Abstract
Fossils of the raccoon dog (genus Nyctereutes) are particularly rare in the African Plio-Pleistocene record, whilst the sole living representative, Nyctereutes procyonoides, is found in eastern Asia and parts of Europe. In southern Africa, only one fossil species of raccoon dog has been identified - Nyctereutes terblanchei. N. terblanchei is recognised from a handful of Plio-Pleistocene sites in South Africa: Kromdraai, Kromdraai-Coopers and Sterkfontein in Gauteng, as well as Elandsfontein in the Western Cape Province. The validity of this species identification was questioned on the basis of the rarity of southern African fossils assigned to Nyctereutes, that is, fewer than 10 specimens have been identified as Nyctereutes. This study examined this fossil sample of the raccoon dog from the Gauteng sites and compared dental and cranial metrics of the fossil with samples of modern canids and published data. Morphological traits used to distinguish Nyctereutes, such as the pronounced subangular lobe on the mandible and the relatively large size of the lower molars, were observed to be variable in all samples. Analysis showed that the size of the dentition of the southern African fossil samples was larger than that of living raccoon dogs, but fell well within the range of that of African jackals. These results suggest that fossil Nyctereutes cannot be distinguished from other canid species based on metric data alone, and may only be diagnosable using combinations of non-metric traits of the dentition and skull. However, based on the degree of morphological variability of the traits used to diagnose Nyctereutes, as well as the rarity of this genus in the African fossil record, these fossils are more likely to belong to a species of jackal or fox.
Highlights
Modern raccoon dogs belong to a single Asian species, Nyctereutes procyonoides, with six recognised subspecies that are well adapted to colder climates.[1,2] The raccoon dog has been introduced to European countries such as Russia and Finland for commercial farming in the fur industry
The presence of a marked subangular lobe on the mandible is observed in modern raccoon dogs, as well as in the samples of later, more derived fossils of this genus
The validity of the South African raccoon dog as a species is vital to the reconstruction of carnivore guilds which existed in the past, and to understanding the numerous extinctions of Pleistocene faunas
Summary
Modern raccoon dogs belong to a single Asian species, Nyctereutes procyonoides, with six recognised subspecies that are well adapted to colder climates.[1,2] The raccoon dog has been introduced to European countries such as Russia and Finland for commercial farming in the fur industry. There are three jackal species in Africa: the arid-adapted golden jackal (Canis aureus) that occurs in northern and eastern Africa, the black-backed or silver-backed jackal (Canis mesomelas) that is found in eastern and southern Africa and the side-striped jackal (Canis adustus) that is found in sub-Saharan Africa up to the borders of the equatorial forest.[3] DNA studies examining the phylogenetic relationships of 23 extant Canidae species suggest that Canis mesomelas and Canis adustus cluster close together, within a larger group of ‘wolf-like canids’, whilst the raccoon dog clusters with the African bat-eared fox (Otocyon megalotis) in a ‘basal canid’ position.[4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
