The Mygalomorphae, or mygalomorphs, are an infraorder of spiders, and comprise one of three major groups of living spiders with over 3,000 species, found on all continents except Antarctica. Many members are known as trapdoor spiders due to their creation of trapdoors over their burrows. Other prominent groups include Australian funnel web spiders and tarantulas, with the latter accounting for around one third of all mygalomorphs.
The family Dipluridae, known as curtain-web spiders are a group of spiders in the infraorder Mygalomorphae, that have two pairs of booklungs, and chelicerae (fangs) that move up and down in a stabbing motion. A number of genera, including that of the Sydney funnel-web spider (Atrax), used to be classified in this family but have now been moved to Atracidae.
Atracidae is a family of mygalomorph spiders, commonly known as Australian funnel-web spiders or atracids. It has been included as a subfamily of the Hexathelidae, but is now recognised as a separate family. All members of the family are native to Australia. Atracidae consists of three genera: Atrax, Hadronyche, and Illawarra, comprising 35 species. Some members of the family produce venom that is dangerous to humans, and bites by spiders of six of the species have caused severe injuries to victims. The bites of the Sydney funnel-web spider and northern tree-dwelling funnel-web spider are potentially deadly, but no fatalities have occurred since the introduction of modern first-aid techniques and antivenom.
Ctenizidae is a small family of mygalomorph spiders that construct burrows with a cork-like trapdoor made of soil, vegetation, and silk. They may be called trapdoor spiders, as are other, similar species, such as those of the families Liphistiidae, Barychelidae, and Cyrtaucheniidae, and some species in the Idiopidae and Nemesiidae. The name comes from the distinctive behavior of the spiders to construct trapdoors, and ambush prey from beneath them.
Atrax is a genus of venomous Australian funnel web spiders that was first described by O. Pickard-Cambridge in 1877 from the type species Atrax robustus. As of May 2019 it contains only three species: A. robustus, A. sutherlandi, and A. yorkmainorum. Originally placed with the curtain web spiders, it was moved to the Hexathelidae in 1980, then to the Australian funnel-web spiders in 2018.
Actinopus is a genus of mygalomorph spiders in the family Actinopodidae. It was first described by Josef Anton Maximilian Perty in 1833 from the type species Actinopus tarsalis found in Brazil. The name is derived from Greek actin- "ray, beam" and pous "foot". It is a senior synonym of Aussereria, Closterochilus, Pachyloscelis, and Theragretes.
Plesiolena is a small genus of South American mygalomorph spiders in the family Actinopodidae. It was first described by Pablo A. Goloboff and Norman I. Platnick in 1987, and it has only been found in Chile. The name is a combination of "plesiomorphy" and the genus Missulena. As of November 2021 it contains only 2 species: P. bonneti and P. jorgelina.
Barychelidae, also known as brushed trapdoor spiders, is a spider family with about 300 species in 42 genera.
Antrodiaetidae, also known as folding trapdoor spiders or folding-door spiders, is a small spider family related to atypical tarantulas. They are found almost exclusively in the western and midwestern United States, from California to Washington and east to the Appalachian mountains. Exceptions include Antrodiaetus roretzi and Antrodiaetus yesoensis, which are endemic to Japan and are considered relict species. It is likely that two separate vicariance events led to the evolution of these two species.
Sason is a genus of bark-dwelling brushed trapdoor spiders first described by Eugène Simon in 1887. It is distributed from the Seychelles through India to northern Australia. The closest related genus seems to be the monotypic Paracenobiopelma.
Stanwellia is a genus of South Pacific mygalomorph spiders in the family Pycnothelidae. It was first described by W. J. Rainbow & R. H. Pulleine in 1918. Originally placed with the curtain-web spiders, it was transferred to the funnel-web trapdoor spiders in 1985, then to the Pycnothelidae in 2020. It is a senior synonym of Aparua.
Porrhothele is a genus of mygalomorph spiders endemic to New Zealand. They are the only members of the family Porrhothelidae. They were first described by Eugène Louis Simon in 1892. Originally placed with the curtain web spiders, it was moved to the Hexathelidae in 1980, they were placed in their own family in 2018.
Aliatypus is a genus of North American folding trapdoor spiders first described by C. P. Smith in 1908. They resemble members of Ctenizidae in morphology and behavior, but this is due to convergent evolution rather than direct relation. They are most closely related to members of Antrodiaetus, which build collar doors. It is likely that the shift from using collar doors to using trapdoors is what allowed them to survive in hot, dry conditions where their closest relatives could not.
Atypoides riversi, known as turret spider, is a species of mygalomorph spider in the family Antrodiaetidae. It is a medium-sized spider native to Northern California that constructs a burrow with a turret made of soil, vegetation and silk. This spider's length is 13 to 18 millimetres long, though females are larger than males.
Eucteniza is a genus of trapdoor spiders in the family Euctenizidae containing at least 14 species occurring in Mexico and the southern United States. Species are distinguished by a softened rear portion of the carapace, and males possess large spines on the first two pairs of walking legs that are used to hold females during mating. Like other trapdoor spiders they create burrows with a hinged lid, from which they await passing insects and other arthropods to prey upon. Many species are known from only one or two localities, or from only male specimens. More species are expected to be discovered. Eucteniza is closely related to spiders of the genera Entychides and Neoapachella.
Apomastus is a genus of North American mygalomorph spiders in the family Euctenizidae, and was first described by Jason Bond & B. D. Opell in 2002. As of May 2019 it contains only two species, both found in the Los Angeles Basin of southern California: A. kristenae and A. schlingeri.
Hexura is a genus of American folding trapdoor spiders that was first described by Eugène Louis Simon in 1884. As of September 2019 it contains two species, found in the United States: H. picea and H. rothi. Originally placed with Mecicobothriidae, it was moved to Antrodiaetidae in 2019.
Holothele is a genus of tarantulas that was first described by Ferdinand Anton Franz Karsch in 1879. Originally placed with the curtain-web spiders, it was transferred to the tarantulas in 1980.
Pionothele is a genus of African mygalomorph spiders in the family Pycnothelidae. It was first described by William Frederick Purcell in 1902. As of June 2020 it contains 2 species, found in Namibia and South Africa: P. gobabeb, and P. straminea. Originally placed with the Ctenizidae, it was transferred to the funnel-web trapdoor spiders in 1985, then to the Pycnothelidae in 2020.
Antrodiaetus pacificus is a species of mygalomorph spiders native to the Pacific Northwest. Both male and female were first described by French arachnologist Eugène Louis Simon in 1884 under the name Brachybothrium pacificum. The genus name is a combination of the Greek "antrodiaitos" (αντροδιαιτος), meaning "living in caves", "antron" (αντρον), meaning "cave", and "diaita (διαιτα), meaning "way of life, dwelling". The specific epithet refers to its geographical distribution along the pacific coast of North America, between San Francisco Bay and Alaska. It is the northernmost mygalomorph spider in North America.
