Linothele

Linothele
L. fallax
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Mygalomorphae
Family:	Dipluridae
Genus:	Linothele Karsch, 1879[1]
Type species
L. curvitarsis Karsch, 1879
Species
63, see text
Synonyms[1][2]
Uruchus Simon, 1889

Linothele is a genus of curtain web spiders that was first described by Ferdinand Karsch in 1879.^[3] All but one of the described species are from South America (Bolivia, Brazil, Colombia, Ecuador, Peru and Venezuela). The exception is L. septentrionalis from the far-away Bahamas, although it has certain features that suggest it may belong in another genus.^[4] Additionally, an undescribed species of Linothele is known from Panama.^[5]

Linothele females are stouter and tend to be more conspicuously colored than males.^[4] They make relatively complex webs that in most species are on or near the ground, mudbanks or rock walls (a few are arboreal), with females spending most of their life in a tunnel-like retreat. The male may wander and often inhabits a smaller web near a female's.^[4] The webs of Linothele are commonly co-inhabited by tiny kleptoparasitic spiders of the genus Mysmenopsis.^[4]

Venom

In humans, bites from Linothele typically cause mild pain and a numbness/tingling feeling that can last for a few days.^[4] They are generally reluctant to bite and will attempt to flee, but some species, especially those from dry regions, tend to be more defensive.^[4]

The venom of Linothele sp has a LD-50 dose of 0.6 mg/kg in laboratory mice. Two toxins, both of low molecular weight, were isolated in the venom, Ls1 and Ls2. These two toxins have been shown to be quite lethal to laboratory mice by injection into the cerebroventricular region. The lethal dose of Ls1 and Ls2 is 24 and 19 μg/kg respectively, both toxins represent 0.21% and 0.43% of the weight of the whole venom.^[6]

Species

As of July 2023^[update] it contains 63 species:^[1]

References