Two termite species are now interbreeding in Florida, resulting in the creation of a new species of the insect responsible for billions of dollars of damage each year.

The Asian subterranean and Formosan subterranean termites are each invasive species in many areas of the world, damaging many local climates and habitats outside their native lands of east Asia. The two species were believed to breed at different times of the year in Florida, preventing the insects from interbreeding. A new study revealed an overlap between mating seasons, allowing the species to mix.

Researchers recently noted that breeding swarms are now forming at the same time, leading to the production of new termites, which could be even more dangerous than either of the original invasive species. These intermixed termites breed at twice the rate of either parent species, laboratory studies determined. They were also able to establish viable nests for their young.

"Because a termite colony can live up to 20 years with millions of individuals, the damaging potential of a hybrid colony remains a serious threat to homeowners even if the hybrid colony does not produce fertile winged termites. This is especially true when the colony exhibits hybrid vigor as we witnessed in the laboratory," Nan-Yao Su of the Institute of Food and Agricultural Sciences at the University of Florida (IFAS-UF) said.

Asian subterranean termites (Coptotermes gestroi) and Formosan subterranean termites (Coptotermes formosanus) are known as the most damaging insects in the world. Formosan males in the study began to mate with Asian females, which they preferred to females of their own species.

Hybrid species, such as mules, are usually unable to reproduce, and researchers are uncertain whether the intermixed insects are capable of reproduction. Hybrid crops cannot usually thrive more than one or two generations, forcing farmers to continually restock seed supplies.

Termites cause a total of $40 billion of damage each year. Researchers believe the new hybrid termite could migrate outside of Florida, spreading damage across the southeastern United States. Winged males, known as alates, could be the leading edge in their migration out of the Sunshine State.

"This is worrisome, as the combination of genes between the two species results in highly vigorous hybridized colonies that can develop twice as fast as the two parental species. The establishment of hybrid termite populations is expected to result in dramatically increased damage to structures in the near future," Thomas Chouvenc, a researcher at IFAS-UF, said.

Discovery of the new termite species and analysis of their possible impact on the environment was published in the journal Plos One.