Original paper
Phylogenetic trends in phragmocone-bearing coleoids (Belemnomorpha)
Reitner, J.; Engeser, T.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen Band 164 Heft 1-2 (1982), p. 156 - 162
15 references
published: Dec 22, 1982
DOI: 10.1127/njgpa/164/1982/156
ArtNo. ESP155016401037, Price: 29.00 €
Abstract
Traditionally coleoids comprise all endocochlean cephalopods. The classification of fossil coleoids is difficult because of their lack of distinctive features and their low fossilization potential. Three groups (supraorders), however, can be easily distinguished: phragmocone-bearing coleoids (Belemnomorpha), Sepiomorpha and coleoids without phragmocone (Teuthomorpha). Jeletzky (1966) classified the orders of Belemnomorpha according to the proostraca. Donovan (1977) tried to use the arm-crown and protoconch apart from the proostracum. Engeser & Reitner (1981) propose to use only the protoconch for classification at the level of orders. According to the four types of protoconchs observed within the group Belemnomorpha, four orders are distinguished: Aulacocerida, Belemnitida, Belemnoteuthida and Spirulida.
Keywords
coleoids • endocochlean cedphalopods • fossil soleoids • phragmocone