Recent species of Neothyris (Brachiopoda: Terebratellinae)

Abstract

Morphological and behavioural comparison of Neothyris lentleularis lenticularis with other extant members of its genus shows that N. lentieularis eompressa should be elevated to species rank. Recent species of Neothyris all ottur as free-lying populatrons, and the characters which differentiate N. lenticularis and N. compressa are associated with different methods of orientation. Inferences drawn from the morphology of N. dawsoni indicate that the need for orientation may not exist in the environments it occupies.