Chilarchaea quellon trap-jaw spider (courtesy, Hannah Wood, Smithsonian)
Scientists have just identified an new group of tiny spiders that use a sudden burst of stored energy to slam shut their jaws to catch their meals and it has the researchers wondering how the petite arachnids keep such a massive burst of energy until it is time to use it.
An article on The Christian Science Monitor says this species, known as trap-jaw spiders, is part of a super-family, that has evolved to have an unusual head anatomy, which allows them to snatch and hold their prey. And apparently, the action has been refined along four different evolutionary lines, and that leaves scientists with even more questions to ponder.
Hannah Wood, a Smithsonian scientist, described the process in a telephone interview with CSM, saying, “Let’s say we have a little spider specimen, they’re just hanging out and then they detect some potential prey, they detect movement. They go into stalking behavior, using their first pair of legs almost like antennae, waving them around, stroking the ground with them. Then, when they’re in close proximity to the prey, they open their chelicerae and hold them open while they’re searching. When the prey is close enough, the chelicerae snap closed.”
She described chelicerae as highly maneuverable jaw-like mouth parts.
Now, researchers are wanting to find out where and how the massive amount of energy released to cause the ultra-fast slamming shut of the jaws is kept until the precise moment the spider releases it to ensnare its victim. The motion was noted to be far faster than muscle power alone could produce.
Wood tried to explain, ““Think of it like a rubber band that you pull back and then it flicks forward really fast. Somewhere, they’re storing that energy, and our next task is to find out where.”
Other trap-jaw spiders have slower moving jaws that are used to catch flies and a number of other moving prey, so the intriguing process that led to the development of the lightning-fast jaws of these specimens has scientists wondering if they adapted to target a specific prey, such as springtails, which propel themselves off the ground at a rapid rate.
Wood pointed out the study revealed how little we know about spiders and arthropods, adding they are struggling to even describe all the species. The findings from the study were published in the journal Current Biology.