According to the study published in the Journal of Arachnology by Swedish and American researchers, regal jumping spiders, members of the jumping spider family Salticidae, can feast on animals two to three times their own body weight.
In an email to National Geographic, Martin Nyffeler, co-author of the study and conservation biologist from the University of Basel, wrote, "I'm very impressed that here is a jumping spider species capable of killing and eating small frogs and lizards."
The author also commented that this is rare behavior for spiders and most likely hasn't been written about before because of the spider's "natural evasiveness."
During his research, Nyffeler came across a total of six reports on the internet documenting examples of regal jumping spiders eating vertebrates in seven counties in Florida. However, his co-authorized study is the first published observation of spiders eating vertebrates.
In one of the reports online, nature blogger Loret Setters described how she observed a one-inch-long spider preying on a Cuban tree frog. (According to National Geographic, regal jumping spiders are among the world's largest.)
In another instance, amateur spider researcher Jeff Hollenbeck spotted a female regal spider chowing down on a Carolina anole lizard.
After witnessing the lizard's demise, Hollenbeck wrote in an email, "I was surprised…. However, I really shouldn't have been."
With their excellent eyesight and ability to kill vertebrates by simply injecting them with venom, it's no surprise these spiders have the upper hand. The regal jumping spiders — prevalent in Florida — are also one of the world's biggest spiders.
In another study published in July in Current Biology, marine biologist Amy Moran and her team describe their discovery that sea spiders pump blood with their guts. This is the first time this has been observed in a complex animal with distinct digestive and circulatory systems.