Chacodelphys

Chacodelphys is a recently described genus of didelphimorph marsupials with a single species, the Chacoan pygmy opossum, Chacodelphys formosa. Until 2004 the species was known from only one specimen collected in 1920 in the Chaco of Formosa Province, Argentina, and it remains endemic to a small region of northern Argentina. It is the smallest known didelphid, with a head and body length of 68 mm, a tail of 55 mm and a hind foot of 11 mm, and it differs from other marmosine genera in having a long third manual digit, no distinctly tricolored pelage, a long fourth pedal digit and a tail shorter than the head and body. The animal was first described as Marmosa muscula, renamed Marmosa formosa and moved between genera until Voss and colleagues erected Chacodelphys in 2004.