Scientists Discover Previously Unknown Species of Horseshoe Bats

The world might think that one was quite enough, but horseshoe bat species number beyond 100, scientists say

A horseshoe bat.
Jens Rydell / courtesy of Paul Webala

The world might think that one was quite enough. But there are evidently more than 100 species of our friend the horseshoe bat, science announced on Wednesday, unveiling the previously unsuspected existence of another 12 species of the insectivorous aviating mammals in East Africa.

In other words, the bats in East Africa had been known, but the fact that they weren’t the same bat was news to the world.

“We found a lot more species than we thought were there,” said Bruce Patterson, curator of mammals at the Field Museum of Natural History in Chicago.

Horseshoe bats exist throughout much of Africa and Europe, including the UK – the “Old World.” Most are very small, easily fitting in the palm of your hand. If you take one in hand – probably a dead one, because the live ones don’t like that – you will discover that their fur is extremely soft. The reason they are called horseshoe bats is their extraordinary nasal equipage, which somebody sometime thought looked like a horseshoe. It doesn’t, really, unless there is something seriously wrong with one’s horse.

A horseshoe bat whose species designation will likely change to a brand-new species in the next steps of this research.
Bruce Patterson, Field Museum

Possibly the horseshoe bat’s speciation escaped notice because nobody wanted to look at them closely. Let’s face it, they do not attract the eye, they make it hurt. Talk about a face only a mother could love, if she was blind. It took genetic sequencing of dead bats to work out that they had found up 12 new species, bringing the total above a hundred, reported researchers from the Field Museum, National Museums of Kenya, and Maasai Mara University in the journal of BMC Evolutionary Biology.

The upshot is that the researchers found a lot of unknown horseshoe bats, cast doubt on the validity of other recognized horseshoe bat species, and found creative ways to convey their admiration for the whole lot.

“Their comically large ears are only rivaled for wackiest feature by their nose leaves, little flaps of skin that spread outward from their faces like petals,” the biologists lovingly describe. Other descriptions could mention their beady little eyes, though in contrast to previous conventional wisdom, horseshoe bats can apparently see, and well, day or night.

Why did the researchers sequence the dead bats, anyway? To gain insight on bat evolution. Bats have been maligned throughout history, almost always without reason. The odd bat can be responsible for the transmission of zoomorphic illness, one possibly being Ebola that can be caught from fruit bats that serve as a viral reservoir.

Female fruit bats.
S. Greif

Then there are the vampire bats, of which there are also more than one species. They do live on blood but are a lot smaller than most people realize. Vampire bats live in the Americas and max out at three and a half inches in length and weigh the same as a Mars bar. There used to be giant vampire bats, Desmodus draculae, which were a terrifying four inches long, and weighed about the same as a Mars bar with its wrapping. But worry not, they are extinct.

As for the nose gear on extant horseshoe bats, it may look like an accident in Georgia O’Keeffe’s studio but the fact is, those “leaf-like” skin extrusions are key to its navigation. Horseshoe bats emit echolocation squeaks not from their little mouths but through their nostrils, and use the “nose-leaves” to direct their sonar beams.

Different parts of their nose-leaves are tuned to different frequency ranges, concluded a separate study in 2013, published in Frontiers in Physiology. Admit it, your nose can’t do that. Respect.  

A separate study dating to 2015 published in PLoS One looked into the aerodynamic qualities of the bat face, noting that the elaborate nose-leaves of the horseshoe bats would intuitively counter the principle of streamlining. In other words, they would create air drag as the bat flew. Research with bat species in wind tunnels found the facial decoration does create “considerable drag” – but they also create “substantial lift.” Ergo, the bat flies fine and its face doesn’t get in its way. 

The fact is that for all their bad rep, their animal rights aside, bats are enormously beneficial to humans: from the one that eat insects we don't like, such as mosquitoes, to the fruit bats, which farmers may malign - but they are key to pollination. 

Horseshoe bats specifically are insectivores, which means they eat bugs, and that alone makes them our friends. One bat may eat thousands of insects such as mosquitoes each day. With all due respect to insectageddon, given the threat climate change-induced spread of insect-borne disease, it is high time to learn a heartfelt appreciation of these strange-looking animals.

Let us take a cue from Terry Demos, postdoctoral researcher and lead author of the paper: “You could say there’s beauty in the elaborateness of the nose, I mean it is so intricate.”