WASP STINGER, SEM

Abdomen and stinger of a female wasp from the species Dasymutilla (colorized SEM, x 10).
Wasps from the species Dasymutilla are velvet ants, members of the Mutillidae family. Mutillidae wasps are parasites of other hymenoptera, of which the morphology is intermediate of the wasps and the ants : absence of wing in females, elongated and hairy body, hence their other name of velvet ant. The sting of these wasps is extremely dangerous.

Dasymutilla > Mutillidae > Velvet ant > Wasp > Hymenoptera > Insect.

Under a very low magnification of only 10X, this scanning electron micrograph (SEM) revealed the morphologic details of a female velvet ant’s, Dasymutilla sp., distal abdomen from which her stinger had been exposed. The female velvet ant is not really an ant at all, but a wasp, which merely resembles an ant, hence its name. Its sting is very painful, which has caused it to often be referred to as the “cow killer” ant. However, it was the post-sting festering wound, which would become infested with the now eradicated screw fly that would cause the cow’s death, and not the sting.

Note the head and thorax regions in the background, as well as the three pairs of the insects jointed legs. As a member of the Phylum Arthropoda, i.e., Arthro = “jointed”, and poda “leg”, this insect is supported by a jointed exoskeleton, thereby, facilitating mobility of all of its body parts. It is a member of the Family, Mutillidae, and the Order, Hymenoptera.

Also note the presence of sensorial “hairs” upon the surface of the exoskeleton, which are really not hairs as in the mammalian sense, i.e., composed of keratin, but chitinous extensions composed of the same protein as that of the exoskeleton itself.

The female will invade another subterranean wasp or bee’s nest, paralyzing the larvae inside. It will then lay its eggs in the host larvae or pupae, and upon hatching, the velvet ant larvae will feed on the paralyzed host larvae.