Deinopidae

Common Name

Net-casting spiders, Ogre-faced spiders

Overview

The family Deinopidae, commonly known as net-casting or ogre-faced spiders, exhibits a unique hunting technique among arachnids. These spiders are named for their distinctive method of capturing prey using a small silk web, which they throw over unsuspecting insects.

Taxonomy

  • Order: Araneae
  • Infraorder: Araneomorphae
  • Family: Deinopidae

Key Characteristics

  • Eyes: Most notable for their two large anterior median eyes, which provide exceptional night vision.
  • Body: Typically elongate with long, slender legs.
  • Silk: Unique ability to create a mobile "net" rather than a fixed web.
  • Coloration: Generally brown or gray, aiding in camouflage.

Life Cycle

  • Eggs: Laid in small, silken sacs.
  • Spiderlings: Hatch and go through several molts as they mature.
  • Mature Spiders: Reach sexual maturity, mate, and continue the cycle.

Behavior and Ecology

  • Hunting: Known for their "net-casting" behavior, they use a square-shaped web held between their legs to ensnare prey.
  • Habitat: Found in tropical and subtropical regions, often in forested areas.
  • Nocturnal: Active primarily at night, relying on their excellent vision to hunt.

Notable Species

  • Deinopis spinosa: Known for its relatively large size and widespread distribution in the Americas.
  • Deinopis subrufa: Found in Australia, recognized for its reddish-brown coloration.

Conservation

While not currently considered endangered, habitat destruction could threaten certain species within this family.

Significance to Humans

These spiders are of interest due to their unique hunting strategies and are often studied for their silk properties and night vision capabilities.

Fun Facts

  • Vision: The enlarged median eyes provide better night vision than even owls.
  • Silk Strength: Their silk is capable of stretching significantly, making it highly elastic.
  • Ambush Hunters: Unlike typical web-spinners, they actively use their nets to capture prey.
  • Stealth Mode: At rest, they align their legs along a twig or leaf, becoming nearly invisible.