Taxonomic Review of Cottontails, Sylvilagus floridanus and Sylvilagus nuttallii, in Arizona

Abstract

In Arizona, the two cottontails Sylvilagus floridanus and Sylvilagus nuttallii inhabit montane and submontane terrain. In this region they exhibit considerable morphological convergence and often have been confused. However, we have found several characters which will satisfactorily distinguish the two. Additional material now available together with that already present in various collections has enabled us to present a critical appraisal of the characteristics and geo- graphic occurrence here of the subspecies of S. floridanus and S. nut- tallii. A new subspecies of S. floridanus is described. S. nuttallii pinetis is redefined since previous descriptions were based on specimens of both S. nuttallii and S. floridanus. One specimen is discussed which may be a hybrid between the two species. A taxonomic review of cottontails of the species Sylvilagus flori- danus and Sylvilagus nuttallai in Arizona is called for in view of the confusion that has long existed in distinguishing these two species. Nelson (1909:199) in his revision of the rabbits of North America regarded certain specimens from the Hualpai Mountains and from near Prescott as Sylvilagus nuttallii and used them in his characteri- zation of the subspecies S. n. pinetis (Allen). Some 40 years later, Hall and Kelson (1951:54) regarded these same specimens as being Sylvilagus floridanus holzneri (Mearns). Certain specimens in some