Onychocerus albitarsis

Onychocerus albitarsis, also known as the scorpion beetle, is a species of beetle in the family Cerambycidae from the Amazon and Atlantic forest regions in Brazil, Bolivia, Paraguay and southern Peru.^[2][3][4] It is the only known beetle that has a venomous sting (as opposed to spraying toxins like bombardier beetles or secreting toxins from the body like blister beetles) and the only known arthropod that stings with its antennae.^[2][3] Each antenna ends in a stinger that resembles a scorpion's tail and is connected to a venom gland.^[2][3] The scorpion beetle's sting was known for centuries, being reported as early as 1884, but was not confirmed to be venomous until 2005.^[3] In one case of the beetle stinging a human, a woman experienced significant pain directly after the incident, and redness and itching at the sting site that lasted for a week. In the other case, a man experienced moderate pain directly after being stung and redness that only lasted for an hour.^[2] The other species in the genus Onychocerus appear to be non-venomous, since they lack the structures inside the antennae that are associated with the venom apparatus of Onychocerus albitarsis.^[3]

Onychocerus albitarsis has a head-and-body that is about 2 cm (0.8 in) long and has a variable mottled pattern in yellow-brown, black and white. Little is known about its behavior, but it is phytophagous.^[2]