The strepsiptera insect order consists of more than 600 species of small parasites with bizarre behaviors. Their nickname, twisted parasite, is befitting since males of the order have hind wings that twist about when they fly. According to EncyclopediaBritannica.com, insects parasitized by this order include bees, leafhoppers, froghoppers, planthoppers, and treehoppers. Some strepsiptera parasites become free living and others remain inside their hosts.
In classifying insect orders, strepsiptera belong together because of the unusual ways by which they reproduce. For example, most females live their lives inside of their hosts and reproduce at juvenile stages of life. Some females in this order that do not spend their lives inside hosts belong to the Mengenillidae family. Likewise, some females release live larvae that, as do male strepsipteran parasites, go on to become free-living – they discontinue living inside their hosts.
Appearance
Some female strepsiptera have rather plain saclike bodies and do not possess any eyes, wings, legs, antennae, or outer sex organs. On the other hand, females of some of the other strepsiptera families, for instance mengenillidae, do have outer body parts. Just the same however, even mengenillidae do not have wings.
Males, on the other hand, have wings in the rear that look like fans and wings in the front that look like clubs. Males also have large raspberry looking eyes that bulge out on the sides of their heads – the antennae look somewhat like combs. Depending on the species, their legs have between two and five different segments with claws at the ends.
Diet
In some strepsipteran species, the females do not feed on the same types of hosts as the males. In the case of myrmecolacidae, for instance, the females eat from mantids, grasshoppers, and crickets while the males only use ants as hosts.
Mating
Once they spring from their hosts, males fertilize females as soon as possible. They fertilize females through one of two processes. Haemocoelic insemination allows males to fertilize embryos in the females by inserting spermatozoon into different areas of a female’s apodous body called extragenital ducts. The alternate means for implanting spermatozoon involves hypodermic insemination. Hypodermic insemination may occur through openings located below female strepsipteran heads. As many as 600 embryos wait in female abdomens for fertilization.
Larvae
Strepsiptera have two larval stages. They enter their hosts during their first “instar” stage and then molt from stage one into their second instar stage. Females release live larvae, not eggs, through their brood canals. The larvae search for new hosts as soon as they are born. Some parasitic larvae in this order, such as the stylops, wait on flowers for bees to lift them while searching for pollen or nectar. Once bees carry the strepsiptera larvae to their hives the strepsiptera attach themselves to the bee larvae. Another mentionable fact about stylops of the order is that they can remain inside their (bee) hosts from the host larval stage through its morphing into adult bees. Some female strepsipteran parasites do not leave the puparium stage of life.
Habits
Adult males leave their host after they pupate and then proceed to find a female in order to fertilize her young. Male strepsiptera only live for a short time.
Related orders
The strepsipteran and coleopteran orders belong to the superorder coleopteroidea. Unlike some strepsipteran parasites, these orders each have wings, that are made for flying,in their metathorax. The irony here is that the front wings on coleopteroidea parasites are merely hard wing coverings while the strepsipteran forewings are more like short appendages.
According to WhatBugIsThat?, although the strepsipteran order is parasitic in groups such as Thysanura and Mantodea, they prefer to make hosts of Hemipteran insects.
Encyclopedia of Entomology by John L. Capinera
