Black Widow Spider

Children's Zoo

Location

In the Zoo
Size
Male
Female
Height:
Length:
1/8 inch
3/8 inch
Weight
1-2 pounds
Maturity:
70-90 days
70-90 days

Geographic Range

In the U.S. they're found from Massachusetts to Florida, west to California, Texas, Oklahoma and Kansas; Also found in Canada, Mexico, The West Indies, and South America

Scientific Information

Scientific Name:
Latrodectus mactans
Class:
Arachnida
Order:
Aranae
Family:
Theridiidae
Genus:
Latrodectus

Lifestyle and Lifespan

Diet:
Carnivorous
Activity Time Frame:
Nocturnal
Interactivity:
Solitary
Sexual Dimorphism:
Yes
Gestation:
20 days
Lifespan in the Wild:
1-3 years
Lifespan in Captivity:
4 years

Conservation

Status:
Threats:

Characteristics

Black Widow spiders are known for their potent venom, which is 15 times as potent as rattlesnake venom.

Species Specifics

The Three-Toed Box Turtle has a tan or olive carapace with darker seams and some vague markings. They also have orange, red and yellow spots on their head and forelimbs.The defining characteristic of this turtle is its toes. It has three toes on its back feet, thus why its known as the Three Toed Box Turtle. Hybrid Three Toed Box Turtles who have been interbred with Common Box Turtles sometimes have four toes instead of three. Sexual Dimorphism: males are larger. Males are slightly larger on average, the posterior lobe of their plastron is concave, and the claws on their hind legs are short, thick and curved. Males also have thicker and longer tails. Females' rear claws are longer, straighter and more slender, and the posterior lobe of their plastron is flat or slightly convex. There are four subspecies of Terrapene carolina in the United States. Terrapene carolina bauri (Florida Box Turtle) lives on the peninsula of Florida. Terrapene c. major (Gulf Coast Box Turtle) ranges from the panhandle of Florida westward along the Gulf cost to eastern Texas. Terrapene c. triunguis (Three-toed Box Turtle) lives in the Mississippi River Valley from northern Missouri southward across southeastern Kansas and eastern Oklahoma into southcentral Texas; and southeastward across western Tennessee and Georgia to the coastal lowlands.

Physical Characteristics

As part of the family of comb-footed spiders, they have 6-10 comb-like bristles on the hind tarsi. They use their combs to fling silk strands over any captive that gets caught in the web. The swathed victim is hauled to a rest site on the web, injected with venom and later eaten.

Ecology

Habitat

Most common in the South of America. Found among fallen branches, under stones, in outbuildings and under objects such as furniture.

Distribution

Habitats: Found mostly in the Eastern United States, Box Turtles occur as far north as Michigan and Maine, South to Florida, and as far West as Texas and Kansas. Found rarely above 1,000 feet in elevation, preferring low land habitats where water collects. Commonly associated with deciduous forests having high leaf litter and moisture these turtles are often located near rivers, streams, ponds, lakes and other bodies of fresh water, however, they are not good swimmers.

Diet

Black Widows primarily eat insects. However they will also eat diplopods, wood lice, chilopods, and other arachnids.

Ecological Web

Black Widow Spiders help to control insect populations.

Activity and Behavior

Activity Pattern

During the day, the female spider hangs upside down in her web, displaying her red hourglass marking as a warning to potential predators. If prey gets caught in her web, she will wrap it in silk, bite it, and drag it to a retreat inside of her nest to consume it. When eating, she will use her cheliceral teeth to mash up her prey. Then she pours digestive enzymes onto it, and sucks up the resulting food. This whole digestion process takes place outside of the spider's body.

Behavior

When disturbed, black widow spiders will fall out of their web and play dead to avoid predation.

Social Behavior

Black Widow Spiders only exhibit social behavior when searching for mates.

Reproductive Behavior

During the mating season, a mature male spins a small 'sperm web', or web in which he deposits a small amount of semen. He then covers his pedipalps in sperm, abandons his home, and travels in search for females. Once he finds a female, courtship begins. The male begins by vibrating the threads of the female's web, alerting her to his presence. If she is receptive, mating will take place when the male inserts his papal organs into the spermathecal openings of the female. His sperm is released onto her eggs, which are then laid onto a small web and covered with more silk until they are completely surrounded by a cocoon. This cocoon is then guarded or carried by the female until the eggs hatch and spiderlings emerge. A female black widow spider can store the sperm from one mate and use it throughout her lifetime.

Offspring

One egg sac can contain anywhere from 20-900 eggs. While the female spider cares for the egg sac during gestation, parents provide no parental care once the eggs have hatched.

Conservation

Status

Three-Toed Box Turtles are not considered endangered at the national level in the United States, Canada or Mexico, although several U.S. states, including Michigan, New Hampshire, Massachusetts and Connecticut, list T. carolina as a species of special concern. It is considered endangered in Maine. IUCN: VulnerableCITES: Appendix II

Historical

Due to a widespread, consistent and persistent decline of the species, the ICUN considers the Box Turtle to be a Vulnerable Species. The decline is associated with anthropogenic causes, or manmade causes centering on urbanization. Agricultural use of pesticides within a shared water shed has negatively impacted young turtle survivability due to malformed eggs. Introduction of synanthopic predator species, (species who live near and benefit mutually from human settlement and urban habitats) such as ravens, coyotes and raccoons, are increasing in numbers as humans continue to urbanize.

Current Threats

Introduced Non-Native, Domestic, and Invasive Species

Our Role

No items found.

How You Can Help

Please be aware of the pets you choose to buy. Never get a pet that has been taken from the wild and never return a pet to the wild. Be aware of pesticide applications so as to not poison native animals that benefit your ecosystem. Finally, be conscious of your trash and waste so as to not attract unwanted animals such as ravens.

Fascinating Facts

The common name, Black Widow Spider, originates from the females' behavior to sometimes eat the male spider after mating.

Their only known predator is the mud-dauber wasp.

Of all the Gerrhosaururidae lizards (Plated lizards) they are the most armored.

References

McCorkle, Matthew. "Latrodectus mactans." Animal Diversity Web. N.p., n.d. Web. 17 Apr. 2017.

Kaston, B.J. 1978. How to Know the Spiders. Wm C. Brown Co, Dubuque, Iowa.

Milne, Lorus and Margery.1980. The Audubon Society Field Guide to North American Insects and Spiders. Alfred A. Knopf, New York.

Preston-Mafham, Rod. 1991. The Book of Spiders. Chartwell Books, Edison, NJ.