It's obviously subjective, but likely not too controversial, to proclaim the jumping spiders among the cutest of arachnids. With their stubby legs, big peepers and fuzzy suits, they're almost mammalian-looking, and where other spiders tend to skitter or creep, the "salticids" (as they're also called) dart and hop endearingly, regarding enormous human onlookers with quizzical stances.

As with a sharp-clawed kitten, though, the cuteness of a jumping spider comes with a lethal edge. And a new report from the biological hotspot of India's Western Ghats has revealed an impressive, heretofore unknown salticid menu item.

Scientists conducting a botanical survey around the Kumbharli Ghat mountain pass during the monsoon season of 2014 noticed a lush, cascading rock face dotted with clinging tadpoles, subsequently identified as belonging to the Indirana genus. And the researchers weren't the only ones keying into the pollywogs: a brown jumping spider streaked with black and white was hunting them amid the sheets of falling water.

As the scientists watched, the spider managed to nab one of the tadpoles (armed with sprouting hind legs), and hauled its metamorphic morsel up to a muddy perch on the outcrop.

A salticid spider perched on the water-slicked cliff-face, feeding on a captured tadpole. Image: S. Satpute via Ahmed et al., 2017

"We realised at once that this was a completely new, undocumented behaviour," one of the members of the research team, arachnologist Javed Ahmed, told Stephanie Pappas of Live Science.

In their paper on the sighting, just published in Peckhamia, Ahmed and his colleagues note that other spiders have been known to tackle amphibians; semi-aquatic fishing spiders, for instance, will prey on tadpoles. A study from earlier this year, meanwhile, recorded the regal jumping spider (one of the heftier members of the salticid squad) pouncing on tree frogs, as well as anole lizards, in Florida – the first published report of jumping spiders, which overall are on the diminutive side of things, slaying vertebrates.

Now, the Kumbharli Ghat observation marks the first known instance of a tadpole falling prey to a salticid. While Ahmed and his co-authors aren't certain of this spider's species, they suspect it's a relative of the familiar and widespread Adanson's house jumper, Hasarius adansoni.

Multiple views of the jumping spider clutching its tadpole meal. Image: S. Satpute via Ahmed et al., 2017

But it wouldn't be any sort of shocker if this tadpole-stalking jumping spider turns out to be a brand-new variety. As Ahmed told Live Science, the Western Ghats' "species richness, coupled with a lack of proper research on many groups of invertebrates in the region, means there are several organisms waiting to be discovered, or rediscovered. And that's just what we're doing, discovering spiders one species at a time."

You can keep up with all that arachnid adventuring over at Ahmed's Twitter feed.



Top header image: Mario Madrona/Flickr