Out of Europe: Investigating Hystrix cristata (Rodentia: Hystricidae) skull morphometric geographic variability in Africa

The crested porcupine Hystrix cristata is one of the most well-known members of the Family Hystricidae, yet very little is known regarding its geographic variability in Africa. Two alternative hypotheses exist; pre-1940s classical taxonomy supported the existence of a distinct Eastern African species, Hystrix galeata, whereas recent molecular data seem to support only a North-South separation inside one single species, with the geographic-ecological barrier represented by the Sahara desert. Our morphometric data support the recognition of Hystrix cristata senegalica Cuvier, 1822 as the sub-Saharan representative of the species with a clear morphological difference between the North African and sub-Saharan crested porcupines, which seem re-conductible mostly to size difference. Within H. c. senegalica, our analysis seems to support a weak separation between the West African and the East African samples. Owing to considerable qualitative skull differences and overlooked molecular data, the taxonomic status of H. galeata remains uncertain as well as the status of porcupines of North-East Africa (Nubia). Our results also highlight the role of North Africa (mainly the Maghreb) as a refuge for the nominal taxon. This suggests that intraspecific variability is presently overlooked and that further integrative studies and more samples are needed to adequately assess the geographic variability of sub-Saharan crested porcupines.