Mystacinidae

Mystacinidae is a family of bats known as New Zealand short-tailed bats, with one living genus, Mystacina, comprising two species. These medium-sized bats, measuring about 6 cm in length and covered in grey, velvety fur, have unique characteristics. They often spend time on the ground, can fold their wings into a leathery membrane, and possess an extra projection on some claws for digging or climbing.

Their omnivorous diet includes fruit, carrion, ground-dwelling arthropods, pollen, and nectar, which they collect with extensible tongues. They sometimes create burrows in rotting wood or roost in rock crevices and seabird burrows. While often thought to have evolved their terrestriality due to island endemism, evidence suggests these adaptations may have developed prior to arriving in New Zealand, indicating they coexisted with land mammals.

These bats give birth to a single young each summer and can hibernate in winter. In 2010, a feral cat was found responsible for the death of over 100 short-tailed bats in a forested area of Mount Ruapehu.