Ichneumonoidea
| Parasitic wasps | ||||||||||
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A parasitic wasp of the genus Ephialtes from the subfamily Pimplinae |
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Ichneumonoidea | ||||||||||
| Latreille , 1802 |
The Ichneumonoidea , sometimes referred to as " Ichneumonoidea " in German , are a superfamily of the hymenoptera . According to the usual opinion, it comprises only two families,
- Parasitic wasps (family Ichneumonidae)
- Braconid wasps (family Braconidae),
However, both of which are very species-rich, so that the group includes far more than 40,000 described species, with a significantly higher number of still undescribed species being assumed. Ichneumonoidea develop as parasitoids on other insect species (a few, as an exception, also in arachnids), whereby a large number of ways of life are realized. They are therefore of great importance in the ecological structure of relationships in numerous habitats and are among the most important antagonists of herbivorous (phytophagous) insects. Some species are therefore also used in biological pest control.
features
The body structure has been modified in many ways within the group, so that it is not easy to state all common characteristics. Morphological autapomorphies are: The mandibles of the imagines have two teeth, a sclerite of the trunk section, the prepectus, is fused with the pronotum , on the free abdomen the sternite of the first segment (usually also those of the following segments) is transformed into a sclerotized front (anterior ) and a membranous posterior section, on the first tergite of the free abdomen sit two articular processes (condyles) that articulate with the tergites of the second and third segments. In the fore wing the wing veins Costa, Subcosta and Radius are close together or fused (the Costa cell is missing or, if present, very narrow), and in the hind wing there is at most one transverse artery between the radius and the media. Other useful identifying features are: The thread-like (filiform) antennae are not kneeling, usually with numerous segments, these can reach more than 100 in large species, more typical are around 20 to 60 members, rarely less (minimum 12). The thigh rings of the legs are divided into two parts, the ovipositor of the female is often long and protrudes beyond the end of the abdomen.
The distinction between Braconidae and Ichneumonidae is not always easy. Above all, one feature in the wing veins is characteristic. Only in most Ichneumonidae is the cross vein 2m-cu formed in the distal rear section of the fore wing; in Braconidae it is absent. In the rear wing, the cross artery branches off rs-m after the radius switch artery (Rs) has branched off from the fused longitudinal artery (CR-Rs). In the Ichneumonidae, on the other hand, this cross vein starts before the branching of the fused vein. In numerous Braconidae (much less often in the Ichneumonidae) the wing veins are reduced, especially in the very small species. Wingless Ichneumonidae and Braconidae are not at all easily distinguishable, here the subfamily usually has to be determined. In the Braconidae, the mandibles are usually separated from one another when closed so that their tips do not touch. Otherwise, the leading edge of the clypeus is concave in the Braconidae, straight or convex in the Ichneumonidae.
Biology and way of life
Ichneumonoidea develop as parasitoids , that is, their larvae live parasitically on or inside eggs, larvae, pupae or (rarely) imagines of other arthropods, which they ultimately kill before they develop. As hosts are most significantly butterflies , followed by beetles , other Hymenoptera, Diptera and Schnabelkerfen . Parasitoids of other parasitoids ( hyperparasites ) are common in parasitic wasps, but almost absent in brackish wasps. Few species have developed deviating hosts. A number of genera, best known among them the parasitic wasp genus Hymenoepimecis, parasitize on spiders . Some others parasitize in the ice sacs of spiders or pseudoscorpions .
Few of the more than 40,000 species (as of 2012: 9 species) have become known whose larvae, as a major exception within the superfamily, develop directly in plant tissue, i.e. feed on phytophagus . The brackish wasp Bracon phytophagus lives in fruits of the tree species Protium tovarense ( Burseraceae ) in the cloud forests of Venezuela. In the parasitic wasp family, there are a few species of the subfamily Labeninae that parasitize on bee larvae or hymenoptera larvae which produce plant gall , which after they have completely eaten the host larva can continue to eat on the food supply or gall tissue, i.e. are facultative phytophagous.
Phylogeny and Taxonomy
Earlier editors had delimited the superfamily further than is customary today, with them, for example, the families Stephanidae and Megalyridae were included. This view is no longer held today. While typical Ichneumonoidea are easily recognizable, there was sometimes uncertainty about the position of some basal or strongly deviating representatives. For example, some researchers consider the subfamily Agriotypinae of the parasitic wasps or the subfamily Aphidiinae of the brackish wasps as separate families.
There is still no clarity about the sister group relationship of the Ichneumonoidea. Earlier editors favored the hymenoptera ( Aculeata ) with weirsting stings , which is now considered unlikely. Phylogenomic studies, after comparing homologous DNA sequences, indicate the Proctotrupomorpha , a group of predominantly small hymenoptera (of the superfamilies Platygastroidea , Cynipoidea , Proctotrupoidea , Diaprioidea , Mymarommatoidea , Chalcidoidea ), but this is uncertain and poorly verified.
Individual evidence
- ↑ Donald LJ Quicke: The Braconid and Ichneumonid Parasitoid Wasps: Biology, Systematics, Evolution and Ecology. John Wiley & Sons, 2014. ISBN 978-1-118-90707-8
- ^ A b Michael J. Sharkey & David B. Wahl (1992): Cladistics of the Ichneumonoidea (Hymenoptera). Journal of Hymenoptera research 1 (1): 15-24.
- ^ David B. Wahl & Michael J. Sharkey: Superfamily Ichneumonoidea. Chapter 10 in Henri Goulet & John T. Huber (editors): Hymenoptera of the world: an identification guide to families. Canada Communication Group, Ottawa, Canada 1993. ISBN 0-660-14933-8
- ↑ Saul Flores, Jafet M. Nassar, Donald LJ Quicke (2005): Reproductive phenology and pre-dispersal seed-feeding in Protium tovarense (Burseraceae), with a description of the first known phytophagous `` Bracon '' species (Hymenoptera: Braconidae : Braconinae). Journal of Natural History 39 (42): 3663-3685.
- ↑ John Heraty, Fredrik Ronquist, James M. Carpenter, David Hawks, Susanne Schulmeister, Ashley P. Dowling, Debra Murray, James Munro, Ward C. Wheeler, Nathan Schiff, Michael Sharkey (2011): Evolution of the hymenopteran megaradiation. Molecular Phylogenetics and Evolution 60: 73-88. doi: 10.1016 / j.ympev.2011.04.003
- ↑ Michael J. Sharkey, James M. Carpenter, Lars Vilhelmsen, John Heraty, Johan Liljeblad, Ashley PG Dowling, Susanne Schulmeister, Debra Murray, Andrew R. Deans, Fredrik Ronquist, Lars Krogmann, Ward C. Wheeler (2012): Phylogenetic relationships among superfamilies of Hymenoptera. Cladistics 28: 80-112. doi: 10.1111 / j.1096-0031.2011.00366.x
