Mormopterus sp dorsal view
The tail extends beyond the tail membrane.

There are a dozen or so species of small insectivorous bats that occur in the Strathbogies. These small bats are commonly referred to as ‘microbats’, to distinguish them from their better known and much larger cousins, the fruit bats (megachiroptera). And many people will have had some experience of these microbats, even if its just to try to encourage a bat that finds itself inside, to fly through an open door to freedom.

Mormopterus sp
Alert, not alarmed!
Mormopterus planiceps (Sp 4 long penis)
The 'free' tail is clearly visible

That’s just what happened at our place two days ago. A microbat found its way inside during the night and I found it in a basin, on the ground, the next day – asleep. About the size of a House Mouse, this little bat was grey in colour and had the distinguishing character of a tail that extends beyond the tail-membrane; most microbats have tails completely enclosed by the membrane. This identified the specimen as one of the freetail bats, in particular the Southern Freetail Bat, previously known as the Southern Mastiff Bat. There are several species of Southern Freetail Bat that have yet to be properly described and named. Currently this little fellow is called Mormopterus planiceps (Sp 4 long penis form), to distinguish it from its less-well endowed Mormopterus cousins.

 

Mormopterus planiceps long penis
Penis & testicles clearly visible.

These bats roost mainly in tree hollows and buildings that have entrances and cavities not much bigger than themselves. They forage above the forest canopy and on the ground, where they are extremely agile. They have a diet of insects including moths, beetles, wasps, bugs, flies and cockroaches and like all microbats, play an important role in controlling insects. Individuals of this species are known to forage widely, up to 12 km from their roost. Females give birth to a single young in December-January. Females reach sexual maturity in their first year, and males in their second.

This species is widespread in Victoria and its conservation status is regarded as secure.

There are at least four species of Freetail Bat in Australia and other species in South America, SE Asia, Africa and Madagascar.

[Reference: Menkhorst (Ed.) 1995 Mammals of Victoria]

For additional info:

South Australian Bat Brochure – a well illustrated poster pdf (1.5 MB)

Moira Shire bat survey – 1.9 MB pdf report