Middle Ordovician – Devonian
Deceptrix is an extinct genus of facultatively mobile infaunal deposit feeders
Identification in Hand Sample:
Pojeta, Jr. & Runnegar (1985):
- Pojetaia has a few small teeth located between the umbos; some of these teeth may be subquadrate in cross section. These teeth are very much like the interumbonal teeth of an early Middle Ordovician (Whiterockian) species of the praenuculid Deceptrix, which has a full taxodont hinge.
Pojeta, Jr. (1971):
- Praenucula is sometimes distinguished from Deceptrix on the basis of the number and size of the teeth in the tooth rows anterior and posterior to the beaks. The teeth in each teeth row of Praenucula are of approximately the same size and number, whereas, in Deceptrix the teeth in the posterior tooth row are similar and more numerous than those in the anterior tooth row.
- 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.
- Yonge (1939) noted that in its life position in the substrate, Nucula nucleus has an anterior inhalant current and is shallowly buried with the anterior end approximately parallel to the sediment-water interface, and this end is covered with a thin veneer of sediment. It is assumed herein that Ordovician Nucula-like shells such as Deceptrix and Similodonta lived in a similar fashion.
Treatise on Invertebrate Paleontology, Part N, Mollusca 6(1 of 3) (1969):
- Like Praenucula, but posterior teeth smaller and more numerous than anterior.
- Praenucula: Posteriorly truncate, anterior and posterior teeth similar in size and number.