Karyotypic Variation in Peromyscus boylii from Mexico

Molecular Phylogenetics of the Peromyscus boylii Species Group (Rodentia: Muridae) Based on Mitochondrial Cytochrome b Sequences

“…Members of this group occupy a variety of habitats, ranging from arid scrublands to pine-oak and cloud forests (Schmidly et al, 1988), but typically occur in pine-oak forests of montane regions at elevations higher than 1500 m. Currently 10 species are contained within the boylii species group (Osgood, 1909;Hooper, 1968;Carleton, 1977Carleton, , 1989Rennert and Kilpatrick, 1986;Houseal et al, 1987;Schmidly et al, 1988;Bradley et al, 1996) P. attwateri, P. boylii, P. beatae, P. levipes, P. madrensis, P. pectoralis, P. polius, P. sagax, P. simulus, and P. stephani. Hereafter these taxa are referred to by specific or subspecific epithets.…”

“…Historically, members of the aztecus and boylii groups were classified within the same species group (Osgood, 1909;Hooper, 1968). However, more recent studies have provided morphological (Carleton, 1977;Carleton et al, 1982;Bradley and Schmidly, 1987) and chromosomal (Schmidly and Schroeter, 1974;Houseal et al, 1987;Smith et al, 1989) evidence that the boylii and aztecus groups are two distinct moieties. Carleton (1989) summarized this evidence and elevated the aztecus assemblage to the rank of species group.…”

“…For example, attwateri and pectoralis have been aligned to the truei group and to P. eremicus (Avise et al, 1974a(Avise et al, , 1979Zimmerman et al, 1975;Stangl and Baker, 1984;Janecek, 1990;DeWalt et al, 1993a). Similarly, polius and sagax were placed tentatively in the boylii group (Hoffmeister, 1951;Bradley et al, 1996); however, comparisons of allozymic and karyotypic data resulted in weak or no association of these taxa to the boylii group Zimmerman et al, 1975;Schmidly et al, 1985;Houseal et al, 1987;Bradley et al, 1996). Third, although the systematics of taxa occurring in eastern Mexico have been resolved relatively well (Rennert and Kilpatrick, 1986;Bradley and Schmidly, 1987;Houseal et al, 1987;Schmidly et al, 1988;Castro-Campillo et al, 1999;Bradley et al, 2000), those taxa occurring in western Mexico present several unresolved issues.…”

“…Similarly, polius and sagax were placed tentatively in the boylii group (Hoffmeister, 1951;Bradley et al, 1996); however, comparisons of allozymic and karyotypic data resulted in weak or no association of these taxa to the boylii group Zimmerman et al, 1975;Schmidly et al, 1985;Houseal et al, 1987;Bradley et al, 1996). Third, although the systematics of taxa occurring in eastern Mexico have been resolved relatively well (Rennert and Kilpatrick, 1986;Bradley and Schmidly, 1987;Houseal et al, 1987;Schmidly et al, 1988;Castro-Campillo et al, 1999;Bradley et al, 2000), those taxa occurring in western Mexico present several unresolved issues. For example, specimens occurring in Nayarit, northeastern Michoacá n, and Jalisco, with atypical fundamental numbers of 65, 66, and 68, are morphologically and karyotypically distinct from levipes, beatae, or boylii (Schmidly and Schroeter, 1974;Carleton et al, 1982;Houseal et al, 1987;Bradley et al, 1989;Smith et al, 1989).…”

“…Third, although the systematics of taxa occurring in eastern Mexico have been resolved relatively well (Rennert and Kilpatrick, 1986;Bradley and Schmidly, 1987;Houseal et al, 1987;Schmidly et al, 1988;Castro-Campillo et al, 1999;Bradley et al, 2000), those taxa occurring in western Mexico present several unresolved issues. For example, specimens occurring in Nayarit, northeastern Michoacá n, and Jalisco, with atypical fundamental numbers of 65, 66, and 68, are morphologically and karyotypically distinct from levipes, beatae, or boylii (Schmidly and Schroeter, 1974;Carleton et al, 1982;Houseal et al, 1987;Bradley et al, 1989;Smith et al, 1989). A second form with fundamental numbers ranging from 54 to 56 occurs in central and southwestern Durango, inhabiting desert and montane oak forests (Lee et al, 1972;Schmidly and Schroeter, 1974;Kilpatrick and Zimmerman, 1975;Houseal et al, 1987).…”