abstract:Sigmodontomys aphrastus, also known as the Long-tailed Sigmodontomys,Musser and Carleton, 2005 Harris's Rice Water Rat, or Long-tailed Rice Rat,Duff and Lawson, 2004 is a species of rodent in genus Sigmodontomys of family Cricetidae. It is known from Costa Rica, Panama, and Ecuador.