Juvenile specimens of the short-looped terebratulid brachiopod genus Pseudorhaetina Sandy have been investigated by the use of transverse serial sections. Internal structures indicate a simple brachidium (loop) is present with long flanges in adult specimens; the brachidium is approximately half the length of the dorsal valve; there is no complex loop metamorphosis in the central cavity of the brachiopod (i.e., no median septum). This combination of characters presents a taxonomic problem--Pseudorhaetina can neither be referred with confidence to superfamily Terebratuloidea, nor superfamily Loboidothyridoidea. Consequently Pseudorhaetina is, for the time being, assigned to a new and as yet unnamed superfamily representing a previously unrecognized part of the post-Paleozoic recovery and reradiation of Mesozoic articulate brachiopods (Rhynchonellata of Williams et al., 1996).

You do not currently have access to this article.