Worthenia is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

found in the fossil record. This genus is primarily found in rocks formed during the

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

periods (416-200 Ma) from the central areas of North America. ''Worthenia'' was named for the paleontologist

Amos Henry Worthen Amos Henry Worthen (1813–1888) was an American geologist and paleontologist from Illinois. He was the second state geologist of Illinois and the first curator of the Illinois State Museum. He was a fellow of the American Association for the Ad ...

, who lived from 1813-1888. ''Worthenia'' species have a "turban-shaped shell in which a raised ridge follows the margin of the whorls. Small nodes occur along the ridge, and the opening of the shell is oval and large."Worthenia
" ''Encyclopædia Britannica''. 2010. Encyclopædia Britannica Online. 04 Nov. 2010.

References

Lophospiridae Devonian first appearances Triassic extinctions {{paleo-gastropod-stub