Productus moorefieldanus var. pusillus Girty 1911

Taxonomy

Brachiopod

Kingdom: Animalia
Phylum: Brachiopoda Cuvier 1805
Class: Strophomenata Williams et al 1996
Order: Productida Sarycheva and Sokolskaya 1959
Family: Productidae Gray 1840
Genus: Productus
Species: Productus moorefieldanus var. pusillus
Author Citation Girty 1911

Geological Time Scale

Eon: Phanerozoic
Era: Paleozoic
Period: Carboniferous
Sub Period: Mississippian
Epoch: Late
International Age: Serpukhovian

Stratigraphy

Big Snowy Group
Heath Formation

Provenance

Acquired by: Purchase/Trade

Dimensions

Length: 2 cm

Location

Bear Gulch
Fergus County
Montana
United States

• bear gulch
• carboniferous
• fergus
• heath
• productus
• serpukhovian
• tff-oilshale-br1841

Comments

Together with Bryozoa and other Brachiopods.

Taxonomy from Fossilworks.org,

From Lutz-Garihan 1979, p. 463: “ Shell small; pedicle valve with moderately well-developed ears, convexity unknown because of deformation of shells, but umbo extends somewhat beyond hinge; greatest width at mid-length of valve; ornamentation of pedicle valve consists of rugae and growth lines, some rugae enlarged as nodes occasionally, and in some specimens, some costae develop at about half the distance from posterior but are somewhat irregular; relatively thick spines along hinge and irregularly across valve.

Brachial valve gently concave, with ears: surface ornamentation has a wavy appearance because of sometimes irregular growth lines and rugae; some rugae interrupted by nodes; costae irregularly developed an some brachial valves; but not extending completely to posterior; spines probably absent, some brachial valves convex at center of hinge on exterior for a minute part of length, giving appearance of a node at this position. No interior structures seen.”

Identified by oilshale using Lutz-Garihan 1979.

References:

Girty, G. (1911) THE FAUNA OF THE MOOREFIELD SHALE OF ARKANSAS. DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY.  BULLETIN 439. 1-145

Lutz-Garihan, A.B. (1979) Brachiopods from the Upper Mississippian Bear Gulch Limestone of Montana. Compte Rendu, Neuvième Congrès International de Stratigraphie et de Géologie du Carbonifère. Vol.  5: 457–467pp.

Link: Browse Collections - College of Humanities and Sciences / UM Paleontology Center - University Of Montana (umt.edu)