Trachelidae

Common Name

Trachelas Spiders

Overview

Trachelidae, commonly referred to as Trachelas spiders, is a family of araneomorph spiders. These spiders are typically small and often unnoticed, but they inhabit various ecosystems across the globe, particularly favoring leaf litter and low vegetation.

Taxonomy

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Arachnida
  • Order: Araneae
  • Infraorder: Araneomorphae
  • Family: Trachelidae

Key Characteristics

  • Size: Generally small, ranging from 3 to 7 millimeters in body length.
  • Coloration: Often reddish-brown to black with pale-colored legs.
  • Body Shape: Broadly oval body and a flattened cephalothorax.
  • Eyes: Eight eyes arranged in two rows.
  • Chelicerae: Equipped with prominent, protruding chelicerae (mouthparts).
  • Silk Usage: Use silk to construct retreat webs rather than capturing prey.

Life Cycle

  • Eggs: Females lay eggs in silk sacs hidden in leaf litter or other secluded areas.
  • Spiderlings: Hatch from eggs and undergo multiple molts before reaching maturity.
  • Mature Spiders: Adulthood may be reached in several months, and life span can range from one to two years depending on species and environmental conditions.

Behavior and Ecology

  • Habitat: Prefer wooded areas, leaf litter, and low vegetation.
  • Diet: Primarily insectivorous, preying on small arthropods.
  • Nocturnal Activity: Most species are nocturnal hunters.
  • Predation: Utilize ambush strategies to capture prey.

Notable Species

  • Trachelas tranquillus: A species common in North America, known for its reddish coloration and preference for leaf litter habitats.
  • Trachelas minor: A smaller species, also prevalent in North America, distinguished by its stealthy hunting behavior.

Conservation

Generally, Trachelidae spiders are not known to be under significant threat. They thrive in a range of habitats and seem to adapt well to environmental changes on a local scale.

Significance to Humans

  • Pest Control: Help control populations of small arthropods and insects.
  • Medical Impact: Bites are uncommon and not dangerous to humans.

Fun Facts

  • Trachelidae spiders are sometimes nicknamed "running crab spiders" due to their speed.
  • They do not build webs to capture prey; instead, they are active hunters.
  • During the day, they remain hidden in a silk retreat.
  • Some species have been observed utilizing mimicry to blend into their surroundings.
  • Despite their small size, Trachelidae spiders are effective predators in their micro-habitats.