Sigmodon (Sigmomys) alstoni Thomas 1880

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 : 1174

Sigmodon (Sigmomys) alstoni Thomas 1880

Sigmodon (Sigmomys) alstoni Thomas 1880 , Proc. Zool. Soc. Lond., 1880: 691.

Type Locality: Venezuela, Sucre State, Cumaná.

Vernacular Names: Alston's Cotton Rat.

Synonyms: Sigmodon (Sigmomys) savannarum (Thomas 1901) ; Sigmodon (Sigmomys) venester (Thomas 1914) .

Distribution: Intermittently distributed in savannas over NE Colombia, N and E Venezuela, Guyana, Surinam, and N Brazil (regional aspects of range amplified by Husson, 1978; Linares, 1998; and Voss, 1992).

Conservation: IUCN – Lower Risk (lc).

Discussion: Subgenus Sigmomys . Suspected to be "individuals of South American representatives of S. hispidus with grooved incisors" ( Hershkovitz, 1955 a:647), but distantly related to other species of Sigmodon according to phylogenetic interpretation of cytochrome b sequences ( Peppers and Bradley, 2000; Peppers et al., 2002). Voss (1992) discerned no morphological or morphometric foundation for delineating subspecies, but Linares (1998) recognized savannarum and venester , along with the nominate form, as races for Venezuelan populations.