Mucrospirifer
| Mucrospirifer Temporal range:    | |
|---|---|
| Mucrospirifer mucronatus | |
| Scientific classification  | |
| Kingdom: | Animalia | 
| Phylum: | Brachiopoda | 
| Class: | Rhynchonellata | 
| Order: | †Spiriferida | 
| Suborder: | †Delthyridina | 
| Superfamily: | †Delthyridoidea | 
| Family: | †Mucrospiriferidae | 
| Genus: | † Grabau, 1931  | 
| Type species | |
| Delthyris mucronatus Conrad, 1841   | |
| Species | |
|   See text  | |
Mucrospirifer is a genus of extinct brachiopods in the class Rhynchonellata (Articulata) and the order Spiriferida. They are sometimes known as "butterfly shells".[2] Like other brachiopods, they were filter feeders. These fossils occur mainly in Middle Devonian strata[2] and appear to occur around the world, except in Australia and Antarctica.[1][3]
The biconvex shell was typically 2.5 cm long,[2] but sometimes grew to 4 cm. The shell of Mucrospirifer has a fold, sulcus and costae. It is greatly elongated along the hinge line, which extends outward to form sharp points.[2] This gives them a fin- or wing-like appearance. The apex area (umbo) of the pedicle valve contains a small fold for the pedicle.[2] Mucrospirifer lived in muddy marine sediments, and were attached to the sea floor via the pedicle. The shell sometimes looks like two seashells stuck together.
Species

- Mucrospirifer albanensis
 - Mucrospirifer arkonensis
 - Mucrospirifer bouchardi
 - Mucrospirifer diluvianoides
 - Mucrospirifer grabaui
 - Mucrospirifer medfordsis
 - Mucrospirifer mucronatus (Conrad, 1841)
 - Mucrospirifer paradoxiformis
 - Mucrospirifer profundus
 - Mucrospirifer prolificus
 - Mucrospirifer refugiensis
 - Mucrospirifer thedfordensis
 - Mucrospirifer williamsi
 
References
External links
- Color reconstruction of Mucrospirifer arkonensis at www.emilydamstra.com