The Horntails of Florida

The siricid wood wasps are fairly large, cylindrical insects usually exceeding 20 mm in length. Horntail larvae are pests of new timber. After horntails were introduced into New Zealand and Tasmania, as much as 40 percent of the standing timber of Pinus radiata D. Don (Monterrey pine) was destroyed (Taylor 1976). Parasites from the Northern Hemisphere had to be introduced to control this pest. Fortunately, in Florida a wide spectrum of parasites naturally exists which prevents any serious damage. Although harmless, horntail adults look like stinging wasps, and if they emerge from indoor firewood may alarm some people. The last abdominal tergite of the female bears a hornlike projection called the cornus that gives them their common name. The presence of a pair of hard, opaque, raised areas on the metanotum called cencri characterize the suborder Symphyta to which horntails belong. Horntails (Figs. 1-3) are easy to recognize by their large size, long antennae, presence of only one foretibial spur and the terminal cornus. There exist six species in four genera in Florida. Most of the species appear to be rarely collected, and the commonest species in Florida now appears to be an introduced one from Asia, Eriotremex formosanus (Matsumura) (Smith 1996)).