Scenelloidea is an extinct superfamily of paleozoic
molluscs of uncertain position (
Gastropoda,
Helcionelloida
Helcionelloida is an extinct group of ancient molluscs (phylum Mollusca). These are the oldest known conchiferan molluscs, that is, they had a mineralised shell. Some members of this class were mistaken for Monoplacophorans. The class was ere ...
, or
Monoplacophora
Monoplacophora , meaning "bearing one plate", is a polyphyletic superclass of molluscs with a cap-like shell inhabiting deep sea environments . Extant representatives were not recognized as such until 1952; previously they were known only from ...
).
Families
Based on the
taxonomy of the Gastropoda by Bouchet & Rocroi (2005) families in the Scenelloidea include:
* †
Scenellidae
''Scenella'' is an extinct genus of fossil invertebrate animal which is generally considered to be a mollusc; at various times it has been suggested that this genus belongs with the gastropods, the monoplacophorans, or the helcionellids, althoug ...
* †
Coreospiridae
* †
Igarkiellidae
''Igarkiella'' is an extinct genus of trilobite containing a single described species ''Igarkiella igarkaensis''. The species is known from fossils dating to 505 to 501 million years ago during the Cambrian Period
The Cambrian Period ( ; so ...
References
* Miller, S. A. (1889). ''North American Geology and Palaeontology for the use of Amateurs, Students and Scientists''. Western Methodist Book Concern. Cincinnati. 664 p
Prehistoric gastropods
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