Latrodectus hesperus
| Latrodectus hesperus | |
|---|---|
 |
|
| Latrodectus hesperus female | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Arachnida |
| Order: | Araneae |
| Family: | Theridiidae |
| Genus: | Latrodectus |
| Species: | L. hesperus |
| Binomial name | |
| Latrodectus hesperus Chamberlin & Ivie, 1935[1] |
|
Latrodectus hesperus, the Western black widow spider or Western widow, is a venomous spider species found in western regions of North America. The female's body is 14–16 millimeters in length and is black, often with an hourglass shaped red mark on the lower abdomen. This "hourglass" mark can be yellow, and on rare occasions, white. The male of the species is around half this size and generally a tan color with lighter striping on the abdomen. The population was previously described as a subspecies of Latrodectus mactans and it is closely related to the northern species Latrodectus variolus. The species, as with others of the genus, build irregular webs.
The female's consumption of the male after courtship, a cannibalistic and suicidal behaviour observed in Latrodectus hasseltii (Australia's redback),[2] is rare in this species. Male Western widows may breed several times during their relatively short lifespans.[3]
The ultimate strength and other physical properties of Latrodectus hesperus silk were found to be similar to the properties of silk from orb weaving spiders that had been tested in other studies. The ultimate strength for the three kinds of silk measured in the Blackledge study was about 1000 MPa. The ultimate strength reported in a previous study for Nephila edulis was 1290 MPa ± 160 MPa[4]
[edit] Gallery
-
Female with egg sac.
-
Immature female.
-
Female with typical red hourglass on abdomen.
-
Male, dorsal view (light coloration).
-
Male, ventral view (light coloration).
-
Male, dorsal view (dark coloration).
-
Male, ventral view (dark coloration).
-
Female, front view, with moth and funnel web spider prey.
-
Female, side view.
-
Female, ventral view.
-
Typical female from California.
[edit] References
- ^ Chamberlin, R. V. & W. Ivie. 1935. The black widow spider and its varieties in the United States. Bull. Univ. Utah 25(8): 1-29. [15, f. 1, 4, 6-14, 21, 23-33]
- ^ Andrade, Maydianne C. B. (5 January 1996). "Sexual Selection for Male Sacrifice in the Australian Redback Spider". Science 271 (5245): 70–2. Bibcode 1996Sci...271...70A. doi:10.1126/science.271.5245.70. http://www.sciencemag.org/cgi/content/abstract/271/5245/70. Retrieved 2007-01-15.
- ^ "Black Widow Spiders". Hastings Reserve. http://www.hastingsreserve.org/Invertebrates/Arachnids/BlackWidows/BlackWidowSpiders.html.
- ^ Blackledge, et al., Todd. "Quasistatic and continuous dynamic characterization of the mechanical properties of silk from the cobweb of the black widow spider Latrodectus hesperus, table 1". The Company of Biologists. http://jeb.biologists.org/cgi/content-nw/full/208/10/1937/TBL1. Retrieved 2009-01-23.
- Minus, A. 2001. "Latrodectus hesperus" (On-line), Animal Diversity Web. Accessed March 8, 2009
- Platnick, N. I. 2008. Theridiidae The World Spider Catalog, version 9.0. American Museum of Natural History.
[edit] External links
Data related to Latrodectus hesperus at Wikispecies
 |
This Theridiidae-related article is a stub. You can help Wikipedia by expanding it. |
