Pergidae
Females of Lophyrotoma zonalis on leaf of Melaleuca sp. prior to oviposition
The Pergidae are a family of sawflies. The form- rich family is divided into 14 subfamilies and includes about 440 species. Pergidae live in South America and Australia, a genus in North America.
Features
The Pergidae are morphologically very diverse. While most other sawfly families are well characterizable the construction of the sensor, these are partly filiform at the Pergidae, some with large culled end link, some with tooth-shaped extended ( " combed " ) or laminate extended ( " sawn " ) Scourge members, they can include between four and 29 segments. The best are recognized members of the family of characteristic reductions in Flügelgeäder. Thus, the radial cell is in the forewing always undivided (without cross- vein ), Analzellen missing, or there is rarely a very small present. In hind wings exist neither medial nor Analzellen. Only in this family can be found at the sawflies but also some wingless or short -winged ( brachypterous ) species.
Larvae
The larvae of most species are free-living on plants and have the typical After caterpillar shape of sawfly larvae with sclerotized, round head capsule with einlinsigem larval eye, elongated, caterpillar shape with three Thorakalbeinpaaren and a different number of Scheinfußpaaren the abdomen on. Few species nate in stems ( Enjijus ) or leaves ( Corynophilus, Phylacteophaga ) and have the typical for this way of life regressions on. The free-living larvae are often yellowish or green colored, but often provided with conspicuous warning colors. They are usually somewhat flattened with a broad ventral side and often have lobe-shaped excrescences on the sides of the body, sometimes filamentous Dorsalanhänge on. Some species are uncommon in sawflies, hairy remarkably long. The larvae of the Australian subfamily Perginae that feed on Eucalyptus and other Myrtengewächsen, characteristically have redesigned mouthparts. Enter the inside of the mandibles a rag or brush-like outgrowth, with which they can separate the toxic, many phytochemicals containing oils from the nutritious leafy substance during feeding. Many blattbewohnende larvae raise in threat to her abdomen, thus resulting in a characteristic U-shaped shock position. In this position, toxic or deterrent substances are presented in order to drive predators. The larvae of most species contain toxins, either absorbed by the food plant phytochemicals or even synthesized peptides.
Way of life
Most species feed on leaves of a wide variety of plant species. Among the Australian species particularly many species are specialized on trees of the endemic genus Eucalyptus. The North American Acordulecera species feed on the leaves of various deciduous trees. In most tropical species, especially from South America, the host plant and the way of life is unknown. Is unusual among sawflies that some species are specialized on dead leaf litter on the forest floor or mushrooms. The foliicolous species, the female lays eggs with its ovipositor usually in rows below the epidermis near the midrib, rarely also on the leaf margin, the food plant from. In some species, the females guard the eggs against parasitoids. The hatching larvae eat depending on the type individually or in larger Socialization. Pupation of the mature larvae is usually in a web in the soil or in the leaf litter. Some carnivorous larvae feed on Eucalyptus to the trees in large army trains simultaneously on the trunk down to the ground.
Economic Importance
A number of species are considered pests, especially by defoliation of forest trees. A number of different types of damage Eucalyptus species. The Chilean type Cerospastus volupis caused defoliation on southern beech ( Nothofagus ). Another problem in South America are poisoning of cattle by accidentally mitgefressene, toxic larvae.
Some species are used in biological pest control, mostly against entrained plant species tested. The type Lophyrotoma zonalis is being considered in Florida in use against the introduced as an ornamental plant and threatening propagating niaouli. A use but have not been approved because there are concerns about the toxicity of the larvae.
Dissemination
The species of the family live almost exclusively in Australia and South America, from tropical to cool temperate in widths. Such a distribution image is usually associated with a development on the former southern continent Gondwana in connection with the break-up of the family was split up to today's continents. Unlike some other families with appropriate dissemination the Pergidae missing in South Africa. The family has a single genus, Acordulecera, to North America, north to Canada, spread out, this is also the only species on the Caribbean islands. In the Australasian region they come in addition to Australia and Tasmania, New Guinea, with two species even to Indonesia before. You are missing in New Zealand and New Caledonia (today an introduced species ).
System
The Pergidae belong to the superfamily of sawflies -like. Their sister group is with high probability the family of the brush horn sawflies ( Argidae ). The form- rich family consists of fourteen sub- families living either in Australasia or America.