Theraphosidae

Common Name

Tarantulas

Overview

Theraphosidae is a family of large, often hairy spiders commonly referred to as tarantulas. They are renowned for their impressive size, diverse coloration, and sometimes intimidating appearance. These arachnids can be found in a variety of habitats, ranging from rainforests to deserts, and have become popular in the exotic pet trade.

Taxonomy

Key Characteristics

  • Size: Ranges from 2.5 cm to 30 cm in leg span.
  • Coloration: Varies greatly; can be brown, black, or vibrantly colored.
  • Body Structure: Robust bodies; hairy, with a distinct set of eight eyes.
  • Fangs: Prominent, capable of delivering venom.
  • Setae: Specialized urticating hairs used for defense in some species.

Life Cycle

  • Egg: Laid in large egg sacs containing 50-2000 eggs.
  • Spiderlings: Hatch from eggs; often stay close to the mother initially.
  • Juvenile: Undergo multiple molts as they grow.
  • Adult: Females live up to 20 years or more; males live around 5-7 years.

Behavior and Ecology

  • Habitat: Prefer humid, warm environments but are adaptable.
  • Diet: Carnivorous, feeding on insects, small mammals, and other invertebrates.
  • Burrowing: Many species are fossorial, creating burrows for protection.
  • Defense Mechanisms: Use urticating hairs, venomous bites, and intimidation displays.

Notable Species

  • Brachypelma smithi: Known as the Mexican Redknee, a popular pet species.
  • Pterinochilus murinus: Also known as the Orange Baboon Tarantula; highly defensive.
  • Theraphosa blondi: The Goliath Birdeater, regarded as the largest tarantula by mass.

Conservation

Several species are threatened by habitat destruction and poaching for the pet trade. Conservation efforts focus on habitat preservation and regulating the trade of tarantulas.

Significance to Humans

Tarantulas are popular in the exotic pet industry due to their fascinating appearance and behaviors. They also play important roles in their ecosystems as both predators and prey. In some cultures, tarantulas are seen as symbols of fear while in others they are respected.

Fun Facts

  • Speed: Tarantulas can move quickly in short bursts to capture prey or escape threats.
  • Molting: Tarantulas must molt, shedding their exoskeleton, to grow. This can be a vulnerable time for them.
  • Regeneration: They can regenerate lost limbs, typically during molts.
  • Diet: Captive tarantulas are often fed crickets, mealworms, and occasionally small vertebrates.
  • Venom: While tarantula venom is not usually harmful to humans, it can cause localized pain and irritation.