Sigmodontomys aphrastus (Harris, 1932) . Occas. Pap. Mus. Zool., Univ. Michigan, 248:5.

TYPE LOCALITY: Costa Rica, San José Prov., San Joaquin de Dota, 4000 ft .

DISTRIBUTION: Known only from the type locality and Chiriqui Prov., W Panama.

COMMENTS: Usually listed as a species of Oryzomys of uncertain relationship (Hall, 1981). Assignment to Sigmodontomys tentative following the observations of Ray (1962). Distribution meagerly documented, known by only three specimens.