exception being the phylloceratids which gave rise to the great diversity of post Triassic ammoni ...
family Acrochordiceratidae, included in the superfamily
Ceratitoidea.
The shell of ''Acrochordiceras'', as with the family, is more or less involute with strong, almost transverse, ribs that cross the arched venter uninterrupted. The ventral lobe is bifid. The first lateral lobe is larger than the other and is multi-pronged. Prongs on subsequent smaller lobes are less developed and saddles are small and rounded.
''Acrochordiceras'' was described by Hyatt in 1877 and is known from
Eurasia,
Timur,
California and
Nevada.
References
* Arkell, ''et al''., 1957. Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L, Ammonoidea. Geol. Soc. of America and Univ. Kans. Press.
Ceratitoidea
Ceratitida genera
Fossil taxa described in 1877
Triassic ammonites of North America
Middle Triassic life
Middle Triassic genus first appearances
Middle Triassic genus extinctions
{{Ceratitida-stub