Mucrospirifer mucronatus

Mucrospirifer mucronatus is a species of articulate brachiopod from the middle Devonian.^[1] The species serves as an index fossil for the middle Devonian.^{[2] [3]}

Mucrospirifer mucronatus Temporal range: Middle Devonian PreꞒ Ꞓ O S D C P T J K Pg N
A Mucrospirifer mucronatus from the Windom shale.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Brachiopoda
Class:	Rhynchonellata
Order:	†Spiriferida
Family:	†Mucrospiriferidae
Genus:	†Mucrospirifer
Species:	†M. mucronatus
Binomial name
†Mucrospirifer mucronatus Conrad, 1841

Discovery and history

Mucrospirifer mucronatus was discovered by Timothy Abbott Conrad in 1841 as Delthyris mucronatus. Until 1931, most species in the genus Mucrospirifer would be classified under the genus Spirifer. Amadeus William Grabau would first propose the genus Mucrospirifer in 1931, using Mucrospirifer mucronatus as the type species.

Description

Mucrospirifer mucronatus typically has a biconvex shell. The shell is covered in ribs (known as costae). The cardinal extremities on the posterior are elongated in adolescent specimens to form spines.^[4]

Morphology of Mucrospirifer

Life habits and paleoecology

Mucrospirifer mucronatus was a filter feeder, that lived anchored to the seafloor. The species would’ve been common to reefs in the middle Devonian, was attached to the seafloor through a pedicle. Mucrospirifer mucronatus would often be a host for epibionts. Like modern brachiopods, Mucrospirifer mucronatus would have tolerated relatively anoxic conditions.^[5][6]

References

1. Jackson, Paula. "Environmental and physiological influences on isotopic and elemental compositions of brachiopod shell calcite: Implications for the isotopic evolution of Paleozoic oceans" (PDF).
2. Tillman, John R. (1964). "Variation in Species of Mucrospirifer from Middle Devonian Rocks of Michigan, Ontario, and Ohio". Journal of Paleontology. 38 (5): 952–964. ISSN 0022-3360. JSTOR 1301615.
3. Welch. "Geographical Variation and Evolution in the Middle Devonian Brachiopod, MUCROSPIRIFER" (PDF).
4. Welch. "Geographical Variation and Evolution in the Middle Devonian Brachiopod, MUCROSPIRIFER" (PDF).
5. BORDEAUX and BRETT. "SUBSTRATE SPECIFIC ASSOCIATIONS OF EPIBIONTS ON MIDDLE DEVONIAN BRACHIOPODS: IMPLICATIONS FOR PALEOECOLOGY" (PDF).
6. Browser. "Faunal Assemblages in the Lower Hamilton Group in Onondaga County, New York" (PDF).