The Tooth Cave spider, formerly ''Neoleptoneta myopica'', now ''Tayshaneta myopica'', is a long

spider Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...

in the family

Leptonetidae 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 f ...

. It is endemic to limestone caves near

Austin, Texas Austin is the capital city of the U.S. state of Texas, as well as the county seat, seat and largest city of Travis County, Texas, Travis County, with portions extending into Hays County, Texas, Hays and Williamson County, Texas, Williamson co ...

in the United States and is considered an

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

Taxonomy

The Tooth Cave spider was first described in 1974 by

Willis J. Gertsch Willis John Gertsch (October 4, 1906 – December 12, 1998) was an American arachnologist. He described over 1,000 species of spiders, scorpions, and other arachnids, including the Brown recluse spider and the Tooth cave spider. Gertsch was born ...

, as ''Leptoneta myopica''. At the time it was only known from Tooth Cave in

Travis County, Texas Travis County is located in south central Texas. As of the 2020 census, the population was 1,290,188. It is the fifth-most populous county in Texas. Its county seat is Austin, the capital of Texas. The county was established in 1840 and is na ...

, 15 miles northwest of

Austin Austin is the capital city of the U.S. state of Texas, as well as the seat and largest city of Travis County, with portions extending into Hays and Williamson counties. Incorporated on December 27, 1839, it is the 11th-most-populous city ...

. The specific name ''myopica'' is from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''myopia'', "nearsighted". In 1977,

Paolo Brignoli Paolo Marcello Brignoli (25 April 1942 – 8 July 1986) was a prominent Italian entomologist. He studied a broad range of arachnid groups, including Araneidae, Acari, Ricinulei, Palpigradi, Schizomida, Opiliones, and Amblypygi. His research mainly ...

transferred the species to the genus '' Neoleptoneta''. A 2011

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

study of ''Neoleptoneta'' and other North American genera in the family

showed that ''Neoleptoneta'' was not

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

. Several new genera were erected, including ''

Tayshaneta ''Tayshaneta'' is a genus of North American leptonetids that was first described by J. Ledford in 2011. Species it contains nineteen species, all found in the United States: *''Tayshaneta anopica'' ( Gertsch, 1974) – USA *'' Tayshaneta archa ...

'', to which the Tooth Cave spider was transferred, as ''Tayshaneta myopica''.

Description

''Tayshaneta myopica'' is a small spider, about in total body length. Relative to its body, it has long legs: the first leg, the longest, is about , the third leg, the shortest, about . It is generally whitish in color with some yellower parts. It has six eyes, a group of four at the front and two behind. The eyes were initially described as "obsolescent" and without dark pigment. Later it was discovered that the species occurs in a range of forms, from depigmented, blind individuals to darkly pigmented, large-eyed individuals. Little is known of the life history of any of the species in the family Leptonetidae.

Distribution and habitat

In 2012, ''Tayshaneta myopica'' was known from caves in

Travis County Travis County is located in south central Texas. As of the 2020 census, the population was 1,290,188. It is the fifth-most populous county in Texas. Its county seat is Austin, the capital of Texas. The county was established in 1840 and is na ...

and Williamson County to the northwest of

. Six locations were given on a distribution map for the species, although precise details of the locations have not been given, partly for conservation reasons. The caves occur in

Edward's Plateau The Edwards Plateau is a geographic region at the crossroads of Central, South, and West Texas. It is bounded by the Balcones Fault to the south and east, the Llano Uplift and the Llano Estacado to the north, and the Pecos River and Chihuahuan ...

, a

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

karst Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...

") region of Central Texas. ''Tayshaneta'' spiders appear to spend most of their lives in their web, except for mature males. However, individuals of ''T. myopica'' from four nearby caves (Tooth Cave, Root Cave, Gallifer Cave and Tight Pit) have been shown to have identical

mitochondrial A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is use ...

and

nuclear DNA Nuclear DNA (nDNA), or nuclear deoxyribonucleic acid, is the DNA contained within each cell nucleus of a eukaryotic organism. It encodes for the majority of the genome in eukaryotes, with mitochondrial DNA and plastid DNA coding for the rest. It ...

haplotype A haplotype ( haploid genotype) is a group of alleles in an organism that are inherited together from a single parent. Many organisms contain genetic material ( DNA) which is inherited from two parents. Normally these organisms have their DNA or ...

s, suggesting that movement between the sites does take place. Individuals were seen suspended beneath low sheet webs, from which they dropped when disturbed.

Conservation

''Tayshaneta myopica'' was listed under the U.S. Endangered Species Act in 1988 because of its very limited distribution in an area outside of Austin, Texas, that is rapidly urbanizing. Conservation efforts have been focused on "karst faunal regions".

References

{{Taxonbar, from=Q2218374 Leptonetidae Spiders of the United States Endemic fauna of Texas Cave spiders Endangered fauna of the United States ESA endangered species Taxa named by Willis J. Gertsch Taxobox binomials not recognized by IUCN

Taxonomy

Description

Distribution and habitat

Conservation

See also

References