The Canis tangle: a systematics overview and taxonomic recommendations

V Dinets

doi:10.18699/vj15.036

Abstract

Despite high research interest, the systematics and taxonomy of mammalian genus Canis are among the most convoluted and controversial: species boundaries are blurred and incongruent with any existing species concept, while genetic differences between species are low. I provide an overview of existing controversies, the most recent findings, and taxonomic possibilities, and recommend the most practical and well-substantiated solutions. The genus boundaries have to be changed, with two African jackals (C. adustus & C. mesomelas) moved to a separate genus Lupulella. The systematic status of taxa occurring in eastern North America has caused much argument; most recent data indicate that Algonquin (C. lycaon lycaon) and Red (C. l rufus and recently exterminated subspecies) Wolves originate from ancient hybridization and should be considered a separate species, while two other populations are of more recent hybrid origin. The systematic position, intraspecific classification, origin and taxonomy of Dog (C. familiaris) are particularly controversial. It has been alternatively classified as a subspecies of Gray Wolf (C.lupus), a subspecies of Dingo (C. dingo), or a full species (C. familiaris) with Dingo as a subspecies. Analysis of available data shows that Dog should be classified as a full species with four subspecies, since its origin from a common ancestor with modern Gray Wolf has likely predated its domestication (contrary to the most popular view), and interbreeding between Dog and Gray Wolf in the wild is limited. It is possible that never-domesticated Dog populations have survived in southeastern Asia until very recently, or even exist today.

Highlights

The bibliography on their phylogeny is so extensive that its sheer volume can make it difficult to keep perspective, as illustrated by persistent misconceptions criticized by Koler-Matzniсk (2002), so it appears that a concise overview of the subject and the most recent developments in the area is needed
Most interestingly, Pariah Dog of Asia hardly ever hybridizes with sympatric Gray Wolf, despite the fact that both forms coexist in very close proximity and are similar in size (Koler-Matznick, 2002, pers. obs.)
The author suggests Canis variabilis, an extinct wolf that occurred in present-day China 100–200 kya, as the most likely candidate, and notices that since it was sympatric with C. lupus sensu stricto in time and space, it was already a separate species

Summary

Introduction

Since African Wild Dog has very distinctive morphology (including dentition) and behavior (Sillero-Zubiri, 2009), the optimal solution seems to separate the two jackals into Lupulella, maintain Lycaon as a separate genus, but merge Cuon into Canis. The status of these two forms has been a matter of intense controversy; they have been considered one or two independently evolved species (Wilson et al, 2004; Chambers et al, 2012), hybrid swarms (Wayne, 1991; Koblmuller et al, 2009), or subspecies of Gray Wolf (Lawrence, Bossert, 1975).

Results

Conclusion