The spider, of course, is a favorite icon of Halloween, scampering about on eight legs to trap and devour small insects.
What, then, to make of Bagheera kiplingi?
Christopher J. Meehan, while an undergraduate at Villanova University, found that this small jumping spider has a decidedly unspooky diet: plants.
In a paper this month in the journal Current Biology, Meehan and colleagues say the Mexican critter is the first spider known to have a mainly vegetarian diet.
Its food of choice is something called Beltian bodies - small tips found on the leaves of acacia plants.
Coauthor Eric Olson, of Brandeis University, noticed in 2001 that these spiders seemed to subsist on a plant diet. But his evidence, from observations in Costa Rica, was less conclusive.
The spiders that Meehan saw in Mexico were mainly plant-eaters, with 90 percent of their diet from the Beltian bodies. The rest comes from plant nectar and the occasional nibble of ant larvae.
The researchers confirmed their observations by chemical analysis of the spiders' bodies, revealing the plant-heavy diet.
The spider was first identified in 1896, by naturalists who were fans of Rudyard Kipling. The name Bagheera comes from the panther in Kipling's The Jungle Book.
Though science can be a cutthroat arena, Villanova biologist Robert L. Curry, the paper's senior author, is pleased to note that his group collaborated with Olson.
"Science doesn't always have to be completely competitive," Curry says.
Perhaps they were taking their cue from the non-predatory spider.
- Tom Avril