Large Mindoro Forest Mouse - Identification

Identification

The genus Apomys, of which the large Mindoro forest mouse is a member, can be identified by its small size, a long tail, elongate, narrow hind feet, the presence of four abdominal mammary glands, and a large number of skull characteristics. Within this genus, the large Mindoro forest mouse has several specific identifying features, the most important of which are its very thin and short upper incisors, long lower incisors and long snout. The tail and feet are also relatively long, even within the genus Apomys. The characteristics of the incisors are so peculiar that when Ruedas discovered the species, he initially thought he had found a new genus.

The fur of the large Mindoro forest mouse is soft and smooth. The hairs of the dorsal fur are light gray near the root, and dark brown at the tip. Between the normal hairs are many black tactile hairs. This makes the dorsal fur appear dark brown, although recently captured animals have a dark blue-green hue. Some animals are darker around the midline of the back, and all are a lighter colour at the flanks. The colour of the ventral fur varies between animals, with it being a yellow-brown colour in some, slightly lighter coloured than the dorsal fur in others, still others having gray hairs with brown or silver-coloured tips in the ventral fur, and finally some animals showing no difference between the dorsal and ventral fur at all.

The tail is usually an even, dark colour, but in some animals the ventral side is somewhat darker. In some animals the tail ends in a white tip of 2 to 10 mm in length. The tail has fourteen scales per centimeter. The long, dark hind feet end in long claws (about 4 mm). The claws on the front feet are about 3 mm in length. The animal has seven cervical vertebrae, thirteen thoracic vertebrae, six lumbar vertebrae, three sacral vertebrae and thirty-two to thirty-five caudal vertebrae.