Scorpion or not?
June 24, 2010
This bug was found at our campsite in the Davis Mountain State Park near Ft Davis, Texas. Pinchers and hard body suggest scorpion but the stinger and fore legs do not match any species I have searched, the bug was very aggressive as well. What is it?
West Texas Camper
Davis Mountain State Park. Ft Davis,Tx.
Hi West Texas Camper,
This is a Giant Vinegaroon, Mastigoproctus giganteus, one of the Whipscorpions which are not true scorpions. Unlike their stinging relatives, Giant Vinegaroons do not sting and have no venom. They do secrete a concentrated acetic acid that smells like vinegar, hence the common name. According to BugGuide: “The vinegaroon is nocturnal and has poor vision. The whiplike tail is used as a sensory organ, as is the first pair of legs, which is not used for walking. Although its tail in unable to sting, this creature can spray an acidic mist from a scent gland at the base of the tail when disturbed. The spray is 85% concentrated acetic acid/vinegar, hence the common name ‘Vinegaroon.’ The heavy pinching mouthparts (modified pedipalps) can also inflict a painful bite. Although very unlikely to attack humans, it can certainly defend itself if provoked.” We have also seen the name Grampus used in literature regarding the Giant Vinegaroon.
Thank you Daniel. Your response is greatly appreciated. The Giant Vinegroon was quite a site for my 11 year old daughter, she was horrified when she saw it while roasting marshmallows around our camp fire. We did notice a vinegar smell in the air and just couldn’t place its origin. Thanks again!