VIÚVA-MARROM, A PARENTE DA VIÚVA-NEGRA! - SOBRE ANIMAIS

ATENÇÃO! NÃO MANIPULE ANIMAIS SILVESTRES, UM ERRO DE MANEJO OU IDENTIFICAÇÃO PODE OCASIONAR UM ACIDENTE GRAVE, E NÃO CONSEGUIMOS PREVER AS REAÇÕES DE UM ANIMAL!
Redes Sociais:
Facebook:
/ sobreanimais14
Instagram:
@sobre_animaisyt
Twitter:
@SobreAnimais2
TikTok:
vm.tiktok.com/...
Link do artigo citado no vídeo: drive.google.c...
Informações Extras:
Latrodectus, conhecido pelo nome comum de aranhas-pretas ou viúvas-negras, é um género de aranhas pertencente à família Theridiidae, que inclui 32 espécies confirmadas. O nome comum viúva negra deriva da maioria das espécies deste género praticar o canibalismo sexual, sendo que a fêmea devora o macho após a cópula.
Cerca de 75% das picadas em adultos injetam pouco veneno e causam apenas dor e desconforto local.
Quando há envenenamento significativo de lactrotoxina 15 a 30 minutos depois da picada aparece dor irradiante, calafrios e muito suor no local. Uma hora depois começam tremores, contraturas, rigidez e câimbras dolorosas, como um tetanismo. Pode haver também febre, salivação, sede, náuseas, vômitos, hipertensão e excitação psicomotora. Possíveis complicações incluem taquicardia, hipertensão, arritmia cardíaca, choque cardiogênico, anúria e priapismo.
O tratamento é feito com neostigmina, um parassimpaticomimético, para bloquear os efeitos adrenérgicos do veneno e gluconato de cálcio para reduzir a dor e os espasmos musculares. Um analgésico, relaxante muscular e/ou ansiolítico também podem ser usados para aliviar os outros sintomas. Os sintomas podem demorar de 2 a 6 dias para melhorar completamente.
Wikipedia
The brown widow spider (Latrodectus geometricus Koch) belongs to the family Theridiidae (Foelix 2011, Howell and Jenkins 2004). Theridiids are known as comb-footed spiders because of the comb-like rows of stout, curved bristles on the tarsi (feet) of the hind pair of legs (Figure 1). They are also known as cobweb spiders because of their irregular webs.
The genus Latrodectus is composed of two phylogenetic groups - the mactans (black widow) clade and the geometricus (brown widow) clade (Garb et al. 2004).
Brown widows are also sometimes called gray widows (Liu et al. 2009) or brown button spiders (Heeres et al. 1991, Nel et al. 2014). The genus name Latrodectus is from Greek root words meaning “biting in secret” (Cameron 2005, Maretić and Lebez 1979). On a web site on the brown widow (Spiders.us 2016a) it is stated that the name Latrodectus “refers to the painlessness of the initial bite and the fact that it often goes unnoticed until symptoms present”. In one study, 58.2% of 177 patients did not perceive pain immediately at the time of the bite (Maretić 1987). However, the initial effect of the bites of black widows varies from unnoticeable to extremely painful (Balentine 2015, Barron 1960, Blahd and O’Connor 2014). Therefore, it seems equally likely that the name refers to the secretive nature of the spiders and that the victims often do not see what has bitten them.
The brown widow is believed to be native to southern Africa but was originally described from South America (Vetter 2013). Its distribution is now pantropical and also includes many subtropical areas around the world (Figure 2) (Brown et al. 2008, Muslimin et al. 2015, Suchard 2009). In the U.S., it was originally introduced into southeastern Florida (Pearson 1936, McCrone and Stone 1965). It has now spread northward throughout Florida, into Georgia, North and South Carolina and westward to Alabama, Mississippi, Louisiana, Texas, and also has been introduced into California and Hawaii (Bianchi 1945, Brown et al. 2008, Garb et al. 2004, Suchard 2009). Richman (2013) stated, "The Brown Widow, Latrodectus geometricus Koch, has recently been reported in Arizona and is expected to invade New Mexico eventually, if it has not already". Therefore, New Mexico was included in the distribution map below (Figure 2). The brown widow will likely continue to extend its range both in the U.S. and abroad into areas where environmental conditions are suitable.
Barcoding (DNA sequencing of the gene for mitochondrial cytochrome oxidase subunit I) of brown widow specimens from around the world shows minimal genetic divergence. This supports the hypothesis that the expansion of the brown widow’s distribution around the world is relatively recent and is likely the result of human activities (Garb et al. 2004). There is some evidence of competitive displacement of black widows following introduction of brown widows into an area (Bianchi 1945, Vetter et al. 2012a).
Adults: Males (body length 2-4 mm) are much smaller than females (body length 7-10 mm) (Benjamin and Zschokke 2003, Edwards and Marshall 2002). Females are highly variable in pattern and color - they can be almost white, gray, light brown, dark brown or almost black (Edwards 2002, Heeres 1991, Müller 1993b).
Featured Creatures UF|IFAS