Fossils of ancient walking bats discovered

Fossils of a previously unknown ancient bat species have been discovered in New Zealand, according to a study published in the scientific journal PLOS ONE.

The fossils were found in sediment from the prehistoric Lake Manuherikia.

Only two living species make up the Mystacina genus today, with both species endemic to New Zealand. The new mystacinid has been named Mystacina miocenalis, dating back 16-19 million years ago to the early Miocene period. The discovery of Mystacina miocenalis also suggests that New Zealand and Australian mystacinid lines separated around this time.

According to the study, Mystacina miocenalis is the first recorded pre-Pleistocene member of the Mystacina genus, pushing back its evolutionary history by at least 16 million years. The range of other bat genera date back to as early as 2 million years ago to as far back as 40 million years ago. The family Mystacinidae diverged from other bat families around 41-51 million years ago.

What’s interesting about bats from the Mystacina genus is that they’re semi-terrestrial, with specialized skeletal structures that allow them to walk on all fours on their wrists and feet with their wings furled. They’re also known as burrowing bats because they can also forage for food on the ground.

Based on its teeth, Mystacina miocenalis was an omnivore that fed on insects and spiders as well as nectar, pollen, and fruit, similar to extant Mystacina species. However, Mystacina miocenalis was three times heavier than living Mystacina bats, weighing in at around 40 grams.

“The size of bats is physically constrained by the demands of flight and echolocation, as you need to be small, quick and accurate to chase insects in the dark,” said lead author and vertebrate paleontologist Suzanne Hand of the University of New South Wales. “The unusually large size of this bat suggests it was doing less in-flight hunting and was taking heavier prey from the ground, and larger fruit than even its living cousin.” — Bea Montenegro/BM, GMA News