Welcome to the Treatise on Invertebrate Paleontology!
Please enter a genera name to retrieve more information.
Rhynchotrema
Classification
Phylum:
Brachiopoda
Class:
Rhynchonellata
Order:
Rhynchonellida
Superfamily:
Rhynchotrematoidea
Family:
Rhynchotrematidae
Formal Genus Name and Reference:
Rhynchotrema HALL, 1860a, p. 68
Type Species:
Atrypa increbescens HALL, 1860a, p. 68, OD
Images
(Click to enlarge in a new window)
Fig. 707, $1 a-l$. *from posterior, x4$ (new).
Synonyms
Geographic Distribution
North America, Europe, northern Africa, Urals, Siberia, Kazakhstan, Kirgizia, China, Australia
Age Range
Beginning Stage in Treatise Usage:
Upper Ordovician (Caradoc)
Beginning International Stage:
Sandbian
Fraction Up In Beginning Stage:
0
Beginning Date:
458.18
Ending Stage in Treatise Usage:
middle Silurian (Wenlock)
Ending International Stage:
Homerian
Fraction Up In Ending Stage:
100
Ending Date:
426.74
Description
Shell small to large with subtriangular to subpentagonal outline and equibiconvex profile, lateral and anterior margins generally steep. Beak suberect to incurved, delthyrium partly closed by marginal deltidial plates. Dorsal fold and ventral sulcus arising at umbones, anterior commissure uniplicate, tongue trapezoid, dentate. Costae subangular, simple, arising at beaks. Dental plates short, almost vertical, teeth stout, with large fossettes, ventral muscle field flabellate. Septalium with distinct septalial plates, dorsal median septum low, thick, extending to midlength, crural bases arising from septal plates, crura long, ventrally curved, cardinal process septiform.
References
Museum or Author Information
Classification
Phylum:
Brachiopoda
Class:
Rhynchonellata
Order:
Rhynchonellida
Superfamily:
Rhynchotrematoidea
Family:
Rhynchotrematidae
Formal Genus Name and Reference:
Rhynchotrema HALL, 1860a, p. 68
Type Species:
Atrypa increbescens HALL, 1860a, p. 68, OD
Images
(Click to enlarge in a new window)
Fig. 707, $1 a-l$. *from posterior, x4$ (new).
Synonyms
Geographic Distribution
North America, Europe, northern Africa, Urals, Siberia, Kazakhstan, Kirgizia, China, Australia
Age Range
Beginning Stage in Treatise Usage:
Upper Ordovician (Caradoc)
Beginning International Stage:
Sandbian
Fraction Up In Beginning Stage:
0
Beginning Date:
458.18
Ending Stage in Treatise Usage:
middle Silurian (Wenlock)
Ending International Stage:
Homerian
Fraction Up In Ending Stage:
100
Ending Date:
426.74
Description
Shell small to large with subtriangular to subpentagonal outline and equibiconvex profile, lateral and anterior margins generally steep. Beak suberect to incurved, delthyrium partly closed by marginal deltidial plates. Dorsal fold and ventral sulcus arising at umbones, anterior commissure uniplicate, tongue trapezoid, dentate. Costae subangular, simple, arising at beaks. Dental plates short, almost vertical, teeth stout, with large fossettes, ventral muscle field flabellate. Septalium with distinct septalial plates, dorsal median septum low, thick, extending to midlength, crural bases arising from septal plates, crura long, ventrally curved, cardinal process septiform.