Mediospirifer audaculus

Table of Contents

Scientific Classification


Kingdom: Animalia
Phylum: Brachiopoda
Class: Rynchonellata
Order: Spiriferida
Family: Spinocyrtiidae
Genus: Mediospirifer
Species: Mediospirifer audaculus (Conrad, 1842)

Information

Geological Range

Middle Devonian

Paleogeographic Distribution

Stratigraphic Occurrences

Tully Formation

West Brook Member

Moscow Formation

Windom Member

Kashong Member

Deep Run Member

Mahantango Formation

Clearville Member

Pokejoy Member

Montebello Member

Upper Shale Member

Ludlowville Formation

Wanakah Member

Ivy Point Member

Ledyard Member

Otisco Member

Centerfield Member

Prout Member

Beechwood Member

Hungry Hollow Member

Boyle Formation

Lingle Formation

Skaneateles Formation

Ashantee Member

Pompey Member

Delphi Station Member

Mottville Member

Silica Formation

Plum Brook Formation

Silver Creek Member

Oatka Creek Formation

Pecksport Member

Cardiff Member

Mount Marion Formation

East Berne Member

Delaware Formation

References

Hall, (1867) (as Spirifera medialis): p. 227, pl. 38.

Linsley (1994:) p. 208.

Wilson (2014): pp. 116, 117.

Remarks

Originally described as Delthyris audacula by Conrad in 1842. Recombined as Delthyris medialis by Hall in 1843. Recombined as Spirifera medialis by Hall in 1857. Recombined as Spirifera audacula by Whitfield in 1882. Recombined as Spirifer audaculus by Hall and Clarke in 1893. Recombined as Mediospirifer audaculus by Bublichenko in 1956.

From Wilson (2014, p. 116): “Larger, more robust shell than Mucrospirifer mucronatus, but smaller than Spinocyrtia granulosa (below). Hinge line commonly extending beyond edge of the shell. Often very high concave cardinal area on pedicle valve, with slightly incurved beak. To 40-50 mm.”

From Carlton Brett and Gordon Baird: “Mediospirifer is an abundant medium sized simple spiriferid that occurs in a variety of mudstone and carbonate facies in the Givetian. This species does not occur in the Eifelian but nonetheless other species assigned to Mediospirifer (e.g. M. manni) are present in these older rocks suggesting that the genus is an Eastern Americas Realm. It is an eponymous species of the Athyris-Mediospirifer biofacies (Brett et al., 2007) which typified moderate diversity mid shelf mudstone-siltstone facies, although the Old World Realm taxon Mucrospirifer may dominate in some of the latter silciclastic facies. M. audaculus is quite abundant in some of the oldest representatives of the Hamilton fauna such as the Halihan Hill Bed of the Otsego Member, Mount Marion Formation where Mediospirifer and a small form of Athyris cf. A. cora dominate in some areas forming the earliest typical Athyris-Mediospirifer association.”