The Pleidae family (Pigmy Backswimmers) represents an understudied group of species from the Order Hemiptera and a key had to be done since the most recent American work by Drake and Chapman (1953, Proc. Biol. Soc. Wash., 66:53-60), only provided information on general morphological descriptions and distributional data. The Pleidae are a truly aquatic predacious species which inhabit weedy ponds and lentic water habitats. They feed mainly on ostracods, Daphnia and mosquito larvae. Seven collecting trips to different sites within the Big Thicket performed in May 2006 to July 2006 provided a fair collection of species from the genus Neoplea as well as a borrowed collection from Florida State University.

Results/Conclusions

This key describes five species and two genera. The genus Neoplea Esaki and China, distributed in the Western Hemisphere, and the genus Paraplea Esaki and China, with a North American, Oriental and Australasian distribution. Our species are mostly southeastern in distribution, although Neoplea striola (Fieber) is transcontinental.