Earliest African neornithine bird: A new species of prophaethontidae (Aves) from the Paleocene of Morocco

Abstract

ABSTRACT A new taxon of the Prophaethontidae (Aves) is described from the phosphatic beds of the Ouled Abdoun Basin, Morocco. Lithoptila abdounensis gen. et sp. nov. is represented by a single, well-preserved neurocranium, dated as upper Paleocene (Thanetian) on the basis of the selachians identified in the matrix. This specimen is the oldest known African neornithine bird and the oldest record of the Prophaethontidae. It bears some striking resemblance to Prophaethon shrubsolei Andrews, 1899, from the lower Eocene (Ypresian) London Clay of the Isle of Sheppey, England. Aside from general proportions of the neurocranium, this new taxon differs from Prophaethon shrubsolei in many respects, such as the shape and position of the crista temporalis, impressio glandulae nasalis, surface of contact with the os lacrimale, and tuberculum basilare. This justifies its assignment to a new genus and species. A cladistic analysis of 47 osteological characters supports the monophyly of the Prophaethontidae and a sister-group relationship between the Prophaethontidae and Phaethontidae. The Pelecaniformes are polyphyletic, and the clade comprising the Phaethontidae and Prophaethontidae is the sister-group of the Procellariiformes.