Mygalomorph
Guides
Microhexura
Pygmy Funnel-web Spiders, spruce-fir moss spider (M. montivaga)
Microhexura is a genus of minute mygalomorph spiders endemic to North America, containing two described species: M. montivaga and M. idahoana. The genus represents the sole member of family Microhexuridae. M. montivaga, the spruce-fir moss spider, is restricted to high-elevation spruce-fir forests on isolated peaks in the southern Appalachians and is federally endangered. M. idahoana occurs in old-growth coniferous forests of the Pacific Northwest and northern Rocky Mountains. Both species inhabit moss mats and are among the smallest mygalomorph spiders.
Microhexura idahoana
Microhexura idahoana is a mygalomorph spider described in 1945 from Idaho. It is one of only two species in the genus Microhexura, and the sole member of the family Microhexuridae. The species is known from a limited number of observations in the western United States.
Microhexura montivaga
Spruce-fir moss spider
A miniature mygalomorph spider endemic to the highest peaks of the southern Appalachian Mountains. First described in 1925, this species inhabits moss growing on rocks beneath spruce-fir forest canopy. Listed as federally endangered in 1995 due to severe declines in its montane forest habitat. Genetic studies reveal significant population fragmentation across six allopatric populations, though morphological differences remain minimal.
Myrmekiaphila comstocki
Comstock's Wafer Trapdoor Spider
Myrmekiaphila comstocki is a trapdoor spider in the family Euctenizidae, commonly known as the wafer-lid trapdoor spiders. It belongs to the infraorder Mygalomorphae, a group of ancient spiders that includes tarantulas and funnel-web spiders. The species constructs silk-lined burrows with hinged, wafer-like trapdoors. Its distribution spans the United States and Mexico.
Nemesiidae
Tubetrapdoor and Wishbone Spiders, wishbone spiders
Nemesiidae is a family of mygalomorph spiders first described by Eugène Simon in 1889 and elevated to family status in 1985, having previously been considered part of Dipluridae. The family comprises relatively large, darkly colored spiders with elongated bodies and robust legs, commonly known as wishbone spiders due to the distinctive shape of their burrows. Members are primarily fossorial, constructing silk-lined burrows often equipped with hinged trapdoors for ambush predation. The family includes ten genera and approximately 195 species distributed across diverse habitats including coastal sands, forests, and mountainous regions on multiple continents.
Neoapachella rothi
Neoapachella rothi is a mygalomorph trapdoor spider and the sole species in its genus. It was described in 2002 and is endemic to the southwestern United States. The species name honors arachnologist Vincent D. Roth, while the genus name references the Apache peoples. Adults reach approximately 20.7 mm in body length.
Promyrmekiaphila
Promyrmekiaphila is a genus of mygalomorph trapdoor spiders endemic to California. First described by Schenkel in 1950, the genus currently contains three species: P. clathrata, P. winnemem, and P. korematsui. These spiders construct silk-lined burrows with wafer-like trapdoor lids and exhibit strong geographic population structuring with deep genetic divergence, particularly within P. clathrata. The genus is notable for morphological conservation despite considerable genetic differentiation, representing a cryptic species complex.
Promyrmekiaphila clathrata
wafer-lid trapdoor spider
Promyrmekiaphila clathrata is a species of wafer-lid trapdoor spider in the family Euctenizidae, endemic to California. It constructs silk-lined burrows up to 30 cm deep in soil, covered with a wafer-like trapdoor made of silk and soil. The species exhibits deep genetic population structure across its range but is not divided into multiple species. It is one of three described species in the genus Promyrmekiaphila.
Sphodros
purseweb spiders
Sphodros is a genus of mygalomorph spiders in the family Atypidae, native to North America. The genus was reinstated in 1980 after being treated as a synonym of Atypus for over a century. Seven species are recognized, distributed across the United States, Canada, and Mexico. These spiders are known for constructing distinctive purse-shaped webs attached to tree trunks and root systems.
Sphodros niger
Black purse-web spider, Black Purseweb Spider
Sphodros niger is a mygalomorph spider native to northeastern North America. Males reach approximately 11 mm in body length (29 mm with legs extended) and possess distinctive chocolate-brown legs contrasting with an otherwise black body. Females were not described until 1980, 138 years after the species was first named, due to their sedentary tube-dwelling behavior. The species is listed as a special concern species in Connecticut and ranked as vulnerable in Virginia.
Sphodros rufipes
Red-legged Purseweb Spider
Sphodros rufipes is a mygalomorph spider in the purseweb spider family Atypidae, native to eastern and southern North America. First described as Atypus rufipes by Latreille in 1829, it was transferred to the genus Sphodros in 1980. The species is notable for its distinctive hunting strategy using a silk tunnel constructed against trees or other objects, and for the pronounced sexual dimorphism in leg coloration. Females have been documented living up to 7 years.
Tliltocatl
Red Rump Tarantula (for T. vagans)
Tliltocatl is a genus of large burrowing tarantulas in the family Theraphosidae, erected in 2020 when molecular phylogenetic studies demonstrated that the genus Brachypelma comprised two distinct clades. Species are found predominantly in Mexico and Central America. The genus name derives from Nahuatl words meaning 'black spider.' Unlike Brachypelma species, Tliltocatl lacks striking red leg markings, instead displaying more subdued coloration with long red or yellowish abdominal hairs. Several species are threatened by habitat destruction and collection for the pet trade, leading to CITES protection.