SMITH,G.R.; FINK, S.V. 1990. A review of the boliviensis group of Akodon (Muridae:Sigmodontinae), with emphasis on Peru and Bolivia. Miscellaneous Publications, Museum of Zoology, University of Michihan 177:1-104.
Abstract. We recognize the Akodon boliviensis group as an informal assemblage of species including Akodon boliviensis (western Bolivia and Puno Department, Peru), Akodon puer (subspecies caenosus in northwestern Argentina and southern Bolivia, puer in central Bolivia, and lutescens in Puno Department, Peru and La Paz Department, Bolivia), Akodon subfuscus (subspecies subfuscus in southeastern Peru and La Paz Department, Bolivia; also a new subspecies from southeastern Peru), and Akodon n. sp. (central Peru). We further suggest that Akodon spegazzinii (subspecies spegazzinii and tucumanensis) from northern Argentina may be a member of this group. Akodon pacificus os shown to be a synonym of A. boliviensis. The bolivisneis group is diagnosed by a combination of characters including small size, delicate cranium, narrow and straight-sided mesopterygoid fossa, hourglass-shaped interorbital region, and dull brown fur without contrastingly colored areas.
Descriptions of included species and subspecies are provided. Traditional cranial, dental, and external characters are used in combination with electrophoresis and anatomical features of the soft palates, male reproductive tracts, and hind feet to recognize and diagnose species. Treatment of age-related variation is particularly important to distinguish these species; we document qualitative and quantitative changes in cranial morphology with age (toothwear class) and use regression to allow comparison of individuals of different ages.
We tentatively propose that subfuscus, puer, and the new species form a clade with bolivisneis as its sister group. This hypothesis cannot be subjected to formal test, however, until the condition of relevant characters in potential outgroups is better understood.