The figure below shows the distribution of samples containing the orthid brachiopod Paucicrura.
Paucicrura is a common orthid brachiopod in the MRV strata.
- Paucicrura Cooper, 1956 [*Orthis rogata Sardeson, 1892] [=Crystiferina Cooper, 1956 (type C. cristata)]
- Ventribiconvex with gently convex sulcate brachial valve; ventral muscle field bilobate, vascula media divergent; cardinal process trilobed with median lobe forming variably developed crest, brachiophore bases divergent relative to their tops.
M. Ord. - U. Ord., North America and Europe.
- Family Dalmanellidae Schuchert, 1913
- Convexo-concave to plano-convex profile, ventral interarea curved, apsacline, dorsal interarea shorter, anacline, delthyrium and notothyrium open, coarsely fasciostellate to finely costellate ornament very rarely with hollow costellae, variably developed dorsal sulcus at least in young growth stages; ventral muscle field usually umbonal, broadly cordate to bilobed, with adductor scar rarely enclosed by median diductor lobes; cardinal process varying from simple ridge to elaborate trilobed myophore with shaft, bases of simple brachiophores variably disposed, fulcral plates commonly developed; dorsal adductor scar quadripartite, mantle canal system commonly lemniscate in both valves.
L. Ord. - L. Carb.
- Order Orthida Schuchert & Cooper, 1932.
Treatise on Invertebrate Paleontology, H336.