Sicarius (genus)

Taxobox
name = Six-eyed sand spiders


image_width = 200px
image_caption = Six-eyed sand spider
regnum = Animalia
phylum = Arthropoda
classis = Arachnida
ordo = Araneae
familia = Sicariidae
genus = Sicarius
genus_authority = Walckenaer, 1847
diversity_link = List of Sicariidae species#Sicarius
diversity = 21 species
subdivision_ranks = Species
subdivision = see article

Sicarius is a genus of venomous spiders, the best known being the six-eyed sand spider of southern Africa.

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 the members of the family Homalonychidae. However, Sicarius 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.

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 barren deserts and are able to bury themselves partially in the sand. Because of this, 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 deadlyFact|date=February 2008). 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. [http://www.pharmcast.com/Patents100/Yr2006/Feb2006/021406/6998389_Spider021406.htm]

pecies

* "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.)

ee also

* List of Sicariidae species
* Spider families

External links

* [http://www.arachnology.org/Arachnology/Pages/Reclusa.html Arachnology Home Pages: Loxosceles: Recluse spiders]
* [http://www.museums.org.za/bio/spiderweb/sicariid.htm Biodiversity Explorer: Family Sicariidae] (Beautiful photos of "Sicarius" and "Loxosceles")
* [http://research.amnh.org/entomology/spiders/catalog81-87/index.html Platnick, N.I. 2003. World Spider Catalog.]
* [http://spiders.ucr.edu/necrotic.html Vetter, R. 2003. Causes of Necrotic Wounds other than Brown Recluse Spider Bites.]
* [http://spiders.ucr.edu/myth.html Vetter, R. 2003. Myth of the Brown Recluse Fact, Fear, and Loathing.]
* [http://www.spiderpicturesandinfo.com/brown-recluse-spider/ Pictures of the Brown Recluse Spider]