The Chiriqui brown mouse (Scotinomys xerampelinus), also known as the long-tailed singing mouse, is a species of brown mouse in the family Cricetidae. It is found in cloud forest and paramo at elevations of 2100 to 3400 m in Costa Rica and Panama. Male Chiriqui brown mice sing to attract mates and to warn off other males from their territories. Their songs also serve to repel members of the related, smaller, competing species, the Alston's brown mouse (Scotinomys teguina).