The Trachypachidae are a family of beetles that generally resemble small ground beetles, but that are distinguished by the large coxae of their rearmost legs. There are only six known extant species in the family, with four species of Trachypachus found in northern Eurasia and northern North America, and two species of Systolosoma in Chile and Argentina. They were much more diverse in the past, with dozens of described species from the Mesozoic.
The Cerophytidae are a family of beetles belonging to Elateroidea. Larvae are associated with rotting wood, on which they are presumed to feed. The family contains over 20 species in five genera, primarily distributed in the New World, but also in Eurasia and Africa. 17 fossil species in 7 genera are known extending to the Early Jurassic. Like some other elateroids, the adults are capable of clicking.
Bittacidae is a family of scorpionflies commonly called hangingflies or hanging scorpionflies.
Anaxyelidae is a family of incense cedar wood wasps in the order Hymenoptera. It contains only one living genus, Syntexis, which has only a single species, native to Western North America. Fossils of the family extend back to the Middle Jurassic, belonging to over a dozen extinct genera, with a particularly high diversity during the Early Cretaceous. Syntexis lay eggs in the sapwood of conifers, preferring recently burnt wood.
Priacma is a genus of beetles in the family Cupedidae. It contains a single extant species, Priacma serrata native to western North America and one fossil species, P. megapuncta from the Cenomanian aged Burmese amber. Species previously assigned to the genus from the Yixian Formation of China have been subsequently placed in the separate genus Apriacma.
Coptoclavidae is an extinct family of aquatic beetles in the suborder Adephaga. The Coptoclavidae lived from the Late Triassic to the Early Cretaceous. Coptoclavidae is a member of the adephagan clade Dytiscoidea, which contains other aquatic beetles. Suggested reasons for their extinction to include the rise of teleost fish, or competition with Gyrinidae and Dytiscidae, which possess defensive secretions and sucking channels in the mandibles of larvae, which coptoclavids likely lacked. It has been suggested that the genus Timarchopsis and the subfamily Timarchopsinae are only distantly related to other coptoclavids based on cladistic analysis, with Timarchopsis being more closely related to geadephagans like carabids and trachypachids instead. Another study also suggested similarly for Coptoclavisca and possibly other coptoclaviscines.
The Ommatidae are a family of beetles in the suborder Archostemata. The Ommatidae are considered the extant beetle family that has most ancestral characteristics. There are only seven extant species, confined to Australia and South America. However, the geographical distribution was much wider during the Mesozoic spanning across Eurasia and Australia, suggesting that they were widespread on Pangea. So far, over 26 extinct genera containing over 170 species of these beetles have been described. Three extant genera have been assigned to this family: Omma,Tetraphalerus and Beutelius. The family is considered to be a subfamily of Cupedidae by some authors, but have been found to be more closely related to Micromalthidae in molecular phylogenies. A close relationship with Micromalthidae is supported by several morphological characters, including those of the mandibles and male genitalia. Due to their rarity, their ecology is obscure, it is likely that their larvae feed on deadwood.
Brochocoleus is an extinct genus of beetles in the family Ommatidae, known from the Early Jurassic to the Early Late Cretaceous. 9 species are currently recognised, with many species being reassigned to other genera by Kirejtshuk's major systematic revision in 2020.
Zygadenia is an extinct genus of archostematan beetles from the Jurassic to Cretaceous. It is considered to be a senior synonym of Notocupes by Kirejtshuk (2020), but other researchers suggest to reserve the genus Zygadenia as a form taxon for isolated elytra that probably belong to the genus Notocupes, while retaining Notocupes as a valid genus for complete body fossils.
Cionocoleus is an extinct genus of beetles in the family Ommatidae.
Omma is a genus of beetles in the family Ommatidae. Omma is an example of a living fossil. The oldest species known, O. liassicum, lived during the final stage of the Triassic (Rhaetian), over 200 million years ago, though the placement of this species in Omma has been questioned. Numerous other fossil species are known from the Jurassic and Cretaceous of Europe and Asia. The only living species is Omma stanleyi, which is endemic to Australia. Three other extant species endemic to Australia that were formerly part of this genus were moved to the separate genus Beutelius in 2020.Omma stanleyi is strongly associated with wood, being found under Eucalyptus bark and exhibiting thanatosis when disturbed. Its larval stage and many other life details are unknown due to its rarity. Males are typically 14–20 mm in length, while females are 14.4-27.5 mm. Omma stanleyi occurs throughout eastern Australia from Victoria to Central Queensland.
Tetraphalerus is a genus of beetles in the family Ommatidae, It is currently known from two extant species native to South America and several fossil species from the Jurassic and Cretaceous of Asia.
Mesoraphidiidae is an extinct family of snakeflies in the suborder Raphidiomorpha. The family lived from the Late Jurassic through the Late Cretaceous and is known from twenty-five genera. Mesoraphidiids have been found as both compression fossils and as inclusions in amber. The family was first proposed in 1925 by the Russian paleoentomologist Andrey Vasilyevich Martynov based on Upper Jurassic fossils recovered in Kazakhstan. The family was expanded in 2002 by the synonymizing of several other proposed snakefly families. The family was divided into three subfamilies and one tribe in a 2011 paper, further clarifying the relationships of the included genera.
Blattulidae is an extinct family of cockroaches known from the Triassic to the Late Cretaceous. Their distinguishing characteristics include "forewing has long Sc, regular venation with distinct intercalaries and hindwing has simple CuP, branched A1."
Mesoblattinidae is an extinct, problematic family of cockroaches known from the Mesozoic. It was formerly considered a wastebasket taxon for Mesozoic cockroaches, but the family has subsequently been better defined, with many taxa transferred to Caloblattinidae. It is considered to have close affinities with Blattidae and Ectobiidae, as well as possibly Blaberidae. The family first appeared by the Early Jurassic. They are considered to represent amongst the oldest groups of modern cockroaches, and like them are thought to have laid oothecae.
Allophalerus is an extinct genus of beetle in the family Ommatidae. It is known from nine species formerly included in the genus Tetraphalerus.
Elcanidae are an extinct family of Mesozoic and early Cenozoic orthopterans. Members of the family are distinguished by the presence of spurs on the distal part of the metatibia, unique among orthopterans, these have been suggested to have been used for controlling gliding, swimming aids, or for jumping on water. The group combines characteristics from both major groups of orthopterans, with long antennae and nymphal morphology similar to Ensifera, but with wing venation and adult morphology more similar to Caelifera. Elcanidae is part of Elcanoidea, which is thought to have diverged from living orthopterans by the beginning of the Permian, around 300 million years ago. The family also includes Permelcanidae, known from the Early-Late Permian. The relationship of Elcanoidea to Ensifera and Caelifera is currently unresolved. Elcanids are known from the Late Triassic to Paleocene of Eurasia, North and South America. Some members of the group exhibited aposematic coloration.
Angarosphecidae is an extinct family of Mesozoic and early Cenozoic wasps in the superfamily Apoidea.
Mesochrysopidae is an extinct family of lacewings known from the Jurassic and Cretaceous periods. They are considered to be closely related to green lacewings of the family Chrysopidae. The family are also alternatively considered a paraphyletic grade leading up to crown Chrysopidae.
Notocupes is an extinct genus of medium-sized archostematan beetles from the Mesozoic Era of Eurasia, including over 50 described species. Historically, the genus was classified as a member of the family Ommatidae, but the presence of characters such as the horizontal mandibular cutting edge, separated procoxae and overlapping abdominal sternites indicate that the genus may have a closer affinity with the family Cupedidae. Notocupes is considered to be a junior synonym of Zygadenia by Kirejtshuk (2020), but other researchers suggest to reserve the genus Zygadenia as a form taxon for isolated elytra that probably belong to the genus Notocupes, while retaining Notocupes as a valid genus for complete body fossils. Most species of Notocupes were described from compression fossils. An additional three species were described from Cenomanian-aged Burmese amber, which were treated as a separate genus, Echinocups, by Kirejtshuk (2020), but Li et al. (2023) consider Echinocups to be a junior synonym of Notocupes. Notocupes has a flattened body, which may suggest that it occupied narrow habitats, such as living under bark. Some species had serrated/spined margins of the carapace, which may have served as a defense against predators, or served as camouflage to resemble bark.
