Loxosceles gaucho commonly known in English as the gaucho spider.[1] is a highly venomous recluse spider endemic to South America.
| Loxosceles gaucho | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Chelicerata |
| Class: | Arachnida |
| Order: | Araneae |
| Infraorder: | Araneomorphae |
| Family: | Sicariidae |
| Genus: | Loxosceles |
| Species: | L. gaucho
|
| Binomial name | |
| Loxosceles gaucho Heineken & Lowe, 1832
| |
Description and behavior
editAdult females grow up to 7–12 mm, the maximum reported is 14 mm. They are mainly characterized by their brown color, leading to them be colloquially referred to as ''Aranha marrom'' (Portuguese for brown spider) in Brazil, the body is characterized by a pale to dark brown color (often reddish), with a dorsal violin-shaped mark, slightly darker on the carapace, with long and slender legs, without dark marks or stripes. Males have the thoracic region with the clearest impression, consisting of bands, with the anterior portion of the cephalothorax forming in the rear direction a '' V '' design, while pedipalps have the last short articles and curved stylus. Females have the anterior portion of the cephalothorax forming a '' U '' shape backwards. Like many recluse spiders, It is nocturnal, hunting preys such as insects and arthropods with their strong webs, and is more active in the hottest seasons of the year.[1][2]
Range and habitat
editThey usually spin irregular webs in cracks, crevices and corners (which is why some people call them the corner spider), along or under large rocks. It often can be found in human's houses, in dark places, like clothes, shoes, socks and other parts of the house, this species mainly occurs in Central and Southern Brazil, but have been introduced to Tunisia.[1]
Medical significance
editOne study of 81 cases of cutaneous and cutaneous-hemolytic loxoscelism, from a geographical area where most accidents are caused by L. gaucho, reported bite-related symptoms such as massive hemolysis and acute kidney injury (in two cases). In 25 cases, an increase in serum bilirubin and LDH was observed, suggestive of hemolysis. anemia (14.7%), reticulocytosis (56%), thrombocytopenia (17.6%), an increase in D-dimer and fever were also reported.[3] A study with the venom of L. gaucho showed the main local bite reactions, such as pain, edema, erythema, ecchymosis, pallor and dermonecrosis, and systemic like Hemolysis.[4] In the state of São Paulo alone, Brazil, it is responsible for causing viscerocutaneous loxoscelism in 3.1% of cases.[5]
References
edit- ^ a b c "Living Hazards Database (LHD) – Search by Scientific Name" (PDF). Acq.osd.mil. Retrieved 22 March 2022.
- ^ Daniel Manzoni de Almeida. "Estudo Do Potencial Neutralizante..." (PDF). Teses.usp.br. Retrieved 22 March 2022.
- ^ Malaque, Ceila M. S.; Santoro, Marcelo L.; Cardoso, João Luiz C.; Conde, Mayra R.; Novaes, Cristina T. G.; Risk, José Y.; França, Francisco O. S.; Medeiros, Carlos R. de (2011). "Clinical picture and laboratorial evaluation in human loxoscelism". Toxicon. 58 (8): 664–671. doi:10.1016/j.toxicon.2011.09.011. PMID 21986355.
- ^ Magalhães, Geraldo S.; Caporrino, Maria C.; Della-Casa, Maisa S.; Kimura, Louise F.; Prezotto Neto, José P.; Fukuda, Daniel A.; Portes-Junior, José A.; Ferreira, Ana G. C. Neves; Santoro, Marcelo L.; Barbaro, Katia C. (2013). "Cloning, expression and characterization of a phospholipase D from Loxosceles gaucho venom gland". Biochimie. 95 (9): 1773–1783. doi:10.1016/j.biochi.2013.06.002. ISSN 0300-9084. PMID 23770445.
- ^ Barretto, O. C. de O.; Satake, M.; Nonoyama, K.; Cardoso, J. L. C. (March 2003). "The calcium-dependent protease of Loxosceles gaucho venom acts preferentially upon red cell band 3 transmembrane protein". Brazilian Journal of Medical and Biological Research. 36 (3): 309–313. doi:10.1590/S0100-879X2003000300004. ISSN 0100-879X. PMID 12640494.