Original paper

Remarks to the classification and phylogeny of the Ataphridae Cossmann, 1915 (Gastropoda, Archaeogastropoda) in the Jurassic

Gründel, Joachim

Abstract

Species and genera of the Ataphrus-group are common and widely distributed in the Jurassic. The morphology of the aperture and the peristome represents the most diagnostic shell character: The aperture is round, circular and has a crescent-shaped columellar lip, mostly with a furrow. Additional peristome characters may be present. Frequently a callus is also developed. Some species lack this kind of aperture/peristome in mature adults. However, in such species, it is present in earlier ontogenetic stages. 29 genera and subgenera are discussed regarding these apertural/peristome characters. A new classification of the family Ataphridae is suggested. New taxa are the tribe Costataphrini and the subfamily Lewisiellinae. Previous classifications (Knight et al. 1960; Hickman & McLean 1990; Monari et al. 1996; Bouchet & Rocroi 2005) are discussed to facilitate a comparison with the classification presented herein. The columellar lip of the Proconulidae (sensu Gründel 2000) is very similar to that of the Ataphridae and thus, both families are probably closely related to each other. The Ataphridae originate probably in the Triassic with two or three evolutionary lines. A rapid radiation occurred in the Early Jurassic which became manifest in a great number of character combinations reflecting the presence of various evolutionary lines. Most of these lines became extinct in the Jurassic or in the Cretaceous. The most successful, diversified Jurassic group is represented by the Ataphrini. The Colloniini are most diversified in post-Jurassic times.

Keywords

ataphridae (gastropoda)jurassictaxonomyphylogeny