Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. This ovipositor is often modified into a stinger. The young develop through holometabolism —that is, they have a wormlike larval stage and an inactive pupal stage before they reach adulthood.
Sawflies are wasp-like insects that are in the suborder Symphyta within the order Hymenoptera, alongside ants, bees, and wasps. The common name comes from the saw-like appearance of the ovipositor, which the females use to cut into the plants where they lay their eggs. The name is associated especially with the Tenthredinoidea, by far the largest superfamily in the suborder, with about 7,000 known species; in the entire suborder, there are 8,000 described species in more than 800 genera. Symphyta is paraphyletic, consisting of several basal groups within the order Hymenoptera, each one rooted inside the previous group, ending with the Apocrita which are not sawflies.
The Orussidae or the parasitic wood wasps represent a small family of sawflies ("Symphyta"). Currently, about 93 extant and four fossil species are known. They take a key position in phylogenetic analyses of Hymenoptera, because they form the sister taxon of the megadiverse apocritan wasps, and the common ancestor of Orussidae + Apocrita evolved parasitism for the first time in course of the evolution of the Hymenoptera. They are also the only sawflies with carnivorous larvae.
The Xyelidae are a comparatively species-poor family of sawflies, comprising about 80 extant species in five genera worldwide, and is the only family in the superfamily Xyeloidea. The fossil record of the family is extensive, comprising more than 120 species and including the oldest fossil Hymenoptera species dating back to the Triassic, between 245 and 208 million years ago. Xyelidae are to be regarded as living fossils since they represent one of the oldest lineages of insects and include still extant forms.
Pamphiliidae is a small family within Symphyta, containing some 200 species from the temperate regions of North America and Eurasia. The larvae feed on plants, using silk to build webs or tents, or to roll leaves into tubes in which they feed, thus earning them the common names leaf-rolling sawflies or web-spinning sawflies. Some species are gregarious and the larvae live in large groups. Fossils of Pamphiliidae have been dated to the Jurassic period.
Evaniidae is a family of parasitoid wasps also known as ensign wasps, nightshade wasps, hatchet wasps, or cockroach egg parasitoid wasps. They number around 20 extant genera containing over 400 described species, and are found all over the world except in the polar regions. The larvae of these solitary wasps are parasitoids that feed on cockroaches and develop inside the egg-cases, or oothecae, of their hosts.
Dryinidae is a cosmopolitan family of solitary wasps. Its name comes from the Greek drys for oak: Latreille named the type genus Dryinus because the first species was collected on an oak tree in Spain. The larvae are parasitoids of the nymphs and adults of Auchenorrhyncha. Dryinidae comprises over 1900 described species, distributed in 11 extant subfamilies and 57 genera.
Megarhyssa, also known as giant ichneumonid wasps, giant ichneumons, or stump stabbers, is a genus of large ichneumon wasps, with some species known for having the longest ovipositors of any insects. They are idiobiont endoparasitoids of the larvae of wood-boring horntail wasps. The ovipositor can be mistaken for a large stinger. This is a genus of holometabolous insects within subfamily Rhyssinae that includes 37 species and belongs to Ichneumonidae, the family of wasps with the highest biodiversity in the world.
Xeris spectrum is a kind of horntail or wood wasp, that lives in coniferous forests. It is large wasp with a powerful ovipositor in females. Unlike other Siricid Wood wasps, Xeris spectrum does not have symbiotic fungi to aid its larvae as they burrow in the wood of fir and other conifer trees making it unique in the Siricidae. It is widespread and is found in large parts of Europe, Asia, Africa and North America.
Tremex columba, also known as the pigeon tremex or pigeon horntail, is a species of horntail that is native to eastern and western North America.
Rhyssa persuasoria, also known as the sabre wasp, is a species belonging to the family Ichneumonidae subfamily Rhyssinae. Members of this subfamily, including those of Rhyssa and the allied Megarhyssa, are also known collectively as giant ichneumonid wasps or giant ichneumons.
The sirex woodwasp is a species of horntail, native to Europe, Asia, and northern Africa. Adults vary in length from 9 to 36 mm.
Megarhyssa nortoni, also known as Norton's giant ichneumonid wasp or the western giant ichneumonid wasp, is a species of large ichneumon wasp.
The Ibaliidae are a small family of the hymenopteran superfamily Cynipoidea. Ibaliidae differ from most of the cynipoids by the larvae being parasitoids on other wasp larvae in the group Siricidae. The Ibaliidae comprise three extant genera of fairly large wasps, with a total of 20 species, and is a sister group to the rest of the cynipoids except the small subfamily Austrocynipidae.
Megarhyssa greenei, also known as Greene's giant ichneumonid wasp, is a species of large ichneumon wasp. It is known from the United States and Canada.
Amylostereum is the single genus in the fungal family Amylostereaceae. The genus currently comprises four saprotrophic and parasitic species, which live off living or dead wood. The Amylostereaceae cause white rot in the wood by disintegrating the tissue component lignin. They produce crust-like, partially wavy fruit bodies on the surface of infested trees, which are similar to those produced by Stereum species.
Megarhyssa macrurus, also known as the long-tailed giant ichneumonid wasp or long-tailed giant ichneumon wasp, is a species of large ichneumon wasp. It is a parasitoid, notable for its extremely long ovipositor which it uses to deposit an egg into a tunnel in dead wood bored by its host, the larva of a similarly large species of horntail.
Ypresiosirex is an extinct genus of sawfly in the horntail family Siricidae. The genus is solely known from a single Eocene fossil found in North America. At the time of its description the new genus was composed of a single species named Ypresiosirex orthosemos.
Ibalia leucospoides, the knife-shaped ibalia, is a species of ibaliid wasp in the family Ibaliidae.
Megischus is a genus of crown-wasps in the parasitoid family Stephanidae. There are over 90 species globally distributed throughout the Neotropical, Palearctic, Afrotropical, Oriental, Australasian, and Oceanian zoogeographical regions.
