Ctenodonta

Classification
Phylum: Mollusca
Class: Bivalvia
Order: Nuculoida
Family: Ctenodontidae
Genus: Ctenodonta Salter, 1852
Cincinnatian Species: Ctenodonta perminuta

Taxonomic Details

Synonyms: Nucula (Tellinomya) Hall, 1847; Tellinomya Hall, 1847

Geologic Range
Middle Ordovician

Common Paleoecology
Ctenodonta is an extinct genus of facultatively mobile infaunal deposit and suspension feeders

Identification in Hand Sample:

  • Beaks near the anterior margin
  • Elongate shell
  • Lacks concentric sculpture
  • Numerous subequal teeth in the hinge

Geographic Occurrences

Species Differentiation

Published Description

Fossils of Ohio (1996):

  • Shell elongate
  • The Middle Ordovician genus Ctenodonta is represented by C. perminuta, a small ovate species that has the beaks near the anterior margin and numerous subequal teeth in the hinge.

Pojeta, Jr. & Runnegar (1985):

  • Palaeosolemya ordovicicus has a lateral profile much like that of various species of the paleotaxodont Ctenodonta, which is a widespread opisthogyrate Ordovician genus.
  • Like Palaeosolemya, Ctenodonta is higher anteriorly than posteriorly, and its dorsal and ventral margins are not subparallel.
  • Ctenodonta is characterized by typical taxodont teeth.

Pojeta, Jr. (1971):

  • Both suspension feeders (Lyrodesma) and deposit feeders (Ctenodonta) are known from the late Early Ordovician onward.
  • Ordovician nuculoids like their living counterparts were probably deposit-feeding infauna. In general, they can be divided into two groups: nuculiform shells such as Deceptrix and nuculaniform shells such as Ctenodonta.
  • The species of Lemubulus and Yoldia studied by Yonge and Stanley burrow diagonally, completely burying the shell. It seems likely that Ctenodonta lived in a manner similar to one of these genera.

Treatise on Invertebrate Paleontology, Part N, Mollusca 6(1 of 3) (1969):

  • Very large, elongate, lacking concentric sculpture

Ulrich (1893):

  • I had prepared an entire plate of species of this genus or this paper, but the lack of time required for the final study which it is my habit give to all species described by me immediately preceding the transmission of the manuscript to the print, has induced me to delay their publication to some other opportunity. The illustrations of the three species following happened to be placed on plated devoted chiefly to other shells here described, so that I could not very well postpone their consideration.
  • A full description of the genus and of numerous species will be found in the Minnesota work above cited.

C. perminuta