The taxonomic order Rhynchonellida is one of the two main groups of living articulate brachiopods, the other being the order Terebratulida. They are recognized by their strongly ribbed wedge-shaped or nut-like shells, and the very short hinge line. The hinges come to a point, a superficial resemblance to most (phylogenetically unrelated) bivalve m...
Found on
http://en.wikipedia.org/wiki/Rhynchonellida
(from the article `lamp shells`) ...usually open; dorsal-valve brachiophores supported by bracing plates; impunctate; nearly 100 genera; mid-Cambrian to Late Devonian (350,000,000 ...
Found on
http://www.britannica.com/eb/a-z/r/44
No exact match found.
