Crevice weaver spiders (Filistatidae) comprise cribellate spiders with features that have been regarded as "primitive" for araneomorph spiders. They are weavers of funnel or tube webs. The family contains 18 genera and more than 120 described species worldwide.
Leptonetidae is a relatively primitive family of spiders first described by Eugène Simon in 1890. It is made up of tiny haplogyne spiders, meaning they lack the hardened external female genitalia. Their six eyes are arranged in a semicircle of four in front and two behind. Many live in caves or in leaf litter around the Mediterranean, and in Eurasia, Japan and southern North America.
Neoleptoneta is a genus of North American leptonetids that was first described by Paolo Marcello Brignoli in 1972.
The Haplogynae or haplogynes are one of the two main groups into which araneomorph spiders have traditionally been divided, the other being the Entelegynae. Morphological phylogenetic studies suggested that the Haplogynae formed a clade; more recent molecular phylogenetic studies refute this, although many of the ecribellate haplogynes do appear to form a clade, Synspermiata.
Texella reddelli, the Bee Creek cave harvestman, is a rare species of troglobitic harvestman that was added to the United States endangered species list in 1988, at the same time as six other species native to the karst ecosystem in Travis County and Williamson County, Texas, USA. They inhabit areas with near 100% humidity and constant temperatures, and they prey on springtails. Since they can only be found underground, research on these creatures has been difficult. Their distribution is limited and unknown reproductive rates mean that it is possible they are especially susceptible to habitat destruction and other threats. Texella reddelli are found on both the North and South sides of the Colorado River.
The Kretschmarr Cave mold beetle is a small mold beetle.
The Cokendolpher cave harvestman, Texella cokendolpheri, is a species of cave-living harvestman native to Bexar County, Texas. The original common name, the Robber Baron Cave harvestman, stemmed from the cave which the harvestman inhabits. The scientific name and the current common name honor the prominent arachnologist, James Cokendolpher, who identified the species. T. cokendolpheri is one of twenty-eight species within the North American harvestman genus Texella. The first formal description of the harvestman took place in 1992 and the species’ listing under the Endangered Species Act followed eight years later. Current threats to the species include habitat loss and interactions with invasive fire ants.
Cicurina madla is a rare species of spider in the family Dictynidae known by the common name Madla Cave meshweaver. It is endemic to Texas, United States, where it is known to originate from only eight or nine caves in Bexar County. This is one of a small number of invertebrates endemic to the karst caves of Bexar County that were federally listed as endangered species in the year 2000. Another spider from the caves was described as Cicurina venii, and given the common name Braken Bat Cave meshweaver. In 2018, it was synonymized with C. madla.
Trogloraptor is a genus of large spiders found in the caves of southwestern Oregon. It is the sole genus in the family Trogloraptoridae, and includes only one species, Trogloraptor marchingtoni. These spiders are predominantly yellow-brown in color with a maximum leg span of 3 in (7.6 cm). They are remarkable for having hook-like claws on the raptorial last segments of their legs.
Calileptoneta is a genus of North American Leptonetids that was first described by Norman I. Platnick in 1986.
Chisoneta is a genus of North American Leptonetids that was first described by J. Ledford in 2011.
Darkoneta is a genus of spiders that was first described by J. M. Ledford & C. E. Griswold in 2010.
Montanineta is a monotypic genus of North American leptonetid spiders containing the single species, Montanineta sandra. It was first described by J. Ledford in 2011, and has only been found in the United States.
Ozarkia is a genus of North American leptonetids that was first described by J. Ledford in 2011.
Tayshaneta is a genus of North American leptonetids that was first described by J. Ledford in 2011.
Apollophanes is a genus of running crab spiders that was first described by Octavius Pickard-Cambridge in 1898.
Clubiona pallidula is a species of sac spider in the family Clubionidae. It is found in Europe, Caucasus, a range from Russia to Central Asia, and has been introduced into North America.
Archoleptonetidae is a family of spiders in the order Araneae. There are two genera and about eight described species in Archoleptonetidae. They are known from the western USA, southern Mexico, Guatemala, and Panama. This family was formerly a subfamily of Leptonetidae.
Tayshaneta microps, synonym Neoleptoneta microps, is a rare species of spider in the family Leptonetidae known by the common name Government Canyon bat cave spider. It is endemic to Texas in the United States, where it is known to be found in two caves in Bexar County. It is a troglobite, an animal which spends its entire life in caves. It is one of nine Bexar County troglobites which were listed as endangered species in 2000.
