Therophosidae

Family Theraphosidae

Common Name

Tarantulas

Overview

The family Theraphosidae, commonly known as tarantulas, comprises large and often hairy spiders. These arthropods are among the most popular and recognizable spiders due to their size and striking appearance. They are found in various habitats around the world and are well-known for their role in popular culture and the pet trade.

Taxonomy

Key Characteristics

  • Size : Tarantulas can range from small (around 2.5 cm) to very large (up to 30 cm in leg span).
  • Coloration : They exhibit a wide variety of colors and patterns, often with iridescent or metallic sheens.
  • Body Structure : They have two main body segments: the cephalothorax and abdomen. Their bodies are covered in hair-like setae.
  • Fangs : Equipped with long, powerful fangs capable of delivering venom.

Life Cycle

  • Eggs : Laid in a silk sac, with hundreds of eggs per sac.
  • Spiderlings : Young spiders that emerge from the egg sac and undergo several molts before reaching adulthood.
  • Adults : Depending on the species, tarantulas can live from 5 to 25 years. Females generally outlive males significantly.

Behavior and Ecology

  • Habitat : Found in diverse environments including rainforests, deserts, and grasslands. They are primarily terrestrial, but some species are arboreal.
  • Diet : Carnivorous, feeding mostly on insects, though larger species can prey on small vertebrates.
  • Defense Mechanisms : Some species possess urticating hairs which they can flick to deter predators. Venom is generally mild to humans but effective against small prey.

Notable Species

  • Grammostola rosea (Chilean Rose Tarantula)
  • Brachypelma smithi (Mexican Redknee Tarantula)
  • Poecilotheria regalis (Indian Ornamental Tarantula)
  • Theraphosa blondi (Goliath Birdeater)

Conservation

While many tarantula species are not currently endangered, habitat loss and the pet trade pose risks. Some species have protection under international law (CITES) to prevent over-collection and ensure sustainable populations.

Significance to Humans

  • Pet Trade : Tarantulas are popular exotic pets due to their fascinating behavior and manageable care requirements.
  • Medical Research : Their venom is studied for potential medical applications.
  • Ecological Importance : As predators, they help control populations of insects and other small animals.

Fun Facts

  • Tarantulas are one of the few spiders with urticating hairs, which they can use as a defense mechanism.
  • The Goliath Birdeater is the largest spider in terms of mass and size.
  • Despite their fearsome reputation, tarantula bites are rarely dangerous to humans.
  • Some tarantulas can live up to 25 years, making them long-term pets.
  • Tarantulas have the ability to regenerate lost limbs during molting.