Aplococeratidae is a family of
ceratitids from the
Middle Triassic
In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between Ma and ...
with very simplified sutures and a tendency to lose their ornamentation. Shells are generally evolute, more or less compressed, with rounded venters. Ornamentation if present consists of umbilical ribs that disappear outwardly, toward the venter. The suture is ceratitic or goniatitic.
Arkell ''et al.'' (1957), in the
Treatise on Invertebrate Paleontology, Part L included the Aplococeraitdae in the
Ceratitaceae
Ceratitoidea, formerly Ceratitaceae, is an ammonite superfamily in order Ceratitida characterized in general by highly ornamented or tuberculate shells with ceratitic sutures that may become goniatitic or ammonitic in some offshoots. (Arkell ' ...
, whereas E. T. Tozer in 1981 includes them in the
Danubitaceae
The Danubitoidea is a large and diverse superfamily in the order Ceratitida of the Ammonoidea that combines five families removed from the Ceratitaceae, Clydonitaceae, and Ptychitaceae.
Taxonomy
Superfamily Danubitoidea
* Family Aplococeratidae
...
, established by Spath, also in 1951.
Genera included in the Aplococeratidae are ''
Aplococeras'' (type), ''
Apleuroceras'', ''
Epiceratites'', ''
Laboceras'', ''
Metadinarites'', ''
Pseudaplococeras'', and ''
Velebites''.
References
Sources
*Arkell, ''et al'', 1957. Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L (''L''157-158). Geological Society of America and University of Kansas Press.
Paleobiology Database Aplococeratidae entryaccessed 9 December 2011
Danubitaceae
Ceratitida families
Anisian first appearances
Middle Triassic extinctions
{{Ceratitida-stub