What is "pentamerus"

Pentamerus \Pen*tam"e*rus\, n. [NL. See Pentamerous.] (Paleon.) A genus of extinct Paleozoic brachiopods, often very abundant in the Upper Silurian.

Pentamerus limestone (Geol.), a Silurian limestone composed largely of the shells of Pentamerus.

''The gall mite genus Pentamerus, established by Roivainen in 1951, is invalid and needs to be renamed. Until this happens, use Pentamerus (mite).

Pentamerus is a prehistoric genus of brachiopod that lived from the Silurian to the Middle Devonian in Asia, Europe, and North America.