Last updated February 6, 2018 at 3:20 pm
A new species of arachnid had a tail longer than its body that acted as antenna.
The new species Chimerarachne yingi, described in two new papers in Nature Ecology and Evolution, shares a lot in common with modern spiders: it has fangs, four pairs of legs, and spinnerets for producing silk at it’s rear.
But the feature that makes it stand out is a tail that’s as long as its body.
“It’s for sensing the environment”, says Paul Seldon from the University of Kansas and one of the authors of the study,
“Animals that have a long whippy tail tend to have it for sensory purposes”
Modern spiders don’t have tails, but other arachnids do – such as scorpions or the little-known vinegaroons or whip scorpions (see below).
So is this find a spider?
Paul Seldon’s team believes it represents a step along the evolutionary pathway to modern spiders.
“The ones we recognised previously were different in that they had a tail but don’t have the spinnerets”, said Seldon.
“That’s why the new one is really interesting, apart from the fact that it’s much younger – it seems to be an intermediate form.
“In our analysis it comes out sort of in between the older one that hadn’t developed the spinneret and modern spiders that has lost the tail.”
Is this ancient arachnid still out there?
Although it had the ability to spin silk, the researchers say that it’s unlikely it spun webs. Spiders use their silk for all sorts of other purposes, from wrapping egg sacks, lining their burrows or just leaving trails to help them navigate their way home.
There’s even the possibility that modern descendants of this ancient fossil may still be living in the rainforests of Myanmar. The fossil example was relatively tiny at only 5mm long, making them easily overlooked in modern biodiversity surveys.
“We know a lot about the Burmese biota during the Cretaceous,” Seldon says.
“It was a pretty good tropical rainforest, and there are a great many other arachnids we know were there, particularly spiders, that are very similar to the ones you find today in the southeast Asian rainforest.
“It makes us wonder if these may still be alive today. We haven’t found them, but some of these forests aren’t that well-studied, and it’s only a tiny creature.”