Original paper

The phylogeny and classification of primitive Placenticeratidae (Cretaceous Hoplitina, Hoplitoidea)

Cooper, Michael R.; Owen, Hugh G.


Phylogenetic analysis of the subfamily Anahoplitinae (sensu Wright 1996) suggests a very different content and classification to that proposed by the Treatise. Since Anahoplitinae are the ultimate source of Placenticeratidae, here Anahoplitinae and descendent Semenoviceratinae are removed from Hoplitidae and transferred to Placenticeratidae as primitive rootstock. Within Anahoplitinae, Lepthoplites is resurrected from synonymy, Hengestites is transferred from Placenticeratidae (sensu Wright 1996), Sulcohoplites post-dates the Treatise and Euhoplitoides n. g. is new. Resurrected Semenoviceratinae, a paraphyletic taxon, embraces Neanahoplites n. g., Planihoplites which was too late for the Treatise, Semenoviceras and broadly-interpreted Karamaites (with numerous alleged synonyms); the latter is the direct ancestor of Late Cretaceous placenticeratines. Neotypes are designated and figured for a number of species.


albiancenomanianammoniteshoplitid provinceplacenticeratidaeanahoplitinaesemenoviceratinaephylogenysystematics