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.
The Ptychopteridae, phantom crane flies, are a small family of nematocerous Diptera. Superficially similar in appearance to other "tipuloid" families, they lack the ocelli of the Trichoceridae, the five-branched radial vein of the Tanyderidae, and the two anal veins that reach the wing margins of the Tipulidae. They are usually allied with the Tanyderidae based on similarities of the mesonotal suture, this group being called the Ptychopteromorpha.
The Tettigarctidae, known as the hairy cicadas, are a small relict family of primitive cicadas. Along with more than 20 extinct genera, Tettigarctidae contains a single extant genus, Tettigarcta, with two extant species, one from southern Australia and one from the island of Tasmania. Numerous fossil species have been described from the Late Triassic onwards. Tettigarcta are the closest living relatives of the true cicadas.
Osmylidae are a small family of winged insects of the net-winged insect order Neuroptera. The osmylids, also called lance lacewings, stream lacewings or giant lacewings, are found all over the world. There are around 225 extant species.
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 Progonocimicidae are an extinct family of true bugs in the suborder Coleorrhyncha. Progonocimicidae fossils have been found in Europe, Asia, Australia, and South America.
Locustopsidae is an extinct family of grasshoppers in the order Orthoptera. There are about 17 genera and more than 60 described species in Locustopsidae.
Pseudopolycentropodidae is an extinct family of scorpionflies known from the Mesozoic. Fossils are known from the Middle Triassic (Anisian) to the early Late Cretaceous (Cenomanian). It is part of Mesopsychoidea, a group of scorpionflies with siphonate proboscis. They are suggested to have been nectarivores, feeding off the liquid pollination drops and acting as pollinators for now extinct insect pollinated gymnosperms such as Bennettitales.
Mesopsychidae is an extinct family of scorpionflies known from the Late Permian to Mid Cretaceous. It is part of Mesopsychoidea, a group of scorpionflies with siphonate proboscis. They are suggested to have been nectarivores, feeding off the liquid pollination drops and acting as pollinators for now extinct insect pollinated gymnosperms such as Bennettitales.
Dermapteridae is an extinct family of earwigs known from the Late Triassic to Mid Cretaceous, it is part of the extinct suborder Archidermaptera, alongside Protodiplatyidae and Turanovia. It was first named as a subfamily by Vishniakova in 1980, and elevated to family status by Engel in 2003 without discussion.
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 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.
Archijassidae is an extinct family of leafhoppers known from the Late Triassic to the early Late Cretaceous. It is the oldest member of Membracoidea, and is considered ancestral to modern leaf and treehoppers.
Procercopidae is an extinct family of froghoppers. They are known from the Early Jurassic to early Late Cretaceous of Eurasia. They are one of two main families of Mesozoic froghoppers alongside Sinoalidae. Procercopidae are considered to be the ancestral group from which modern froghoppers are derived.
Fulgoridiidae are an extinct family of Mesozoic planthoppers. They are the earliest group of planthoppers known, and appear to be a paraphyletic assemblage ancestral to living planthoppers. The majority of known members of the family lived in the Jurassic period, though the group also includes one Cretaceous taxon. All currently known species are from Eurasia.
Necrotauliidae is an extinct family Mesozoic Amphiesmenoptera. While previously considered a paraphyletic grouping of "basal Trichoptera, basal Lepidoptera, and advanced stem-Amphiesmenoptera", they have recently been considered early diverging caddisflies. Other authors have considered them to be basal amphiesiopterans.
Protorthophlebia is an extinct genus of scorpionflies, known from the Triassic and Jurassic periods of Eurasia. It was originally considered a member of the family Orthophlebiidae, but was later placed as the only genus within the family Protorthophlebiidae within the superfamily Panorpoidea.
Geinitziidae is an extinct family of polyneopteran insects, known from the Permian to Cretaceous. They are currently considered to be members "Grylloblattida" a poorly defined group of extinct insects thought to be related to modern ice crawlers (Grylloblattidae). Other authors place them in the extinct order Reculida. Unlike modern ice crawlers, which are wingless, they had large wings, bearing a superficial resemblance to cockroaches, and are thought to have been day-active above ground predators.
