Musculus somaliensis
Extinct species of bivalve
From Wikipedia, the free encyclopedia
Musculus somaliensis is an extinct species of small saltwater mussel, a fossil marine bivalve mollusc in the family Mytilidae, the mussels. The size, shape and sometimes color of these fossils are reminiscent of a pistachio nut.
| Musculus somaliensis Temporal range: | |
|---|---|
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| Musculus somaliensis viewed from the side | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Order: | Mytilida |
| Family: | Mytilidae |
| Genus: | Musculus |
| Species: | †M. somaliensis |
| Binomial name | |
| †Musculus somaliensis Cox, 1935 | |
| Synonyms | |
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Modiola aspera, M. autissiodorensis | |
Distribution
Musculus somaliensis lived during the late Jurassic, possibly throughout the Ethiopian Faunal Province, which consisted of Ethiopia, Somalia, Jordan, Yemen, Kenya, Madagascar, Saudi Arabia, and Tunisia according to Kiessling.[1] Fossils of M. somaliensis are known from the Upper Jurassic of Somalia (Callovian/Oxfordian in Jirba Range, Biyo Dader Tug,[2] Bihendula[3]), Ethiopia (Callovian in Mt. Guresu, Marda Pass;[4] Late Oxfordian in Antalo Limestone north of Mekele[1]) and Tunisia (Late Callovian/Oxfordian in Ghomrassen; Middle Callovian/Late Callovian in Ksar Ben Soltane, Krechem el Miit; Callovian/Early Oxfordian in Foum Tataouine Post Optique; Callovian/Oxfordian in Bir Remtha, Faljet Jdar/Ed-Dghaghra[5]).[6]
Habitat
The fossil locations cited were tropical shallow seas,[1] where this mussel lived as a stationary epifaunal suspension feeder.[6]
Description
Musculus somaliensis has a modioliform shape with a straight to weakly convex dorsal margin. A rounded carina runs from the umbo to the postero-ventral corner of the shell, forming an angle of c. 45° with the dorsal margin, ventrally followed by a shallow sulcus. The antero-ventral part of the shell is inflated and has a convex antero-ventral margin. Its carina is more strongly curved and in its distal part forms an angle of c. 60–70° with the dorsal margin. A sulcus is absent, the antero-ventral part is low and limited by a concave antero-ventral margin.[1]