Larvae of some Perreyia species travel in groups on the ground and eat dead or dying vegetation. They also travel as groups to find group pupation sites. These groups are a tight-knit mass of larvae crawling over each other looking like a giant slug. In the genus Perga, groups come to periodic halts and individuals within the groups begin to raise and lower their abdomens to communicate to the rest of the group to begin moving again. Economic importance Some pergids can be economically important because of their defoliation. Species of Tequus feed on potatoes in Peru and Bolivia, Cerospastus volupis defoliates Nothofagus in Chile and Argentina, a large number of species defoliate (Perginae) or mine in the leaves (Phylacteophaginae) of various species of Eucalyptus in Australia. In particular, the leafminers of the genus Phylacteophaga have been of concern in New Zealand and New Caledonia since being introduced into those countries. Other species of Haplostegus, Enjijus, and Sutwanus feed on the foliage or are shoot borers of guava, Psidium spp., in Central and South America, and Acordulecera species defoliate oaks and hickories in the eastern North American deciduous forests. Some species are of concern to agriculture in Australia (Queensland), Brazil, and Uruguay, where larvae are known to be poisonous to livestock if ingested. Two species are of potential value as biological control agents of invasive weeds in the United States. Lophyrotoma zonalis from Australia has been considered for release against Melaleuca quinquenervia in Florida, and Heteroperreyia hubrichi against the Brazilian peppertree, Schinus terebinthifolius. Subfamilies These 14 subfamilies belong to the family Pergidae: Acordulecerinae Conocoxinae Euryinae Loboceratinae Parasyzygoniinae Perginae Pergulinae Perreyiinae Philomastiginae Phylacteophaginae Pterygophorinae Pteryperginae Styracotechyinae Syzygoniinae References External links Pergidae of the world Traveling group of Perreyiinae Tenthredinoidea Sawfly families