Apocrita is a suborder of insects in the order Hymenoptera. It includes wasps, bees, and ants, and consists of many families. It contains the most advanced hymenopterans and is distinguished from Symphyta by the narrow "waist" (petiole) formed between the first two segments of the actual abdomen; the first abdominal segment is fused to the thorax, and is called the propodeum. Therefore, it is general practice, when discussing the body of an apocritan in a technical sense, to refer to the mesosoma and metasoma rather than the "thorax" and "abdomen", respectively. The evolution of a constricted waist was an important adaption for the parasitoid lifestyle of the ancestral apocritan, allowing more maneuverability of the female's ovipositor. The ovipositor either extends freely or is retracted, and may be developed into a stinger for both defense and paralyzing prey. Larvae are legless and blind, and either feed inside a host or in a nest cell provisioned by their mothers.
Alexandr Pavlovich Rasnitsyn is a Russian entomologist, expert in palaeoentomology, and Honored Scientist of the Russian Federation (2001). His scientific interests are centered on the palaeontology, phylogeny, and taxonomy of hymenopteran insects and insects in general. He has also studied broader biological problems such as evolutionary theory, the principles of phylogenetics, taxonomy, nomenclature, and palaeoecology. He has published over 300 articles and books in several languages. In August 2008 he was awarded the Distinguished Research Medal of the International Society of Hymenopterists.
Trigonalidae is a family of parasitic wasps in the suborder Apocrita. They are the only living members of the superfamily Trigonaloidea. Trigonalidae are divided into 2 subfamilies; Orthogonalinae and Trigonalinae. These wasps are extremely rare, but surprisingly diverse, with over 90 species in 16 genera, and are known from all parts of the world. It is possibly the sister group to all Aculeata.
The Mymarommatoidea are a very small superfamily of microscopic fairyfly-like parasitic wasps. It contains only a single living family, Mymarommatidae, and three other extinct families known from Cretaceous aged amber. Less than half of all described species are living taxa, but they are known from all parts of the world. Undoubtedly, many more await discovery, as they are easily overlooked and difficult to study due to their extremely small size.
The Gasteruptiidae are one of the more distinctive families among the apocritan wasps, with surprisingly little variation in appearance for a group that contains around 500 species in two subfamilies and with 6 genera worldwide. They are members of Evanioidea.
Pelecinidae is a family of parasitic wasps in the superfamily Proctotrupoidea. It contains only one living genus, Pelecinus, with three species known from the Americas. The earliest fossil species are known from the Jurassic, and the group was highly diverse during the Cretaceous. Members of Pelecinus are parasitic on larval beetles, flies, green lacewings, and sawflies.
Stephanoidea is a superfamily of parasitic wasps within the Apocrita; it includes only one living family, Stephanidae, as well as the extinct families Ephialtitidae, Aptenoperissidae, Myanmarinidae and Ohlhoffiidae.
Megalyroidea is a small hymenopteran superfamily of wasps that includes a single family, Megalyridae, with eight extant genera and 49 described species. Modern megalyrids are found primarily in the southern hemisphere, though fossils have only been found in the northern hemisphere. The most abundant and species-rich megalyrid fauna is in Australia. Another peak of diversity appears to be in the relict forests of Madagascar, but most of these species are still undescribed.
The dustywings, Coniopterygidae, are a family of Pterygota of the net-winged insect order (Neuroptera). About 460 living species are known. These tiny insects can usually be determined to genus with a hand lens according to their wing venation, but to distinguish species, examination of the genitals by microscope is usually necessary.
Protostephanus is an extinct genus of crown wasp in the Hymenoptera family Stephanidae known from an Eocene fossil found in the United States of America. The genus contains a single described species, Protostephanus ashmeadi placed in the stephanid subfamily Stephaninae.
Spathiopterygidae is an extinct family of small parasitic wasps, known from the Cretaceous of Laurasia and Northern Gondwana. They are suggested to be members of Diaprioidea, in part due to their similarly reduced wing venation. Some members of the group reduced or lost the hindwings entirely.
Electrostephanus is an extinct genus of crown wasp in the hymenopteran family Stephanidae, and is the only genus placed in the subfamily Electrostephaninae. The genus contains four described species, E. brevicornis, E. neovenatus, E. janzeni, and E. petiolatus, placed in two subgenera E. (Electrostephanus) and E. (Electrostephanodes). Electrostephanus is known from several middle Eocene fossils which have been found in Europe.
Serphitidae is a family of microscopic parasitic wasps known from the Cretaceous period.
Embolemidae is a family of small solitary parasitoid wasps with around 70 species in 2 genera distributed around the world. The few species whose biology is known are parasites on planthopper nymphs of the families Achilidae and Cixiidae. There is debate regarding the status of the genus named Ampulicomorpha by Ashmead in 1893, generally considered now to be a junior synonym of Embolemus (e.g.,), though some authorities dispute this (e.g.,)
Jouault, Corentin; Rosse-Guillevic, Simon. "A new genus of praeaulacid wasp from the mid-Cretaceous Kachin amber (Myanmar)". Annales de Paléontologie. 109 (1): 102599. doi:10.1016/j.annpal.2023.102599.
Embolemus is a genus of wasps belonging to the family Embolemidae. There is debate regarding the status of the genus named Ampulicomorpha by Ashmead in 1893, generally considered now to be a junior synonym of Embolemus (e.g.,), as a few authorities dispute this (e.g.,).
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.
Neuroscelionidae is a family of wasps in the superfamily Platygastroidea. It contains only one extant genus, Neuroscelio, with two other genera known from fossils. Members of Neuroscelio are known from Southeast Asia and Australia. Their hosts are unknown.
Geoscelionidae is a family of wasps in the superfamily Platygastroidea. It contains three extant species in two genera, native to South America and Africa, and several other genera known from fossils. It was originally erected as the tribe Geoscelionini within Scelionidae. It was raised to a full family in 2021.
Sparasionidae is a family of wasps in the superfamily Platygastroidea. Known species are parasitoids of the eggs of orthopterans.
