Mygalomorphae
Guides
Antrodiaetus lincolnianus
Lincoln's folding-door spider
Antrodiaetus lincolnianus is a species of folding-door spider in the family Antrodiaetidae, originally described as Brachybothrium lincolnianum by Worley in 1928. As a mygalomorph spider, it constructs a burrow sealed with a hinged, silken door that it uses for protection and ambush predation. The species is endemic to the United States. Like other members of the Antrodiaetus unicolor species complex, it has been subject to recent taxonomic revision using molecular methods due to cryptic morphological similarity with closely related species.
Aphonopelma anax
Texas tan tarantula
Aphonopelma anax, the Texas tan tarantula, is among the largest tarantula species in the United States, with mature individuals reaching leg spans of 5–6 inches. The species exhibits pronounced sexual dimorphism: females are larger-bodied with shorter legs and can live up to 40 years, while males have longer legs, smaller bodies, and typically survive less than two years after maturity. Males abandon their burrows during the late summer and early fall mating season to actively search for sedentary females, traveling up to 1.2 km in a single night and covering areas up to 29 hectares. The species employs behavioral thermoregulation, retreating into temporary burrows during daytime heat and emerging in the evening when thermal conditions permit sustained activity.
Aphonopelma vorhiesi
Tucson Bronze Tarantula, Madrean Red Rump
Aphonopelma vorhiesi is a tarantula species in the family Theraphosidae, commonly known as the Tucson Bronze or Madrean Red Rump. It occurs in Arizona and New Mexico. The species resembles Aphonopelma chalcodes but is considerably rarer in captivity. Like other Aphonopelma species, it is a ground-dwelling spider that constructs and occupies burrows.
Aptostichus chemehuevi
Chemehuevi Desert Trapdoor Spider
Aptostichus chemehuevi is a species of trapdoor spider in the family Euctenizidae, described by arachnologist Jason Bond in 2012. It belongs to a genus of mygalomorph spiders known for constructing silk-lined burrows with hinged trapdoor lids. The species epithet references the Chemehuevi people, a Native American group whose traditional territory includes parts of the southwestern United States where this spider occurs. Like other Aptostichus species, it is a fossorial predator with limited dispersal capability.
Atypidae
purseweb spiders, atypical tarantulas
Atypidae is a family of mygalomorph spiders commonly known as purseweb spiders or atypical tarantulas. The family contains only three genera and represents one of the most archaic spider lineages. Members are obligate burrowers that construct distinctive sock-like, silken tubes extending from underground burrows up vertical surfaces. They are ambush predators that rarely leave their retreats, instead detecting and capturing prey from within their webs. The family has a disjunct distribution across Eurasia, northern Africa, and North America, with most species in the genus Atypus.
Eucteniza relata
Southwestern Trapdoor Spider
Eucteniza relata, commonly known as the southwestern trapdoor spider, is a species of wafer-lid trapdoor spider in the family Euctenizidae. It is found in the United States and Mexico. The species belongs to a family of mygalomorph spiders known for constructing burrows with trap doors made of soil, vegetation, and silk.
Myrmekiaphila
Ant-loving trapdoor spiders
Myrmekiaphila is a genus of mygalomorph trapdoor spiders in the family Euctenizidae, endemic to the southeastern United States. The genus was first described by G.F. Atkinson in 1886 and has undergone several taxonomic revisions, most recently placed in Euctenizidae in 2012. These spiders construct subterranean silk-lined burrows with silken-soil trap doors, and some species uniquely build side chambers closed by secondary trap doors. The genus name derives from Greek roots meaning 'ant-loving,' referencing their frequent association with ant nests.
Theraphosidae
tarantulas, bird spiders, birdeaters
Theraphosidae is a family of large, often hairy spiders commonly known as tarantulas. The family comprises approximately 900 described species distributed across tropical, subtropical, and arid regions worldwide. Tarantulas are characterized by their substantial size, with some species reaching leg spans up to 30 cm, and their longevity—females of certain species can live 20 to 30 years. They are primarily nocturnal predators that employ diverse hunting strategies including ambush from burrows, active pursuit, and arboreal hunting. The family exhibits considerable ecological diversity, with species occupying terrestrial burrowing, arboreal, and even cave-dwelling niches.