Phyllotis xanthopygus Waterhouse 1837

Wilson, Don E. & Reeder, DeeAnn, 2005, Order Rodentia - Family Cricetidae, Mammal Species of the World: a Taxonomic and Geographic Reference (3 rd Edition), Volume 2, Baltimore: The Johns Hopkins University Press, pp. 955-1189 : 1163

Phyllotis xanthopygus Waterhouse 1837

Phyllotis xanthopygus Waterhouse 1837 , Proc. Zool. Soc. Lond., 1837: 28.

Type Locality: Argentina, Santa Cruz Prov., coast of Santa Cruz.

Vernacular Names: Yellow-rumped Pericote.

Synonyms: Phyllotis abrocodon Thomas 1926 ; Phyllotis arenarius Thomas 1902 ; Phyllotis capito (Philippi 1860) ; Phyllotis chilensis Mann 1945 ; Phyllotis glirinus (Philippi 1896) ; Phyllotis lanatus (Philippi 1896) ; Phyllotis oreigenus Cabrera 1926 ; Phyllotis posticalis Thomas 1912 ; Phyllotis ricardulus Thomas 1919 ; Phyllotis rupestris ( Gervais 1841) ; Phyllotis vaccarum Thomas 1912 ; Phyllotis wolffhuegeli Mann 1944 .

Distribution: WC Perú, in and along the Andes to Santa Cruz Prov., S Argentina, and adjacent Magallanes Prov., S Chile; latitudinal (15-51ºS) and altitudinal ranges (sea level- 5600 m) exceptional as currently defined (see Kramer et al., 1999:Fig. 3, for extent of geographic races).

Conservation: IUCN – Lower Risk (lc).

Discussion: Viewed as a geographic race of P. darwini by Pearson (1958), Cabrera (1961), and Hershkovitz (1962). Morphometric, electrophoretic, karyotypic, and molecular differentiation supports the specific recognition of P. xanthopygus ( Spotorno and Walker, 1983; Steppan, 1998; Walker et al., 1984); genetic diversity among and within isolated Patagonian demes examined by Kim et al. (1998), who postulated the early Pleistocene origin of haplotype lineages and highlighted the vicariant influence of the Río Chubut. Steppan (1998) noted the need for continued systematic examination of the populations now assigned to the highly variable xanthopygus : e.g., chilensis is sometimes treated as a species ( Anderson, 1997); rupestris and vaccarum ( Spotorno et al., 2001) appear distinct from xanthopygus in phylogenetic analysis of abbreviated cytochrome b sequences ( Spotorno et al., 2001); xanthopygus paraphyletic with respect to P. limatus in broader molecular survey of nominal subspecies ( Kuch et al., 2002). See Kramer et al. (1999, Mammalian Species, 617).