black widow spider

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1. an arthropod of the class Arachnida.
spider bite in the United States, the two spiders whose bites are most likely to cause a serious reaction are the black widow spider(Latrodectus mactans) and the brown recluse spider(Loxosceles reclusa). Signs and symptoms are associated with the effects of injection of the venom and include pain at the injection site, weakness, muscle pain and cramps, elevated blood pressure, and restlessness. Bites by these spiders must be treated promptly and effectively. First aid is the same as that for a snakebite and includes the following:

1. Wash the wound with soap and water and apply a clean dressing.

2. Apply a constricting band between the area of the bite and the heart.

3. Keep the person calm and transport him to the hospital or medical facility as soon as possible.

4. If swelling becomes apparent, apply a cold compress to the area.
black widow spider Latrodectus mactans, a poisonous spider found in North America; see spider bite.
brown recluse spider Loxosceles reclusa, a poisonous spider found in North America; see spider bite.
vascular spider a telangiectasis due to dilatation and branching of superficial cutaneous arteries, which presents as a bright red central portion with branching radiations, the whole somewhat resembling the configuration of a spider. The lesions may occur singly or in large numbers, and may be nevoid or acquired, being commonly associated with pregnancy and liver disease. Called also nevus araneus, spider nevus, and spider telangiectasia.

black widow spider

Etymology: AS, blac + widewe; ME, spithre
Latrodectus mactans, a species of spider found in the United States, whose bite causes pain and sometimes death.
enlarge picture
Black widow spider with fresh egg case
A venomous spider indigenous to North America—most bites occur in California, most commonly in summer. The black widow spider measures 13 mm in length with a leg spread of 40 mm; it bites with its anterior fangs and may be fatal in very young children and older adults
Management Supportive—topical cleansing, ice, aspirin, opiate analgesics, hot baths, mild sedation, bed rest; for muscle spasms, calcium gluconate, methocarbamol or phenadrine; for hypertensive crises, short-acting antihypertensives; antivenin-Lyovac may be indicated in some patients

black widow spider

Latrodectus mactans Toxicology A venomous spider indigenous to North America–most bites occur in California, more common in summer–which is 13 mm in length with a leg spread of 40 mm and  which bites with anterior fangs and may be fatal in the very young or old Clinical Abrupt sharp, cramping and/or burning pain, dizziness, weakness, spreading to the entire body, activation of autonomic nervous system–N&V, sweating, salivation, tremors, muscle cramping and spasms, twitching, paresthesias, eyelid edema, ptosis; severe cases are accompanied by SOB, tachypnea, respiratory grunting, tachycardia, systolic HTN, acute nephritis and hemoglobinuria in small children Management Supportive, mild sedation, bed rest; for muscle spasms, calcium gluconate, antihypertensives; antivenin-Lyovac may be indicated in some Pts

black wid·ow spi·der

(blak wid'ō spī'dĕr)
A venomous arachnid, attacks always come from female (Latrodectus mactans); reported throughout the United States, but more common in the South; marked on underside with a white 'hourglass' shape. Only small children and immunocompromised patients are likely to die from her bite, although the acute form of the paralysis can cause severe pain.

black widow spider

see latrodectusmactans.
References in periodicals archive ?
Geoff Grewcock, who runs the wildlife sanctuary, said that black widow spiders - which are found on every continent except Antartica - can be "very venomous".
The prevalence of brown widow and black widow spiders (Araneae: Theridiidae) in urban southern California.
We cannot be certain they were definitely black widow spiders but we believe they were and we treat every situation like this with utmost care because we wouldn't want to take any chances.
indistinctus and other black widow spider species are occasionally found in suburban gardens and bites have occurred inside homes, they are predominantly veld species.
A pair of black widow spiders found in a classic car have found a new home at Bristol Zoo.
The attraction will feature everything from black widow spiders and venomous lionfish to stinging jellyfish and vipers in a series of innovative new displays - including Tarantula Tower where visitors will be able to step inside a Perspex tower surrounded by more than 50 giant spiders.
I started to catch rattlesnakes, black widow spiders and scorpions and tried to make them my friends.
But then I read that Black Widow Spiders will soon be living in Britain.
DEADLY black widow spiders and scorpions could be able to survive and breed here in the future thanks to our rising temperatures, it has been claimed.
Until World War II, the threads of black widow spiders were used as crosshairs in optical devices, including microscopes and telescopes.
Female black widow spiders can kill a small child or elderly person and are ranked in the top five of most venomous arachnids.
The Cage, created by Jerome Robbins in 1951 to music by Stravinsky, uses stylized choreography to investigate an insect society, somewhat like that of preying mantises or black widow spiders, in which the female finds the male's existence superfluous after mating and kills him without compunction.