Cyrtospirifer

Cyrtospirifer verneuili Temporal range: Upper Givetian - Lower Famennian PreЄ Є O S D C P T J K Pg N
Cyrtospirifer verneuili from Namur (Belgium), Upper Devonian
Scientific classification
Kingdom:	Animalia
Phylum:	Brachiopoda
Class:	Rhynchonellata
Order:	Spiriferida
Family:	Cyrtospiriferidae
Genus:	Cyrtospirifer Nalivkin, 1924
species
C. verneuili (Murchison), 1840 (type) = Spirifer verneuili, S. lonsdalii C. archiaci (Murchison, 1840) C. chemungensis (Conrad, 1842) = Delthyris chemungensis, C. altiplicus C. conoideus (Roemer, 1843) C. disjunctus (Sowerby,1840) C. inermis (Hall, 1843) = Delthyris inermis C. hornellensis Greiner, 1957 C. kharaulakhensis Fredericks, 1919 C. loonesi Brice, 2002 C. mylaensis Sokiran, 2006 C. placitus Stainbrook, 1945 C. preshoensis Greiner, 1957 C. rudkinensis Sokiran, 2006 C. schelonicus Nalivkin, 1941 C. syringothyriformis (Paeckelmann, 1942) C. tenticulum (Verneuil, 1845) = Spirifer tenticulum C. whitneyi (Hall, 1858)

Cyrtospirifer is an extinct genus of brachiopoda. The fossils are present in the Middle and Upper Devonian.

Taxonomy

It is likely that Tenticospirifer, that itself appeared during early Givetian, includes the ancestor of Cyrtospirifer. Cyrtospirifer first occurs in western Europe in the Late Givetian. Tenticospirifer has a relatively narrow hingeline and an inflated and thick shell in common with two of the oldest species known, C. verneuiliformis and C. aperturatus. This group dominated during the late Givetian, but was replaced by other species, such as C. syringothyriformis and C. verneuili which have wide hingelines and thinner shells.^[1]

Description

Cyrtospirifer has a medium to large sized shell, wider than long.

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  Cyrtospirifer verneuili, 24mm long and about 60mm wide, brachial valve

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  pedicle valve

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  lateral

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  posterior

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  anterior

Reassigned species

• C. glaucus = Regelia glauca

References