Peromyscus melanotis J. A. Allen and Chapman 1897

Bradley, Robert D., Francis, James Q., Platt II, Roy N., Soniat, Taylor J., Alvarez, Daysi & Lindsey, Laramie L., 2019, Mitochondrial Dna Sequence Data Indicate Evidence For Multiple Species Within Peromyscus Maniculatus, Special Publications of the Museum of Texas Tech University 70, pp. 1-59 : 23

Peromyscus melanotis J. A. Allen and Chapman 1897

Peromyscus melanotis J. A. Allen and Chapman, 1897:203 .

Holotype.— American Museum of Natural History (catalog number MO-10822 ); adult male; skin, skull, and skeleton. Original number 1,268 of Frank M. Chapman .

Type locality.— Mexico: Veracruz; Las Vigas ; collected 23 April 1897.

Subspecies.— Recognized as a monotypic assemblage.

Diagnosis.— Size small for species group; measurements obtained from Osgood (1909) for several of the subspecies now assigned to P. melanotis , indicated a total length averaging 150 mm; (range 132–168 mm) and tail length averaging 62 mm (range 58–66 mm). Osgood (1909) further indicated that cranial measurements suggest a broad and more rounded braincase, auditory bulla is slightly smaller, and long rostrum. Pelage is very long, sides are a tawny ochraceous color.

Distribution.— Occurs in high elevation habitats in Chihuahua and southern Coahuila southward to Jalisco and central Veracruz ( Hall 1981; Musser and Carleton 2005). Populations also occur in the upper montane regions in southern Arizona ( Bowers et al. 1973).

Comparisons.— A species in the P. maniculatus species group. Morphologically similar to P. labecula ( Osgood 1909) , although smaller in overall length and tail length. Further, Cyt b sequences (this study) indicated that P. melanotis differs from P. sonoriensis , P. gambelii , P. labecula , and P. sejugis (four species in close geographic proximity to P. melanotis ) by 6.02%, 5.31%, 5.90% and 4.80% respectively. Genetic differentiation (= 1.82%) based on DNA sequences obtained from five individuals of P. melanotis indicated one of the highest levels of genetic divergence for members of the P. maniculatus species group, despite the low sample size examined for this species.

Remarks.— Six samples were examined in this study that are assignable to P. melanotis . Of these samples, the closest examined herein was approximately 40 km (southwest of the type locality in Las Vigas, Veracruz.

Recognition of P. melanotis as a species, has been supported by phenotypic differences ( Osgood 1909), ecology and elevation data ( Álvarez-Castañeda 2005), unique chromosomal attributes ( Bowers et al. 1973), allozyme data ( Greenbaum et al. 1978; Avise et al. 1979; Rogers and Engstrom 1992), and molecular data ( Hogan et al. 1997; this study). Blair (1950) suggested that P. melanotis is likely a peripheral isolate of P. maniculatus ancestral stock; a position that is supported by the unique and monomorphic karyotype (FN = 62, Bowers et al. 1973; Greenbaum et al. 1978).

Based on divergence time estimates and phylogenetic interpretations, it appears that P. melanotis is the most basal member of the P. maniculatus species group and diverged from all other members of the P. maniculatus species group approximately 1.98 mya. This date is the oldest date recovered for any member of the P. maniculatus species group.