Scientific name Tentaculites Higher classification Tentaculitidae Order Tentaculitida | Family †Tentaculitidae Phylum Mollusca (?) Rank Genus | |
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Similar Molluscs, Cornulites, Microconchida, Conchicolites, Chonetes | ||
Tentaculites is an extinct genus of conical fossils of uncertain affinity, class Tentaculita, although it is not the only member of the class. It is known from Lower Ordovician to Upper Devonian deposits both as calcitic shells with a brachiopod-like microstructure and carbonaceous 'linings'. The "tentaculites" (i.e. tentaculita) are also referred to as the styliolinids.
Contents
Affinity
The taxonomic classification of tentaculitids is uncertain, but some group them with pteropods. They may also be related to other conical shells of uncertain affinity including cornulitids, Anticalyptraea, microconchids and trypanoporids. Their shell microstructure has warranted their comparison with the brachiopods and phoronids.
Morphology
Tentaculitids have ribbed, cone-shaped shells which range in length from 5 to 20 mm. Some species septate; their embryonic shell, which is retained, forms a small, sometimes spherical, chamber.
Ecology
Some species are inferred to have been planktonic.
