Carditamera affinis

Carditamera affinis
Carditamera affinis (from Reeve, 1843 (Cardita): Plate 1, Fig. 4)
Systematics
Archiheterodonta Order : Carditida Superfamily : Carditoidea Family : Trapezoidal shells (Carditidae) Genre : Carditamera Type : Carditamera affinis
Scientific name
Carditamera affinis
( GB Sowerby I , 1833)

Carditamera affinis is a shell - type from the family of trapeze shells (Carditidae). It occurs on the west coast of America from Baja California to Peru in the shallow coastal waters.

features

The same-folding case is up to 10 cm long. It is elongated-elliptical in outline, the longitude-latitude index is about 2.6. It is strongly unequal, the forward curled vertebra sits about 25% of the total length from the front end. The posterior dorsal margin is long and straight, it runs approximately parallel to the ventral margin. It merges into the rear edge at a very flat angle. The rear edge is broadly rounded or slightly truncated. The anterior dorsal margin is short and almost straight. It slopes down gently to the front edge, which is more rounded than the rear edge. The ventral margin is straight to slightly concave. The ligament lies externally behind the vertebrae. The small lunula is egg-shaped. There are two main teeth and a strong front posterior tooth in each valve. The two sphincters are approximately the same size. The surface line is entire.

The shell is thick and firm. The ornamentation consists of 12 to 15 radial ribs, which are higher and also wider in the rear part of the housing. At the front end, however, they are greatly weakened. They are crossed by irregular ribs parallel to the edge, which can be formed into scales on the rear housing part. The outside is predominantly colored light brown, at the rear end dark brown. The inner surface of the case is white with darker parts at the rear end and on the belly side, with some specimens these case parts are also completely black. The periostracum is dark brown. The edge of the case is notched.

Geographical distribution and habitat

The distribution area of Carditamera affinis extends along the Pacific coast from Baja California (about 26.2 ° N) south into the Gulf of California (there to San Felipe , about 31.0 ° N and Puerto Peñasco (state of Sonora) at 31.2 ° N). further along the Pacific coast south to Yasila , Piura ( Peru , 5.1 ° S). The species is also found in the waters around the Galapagos Islands .

The animals live in the interstices in coarse rubble, attached with byssus from the intertidal zone to a depth of around 90 meters.

Taxonomy

The species was founded in 1833 by George Brettingham Sowerby I under the original binomial Cardita affinis . Synonyms are: Cardita californica Deshayes, 1854, Cardita incerta Clessin, 1888, Cardita pectunculus Reeve, 1843, Cardita picta Clessin, 1888 and Cardita volucris Reeve, 1843.

supporting documents

literature

• Eugene Victor Coan, Paul Valentich-Scott: Bivalve Seashells of Tropical West America marine Bivalve mollusks from Baja california to Northern Perú. Part 1,598 pp., Santa Barbara Museum of Natural History, Santa Barbara 2012 ISBN 978-0-936494-43-2 (p. 385)
• Edouard Lamy: Review of the Carditacea vivants du Muséum National d'Histoire Naturelle de Paris. Journal de Conchyliologie, 66: 218–276, 289–368, 1922 Online at www.biodiversitylibrary.org (p. 257)

Individual evidence

1. ^ Lovell Augustus Reeve: Conchologia iconica, or, Illustrations of the shells of molluscous animals. Vol. 1, Reeve & Brothers, London 1843 Online at www.biodiversitylibrary.org (Plate 1).
2. ^ George Brettingham Sowerby I: Collection of shells formed by Mr. Cumings on the Western Coast of South America. Proceedings of the Committee of Science and Corresponence of the Zoological Society of London, 1832 (II): 194-202, London 1833 Online at Google Books (p. 195)
3. ↑ MolluscaBase: Carditamera affinis (GB Sowerby I, 1833)