Recently, researchers at Oxford University in the United Kingdom and at Texas A&M University discovered that members of the insect order Strepsiptera pose as their hosts. That may open doors for management of fire ants and other insects. It has also led to more avenues for research.

While serving as a Research Fellow at Oxford a couple of years ago, Dr. Spencer Johnston, entomologist with the Texas Agricultural Experiment Station, was observing work by Dr. Jeyaraney Kathirithamby, who is a researcher with Oxford's department of zoology.

Kathirithamby studies Strepsiptera, a small insect which spends part of its life as an endoparasite or a parasite that develops in the abdomen of its insect host.

"Only the first instar and the short-lived male are free-living," Johnston said. Insects shed their shells in order to grow and then form new ones, he explained. These changes are called in-stars.

"The developing male and the female are wholly endoparasitic in insects."

Strepsiptera "are poorly understood and so exotic," Johnston said. "The male and female look completely different."

Both use the same mechanism the tiny, first instar stage to attack hosts. The ones that attack ants develop into males, and the ones that attack crickets, grasshoppers and mantids turn into females. All of the hosts of the female, and in particular, crickets, are a favorite part of the fire ants' diet, he said.

During his visit to Oxford, Kathirithamby showed Johnston some sections of Strepsiptera DNA. He noticed extremely large nuclei and what appeared to be bags surrounding the parasite. Johnston suggested she should check it out.

After Johnston's return to the United States, Kathirithamby sent him samples of the bags, pa
'"/>

Contact: Edith Chenault
e-chenault1@tamu.edu
979-845-2886
Texas A&M University - Agricultural Communications
8-Aug-2003