Last week I gave you this mystery object to have a go at identifying:

I thought it would prove tricky and I wasn’t wrong. For starters, it’s not a great photo – you can’t see many of the more distinctive features that might provide a clue, like the face with the nose shape. This wasn’t because I was trying to hide anything, it was simply because things have been very busy recently and I took this photo in a hurry as a record of a new specimen, rather than as an image for the Friday mystery object.

However, there are some clues available. First of all, the wing claw is on a short digit, unlike the long finger that you see in the fruitbats – plus it doesn’t have the big eyes that the fruitbats have so this is one of the microbats. Next, the scale shows that this animal would have a body length around 10cm – which is pretty big for one of the microbats.

Then you don’t have a big visible nose structure, which considering the angle of the photo doesn’t mean there isn’t one, but if it has one it’s not very prominent. In fact, there may be something a bit misleading in that area – a shiny black bump in the nose area that almost looks like a fake nose has been stuck on. This in fact is a bit if a clue as to the identify of this bat.

It’s actually a waxy secretion from just behind the nose that the males of this species produce as a signal to females and, I can attest, it’s quite pungent smelling. This combined with the colour of the fur suggests that this is a Diadem Round-leaf Bat Hipposideros diadema (É. Geoffroy, 1813).

This is a very widespread species with a range from South East Asia to the top of Australia. Because they’re quite large and heavy they’re not very manoeuvrable, so they ambush their prey of large moths and beetles from a perch, launching themselves at anything their sonar picks up as it flies by. In fact these bats are big enough to take small birds and those large canines combined with having a very high bite force mean the Diadem Round-leaf Bat is able to handle these bigger prey and for researchers it’s reported to have a very painful bite.

This particular specimen was presented to the Museum by Customs, who seized it in the post because it lacked the appropriate import paperwork. I’m now in a bit of a quandary about what to do with the waxy secretion on the head. It has gummed down the leaf on the nose and it smells pretty strongly, so it make the specimen less useful for display, but it is still an interesting feature of the biology. It may a case of removing a sample and keeping it in a small tube with the specimen and then cleaning the rest off, so the full beauty of this bat’s face can be revealed.