Revision of the Late Cretaceous conifer genus Moriconia

Abstract

The Cretaceous conifer genus Moriconia has been revised in order to (1) establish its true morphology and emend its diagnosis accordingly, (2) decide whether there are indeed two species, (3) discuss the geological and geographical distribution of the genus and (4) discuss its botanical affinity. Based on assessment of all available material, Moriconia americana is characterised as more robust and with shorter branches than the type species M. cyclotoxon. A neotype is established for both species. The stratigraphical range of M. cyclotoxon is determined from the late Cenomanian to the early Maastrichtian, whereas M. americana ranges from the Coniacian to the early Maastrichtian. The botanical affinity of the genus remains questionable. The Cupressaceae are the most likely candidate, but no closely resembling genera could be identified, either fossil or extant.