Sicarius (spider)
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Six-eyed sand spiders |
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Six-eyed sand spider
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see article |
Sicarius is a genus of venomous spiders, the best known being the six-eyed sand spider of southern Africa.
Contents |
[edit] Habitat and appearance
Sicarius are desert spiders that live in the Southern Hemisphere, in (South America and Africa), known primarily for their self-burying behavior. All have six eyes arranged in three groups of two (diads). Sicarius resembles the crab spiders of the family Thomisidae and lacks the characteristic violin-shaped marking of their cousins, the recluse spiders. Individual Sicarius can live for as much as 15 years, which makes these among the longest-lived araneomorphae spiders (some tarantulas can live well over 20-30 years), and can live for very long times without food or water.
[edit] Venom components and effects
The spiders of this genus (along with the recluse spiders) have potent tissue-destroying venoms containing the dermonecrotic agent, sphingomyelinase D, which is otherwise found only in a few pathogenic bacteria. This venom is highly necrotic in effect, capable of causing lesions (open sores) as large as a US quarter. The genus Sicarius may have more toxic venom than Loxosceles (particularly the African species), based on laboratory experiments with rabbits. Sicariids are found in such barren deserts and are able to bury themselves partially in the sand, that humans seldom come in contact with them. The females produce egg sacs covered with a mixture of sand and silk. The genus is considered to be a living fossil in that it is both quite primitive and distributed in parts of the former Gondwanaland, the huge southern continent that separated during the Mesozoic. One example of this genus is the six-eyed sand spider, S. hahni, whose bite is capable of major systemic damage (and is often deadly). However, bites by this spider are rare.
A U.S. patent (number 6,998,389) has been awarded for a means for using Sicariidae venom as a treatment for cancer. [1]
[edit] Species
- Sicarius albospinosus Purcell, 1908 (South Africa)
- Sicarius crustosus (Nicolet, 1849) (Chile)
- Sicarius damarensis Lawrence, 1928 (Namibia)
- Sicarius deformis (Nicolet, 1849) (Chile)
- Sicarius dolichocephalus Lawrence, 1928 (Namibia)
- Sicarius fumosus (Nicolet, 1849) (Chile)
- Sicarius gracilis (Keyserling, 1880) (Peru)
- Sicarius hahni (Karsch, 1878) (Namibia)
- Sicarius lanuginosus (Nicolet, 1849) (Chile)
- Sicarius minoratus (Nicolet, 1849) (Chile)
- Sicarius nicoleti (Keyserling, 1880) (Chile)
- Sicarius patagonicus Simon, 1919 (Argentina)
- Sicarius peruensis (Keyserling, 1880) (Peru)
- Sicarius rubripes (Nicolet, 1849) (Chile)
- Sicarius rugosus (F. O. P.-Cambridge, 1899) (El Salvador, Costa Rica)
- Sicarius rupestris (Holmberg, 1881) (Argentina)
- Sicarius spatulatus Pocock, 1900 (South Africa)
- Sicarius terrosus (Nicolet, 1849) (Chile, Argentina, Peru)
- Sicarius terrosus yurensis Strand, 1908 (Peru)
- Sicarius testaceus Purcell, 1908 (South Africa)
- Sicarius tropicus (Mello-Leitão, 1936) (Brazil)
- Sicarius utriformis (Butler, 1877) (Galapagos Is.)
[edit] See also
- List of Sicariidae species
- Spider families
- For pictures of many kinds of spiders, see The Spider Gallery
[edit] External links
- Arachnology Home Pages: Loxosceles: Recluse spiders
- Biodiversity Explorer: Family Sicariidae (Beautiful photos of Sicarius and Loxosceles)
- Platnick, N.I. 2003. World Spider Catalog.
- Vetter, R. 2003. Causes of Necrotic Wounds other than Brown Recluse Spider Bites.
- Vetter, R. 2003. Myth of the Brown Recluse Fact, Fear, and Loathing.
- Pictures of the Brown Recluse Spider