Jun 17, 2011 – The Ice Tong Mandibles
QUESTION:
One of my technicians brought a bug in today that I simply cannot identify. Unfortunately it looks quite terrifying. The bug is about 3 inches long and woody in color. Mostly gray with some brown mixed in. The head and neck area are just a bit more than 1/2" long with the head being twice the width of the neck. Eyes are on either side of the head and two very long heavy duty mandibles that are curved backward at the ends. The wings are about 2 inches long and heavily veined, each pair being about equal in length.From the bottom the bug's head and neck area are equal to half its body length. The thorax is twice the width of the neck and the abdomen and is tapered. I thought it might be some type of Mantis but cannot find anything that looks similar.
ANSWER:
Normally I shy away from making a definite ID based on just a description, but your description is so beautifully detailed that it is clear to me that you have a male Dobsonfly, a beneficial insect in the family Corydalidae. The male has those amazingly long and curved mandibles and some references say it can inflict a painful bite while other references state the muscles controlling these mandibles are too weak to do much with respect to biting people, and the mandibles are used more for hanging onto the female during mating. But, they are really intimidating, aren't they, along with the huge size of the adult insect. The female looks identical but has much smaller mandibles, and she definitely could give a painful pinch with them if she were handled carelessly.
The larva of the dobsonfly is equally impressive, and for the Eastern Dobsonfly - Corydalus cornutus - it may be as long as 3.5 inches, with strong mandibles of its own. We call the larva a Hellgrammite and it lives under rocks in flowing streams where it feeds on a variety of other aquatic insects that it finds, including those of black flies, so we should thank it for its effort. The larva definitely is capable of giving a painful pinch too. They are used as fish bait and may be raised in captivity and sold in fishing supply stores. The fully developed larva often leaves the water and crawls a short distance over land to find a secluded place to pupate, so they may even be discovered under objects on the soil. The adults may not feed in nature and live only a few days, but during that time they commonly come to lights at night just to scare the bejeebies out of people.
University references on these fascinating insects suggest that there is NO reason to kill them, and given the benefit the larvae provide they should be preserved and enjoyed. Just don't plan on holding one in your bare hand unless you are prepared for the defensive bite.
View past Ask Mr. Pest Control questions.
One of my technicians brought a bug in today that I simply cannot identify. Unfortunately it looks quite terrifying. The bug is about 3 inches long and woody in color. Mostly gray with some brown mixed in. The head and neck area are just a bit more than 1/2" long with the head being twice the width of the neck. Eyes are on either side of the head and two very long heavy duty mandibles that are curved backward at the ends. The wings are about 2 inches long and heavily veined, each pair being about equal in length.From the bottom the bug's head and neck area are equal to half its body length. The thorax is twice the width of the neck and the abdomen and is tapered. I thought it might be some type of Mantis but cannot find anything that looks similar.
ANSWER:
Normally I shy away from making a definite ID based on just a description, but your description is so beautifully detailed that it is clear to me that you have a male Dobsonfly, a beneficial insect in the family Corydalidae. The male has those amazingly long and curved mandibles and some references say it can inflict a painful bite while other references state the muscles controlling these mandibles are too weak to do much with respect to biting people, and the mandibles are used more for hanging onto the female during mating. But, they are really intimidating, aren't they, along with the huge size of the adult insect. The female looks identical but has much smaller mandibles, and she definitely could give a painful pinch with them if she were handled carelessly.
The larva of the dobsonfly is equally impressive, and for the Eastern Dobsonfly - Corydalus cornutus - it may be as long as 3.5 inches, with strong mandibles of its own. We call the larva a Hellgrammite and it lives under rocks in flowing streams where it feeds on a variety of other aquatic insects that it finds, including those of black flies, so we should thank it for its effort. The larva definitely is capable of giving a painful pinch too. They are used as fish bait and may be raised in captivity and sold in fishing supply stores. The fully developed larva often leaves the water and crawls a short distance over land to find a secluded place to pupate, so they may even be discovered under objects on the soil. The adults may not feed in nature and live only a few days, but during that time they commonly come to lights at night just to scare the bejeebies out of people.
University references on these fascinating insects suggest that there is NO reason to kill them, and given the benefit the larvae provide they should be preserved and enjoyed. Just don't plan on holding one in your bare hand unless you are prepared for the defensive bite.
View past Ask Mr. Pest Control questions.
