Black Widow Spider Page

I recently acquired a Black Widow Spider (Latrodectus). The gender is undetermined yet, but I suspect it is a female due to its large size. I acquired it on August 24/2006. I have decided to keep the Spider but have yet to setup a permanent home for it. This is a bit of an oddity, since I am not really a fan of Arachnids and I am mainly into reptiles.

It has been very interesting watching the spider at work both weaving intricate webs, to attacking crickets that I feed it and lugging its prey to the top of the container to feed on. I've never really liked spiders but did find them interesting and since I got this one it peaked my interest enough to keep it.

I have sold this Black Widow off earlier in the year. I no longer have any Black Widows.

Black Widow Spider Pictures

Black Widow Spider Information

Description:

The Black Widow spider is a spider notorious for its neurotoxic venom and identified by its distinctive red hourglass markings on the bottom of its abdomen and black body.

Females are usually shiny black with most commonly red markings, can range in color from white to yellow and various shades of orange and red. A large female can grow to 1.5" (38mm) counting leg span and the body is about 0.5" (13mm). Male Black Widow spiders are about half the size of females or smaller.

As with most poisonous creatures, the brightly colored markings serve as a warning to predators. Eating a Black Widow will normally not kill a small predator (birds ect) but the sickness that follows digestion is enough to remember that bright means not to eat. Because the adult female Black Widow typically hangs and moves about its web upside down, its hourglass markings are on its front. Young females however spend a large amount of time in search of optimal environments, and have brightly colored marks on their backs as well so that predators can see the markings when that are on their legs. These markings fade and disappear once adult. Males have similar markings but are not as large and not as bright.

As a characteristic of all arthropods, Black Widow spiders have a hard exoskeleton composed of Chitin and Protein.

Prey:

Black Widow spiders typically prey on a variety of insects, but occasionally they do feed upon woodlice, diplopods, chilopods and other arachnids. When prey is entangled by the web, they quickly come out of their retreat, wraps the prey securely in its strong web, then punctures and poisons its prey. The venom takes about ten minutes to take effect, meanwhile the prey is held tightly by the spider. When movement of the prey ceases, digestive enzymes are released into the wound. The Black Widow then carries its prey to its retreat before feeding.

Reproduction:

Mature males will spin a sperm web, depositing semen on it and also charges his palpi. Black Widow spiders reproduce when the male inserts his palpus into the females spermathecal openings. The female deposits her eggs in a globular silken container in which they remain camouflaged and guarded. A single female can produce up to 9 egg sacs per summer, each containing about 400 eggs. Usually eggs incubate for 20-30 days. Many of the eggs/spiderlings are lost to cannibalism, lack of food, or lack of proper shelter. It takes 2-4 months for Black Widow Spiders to mature enough to breed, and 6-9 months for full maturation. Females can live for up to 5 years, males are much shorter. Lifespan depends upon environment, shelter being the greatest determining factor,

food the second greatest factor.

Natural Enemies:

Parasites to the egg sack include: the flightless Scelionid Wasp (Baeus latrodecti), and members of the Chloropid Fly genus (Pseudogaurax).

Predators of the adult spiders include a few wasps, most notably the Blue Mud Dauber (Chalybion californicum), and the Spider Wasp (Tastiotenia festiva).

Other species will occasionally and opportunistically take Black Widows as prey, but the preceding all exhibit some significant preference.

The Venom; Components and Effects:

(To be added)

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