''Frenguelliceras'' is an

ammonite 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) ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

from the

Lower Cretaceous Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Lower Wick is a small hamlet located in the county of Gloucestershire, England. It is situated about five miles south west of Dursley, eight ...

included in the perisphinctoid family

Neocomitidae Neocomitidae is a family of Lower Cretaceous ammonitids comprising genera with strongly ribbed evolute (all whorls exposed) to smooth, fairly involute (inner whorls mostly hidden) shells. In the 1957 description of the family Neocomitidae was r ...

named by Leanza in 1945. The type species, ''F. magister'', is from the

Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretaceou ...

,(Lower Cretaceous), of Argentina. ''Frenguelliceras'' has an evolute, flat sided shell with coarse, simple or widely splayed ribs dividing from the umbilical edge -inner margin of the outer whorl; venter -outer rim- with a smooth groove, bordered by incipiently tuberculate rib endings.

References

* W.J. Arkell, et al., 1957. Mesozoic Ammonoidea,

Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and co ...

Part L, Ammonoidea
Frenguelliceras-Paleodb
Ammonitida genera Perisphinctoidea Early Cretaceous ammonites Fossils of Argentina Valanginian life {{Ammonitina-stub