Clare Kenyon
What do you get if you cross a vampire with Inspector Gadget?
It is unlikely your first guess was a predatory mosquito larvae striking its prey with an extendable neck. But, if it was (and even if it wasn’t), you may be pleased to know you can watch the whole ghastly scene in slow motion and high resolution for the first time, thanks to some careful recording by Dr. Robert Hancock, a professor of biology at Metropolitan State University of Denver, USA.
Hancock’s latest research paper analyses the anatomical and dynamic processes of the larval strikes of three different species of predatory mosquitoes – those that prey on other organisms (including other mosquito larvae) within the aquatic environment. These strikes take all of 15 milliseconds and it is only now that modern laboratory and imaging equipment can keep up.
Psorophor ciliata strikes prey with an extendable neck. Credit: Hancock et al. 2022.
When he tried to image the strikes in the 1990s, “it was so incredibly fast,” said Hancock. “The only thing that we saw was a blur of action.” Now, armed with a digital high-speed camera, the striking motion of the larvae can be seen in graphic detail. “I saw it first and my jaw dropped, and it still does every time I watch it,” he says.
Two of the mosquito species (Psorophora ciliate and Toxorhynchites amboinensis) strike by shooting their head away from the body and towards the prey on an extendable neck. At the same time, the larva opens its jaws and snaps them shut on the prey.
A third species known as Sabethes cyaneus, which feeds on both other larvae and microorganisms (such as bacteria and algae) uses a swift flick of its tail to sweep prey towards its head where the jaws again clamp down on it.
As both motions occur in just a fraction of a second, the processes require lots of different actions to work smoothly together, indicating “a highly developed, almost reflexive behaviour called a fixed-action pattern”, said Hancock.
Read more: Five slightly disgusting facts about mozzies
There is, however, more to this research on pesky blood-suckers than just fancy footage.
Predatory mosquitoes have been studied for their potential use in controlling other mosquitoes, such as Aedes species – the main carriers of chikungunya, Zika, dengue and yellow fever. The Toxorhynchites species, in particular, is of interest as it can consume up to 5,000 prey larvae before becoming an adult.
If there’s one thing that could possibly make the itchy bite of a mosquito a little bit better, it’s knowing that the larvae to come might be someone else’s meal.
Sabethes cyaneus flicks prey towards its head to grab it. See more videos here. Credit: Hancock et al. 2022