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Ant Mimic Spider (Castianeira longipalpis)

Detailing the identifying qualities of the Ant Mimic Spider, including physical features and territorial reach.

 Updated: 1/31/2018; Authored By Staff Writer; Content ¬©

  Ant Mimic Spider  
Picture of Ant-Mimic-Spider
Picture of Ant-Mimic-Spider Picture of Ant-Mimic-SpiderPicture of Ant-Mimic-SpiderPicture of Ant-Mimic-SpiderPicture of Ant-Mimic-Spider

If the appearance the Ant Mimic Spider isn't enough to fool prey, then its clever behavior certainly helps accelerate mealtime.

Small and fast, Ant Mimic Spiders have similar coloring to certain types of ant. With bodies shaped a lot like ants, it may be difficult at first glance to tell that this creature is actually a spider. In an effort to blend in with their food source, Ant Mimic Spiders walk with their front pair of legs raised in the air, sometimes rubbing them together, mimicking antennae. They may also occasionally tap their abdomen to the ground. These cunning behaviors can make it tricky even for a human to identify it as a spider. As with most arachnids, all is revealed by simply counting legs.

The resemblance to ants isn't just an aid in hunting; it can also act as a defense against predators. Many types of ants taste pungent to birds, small mammals, and other insects thanks to natural formic acid secretions, so looking and acting like an ant can deter typical spider predators from eating Ant Mimic Spiders. Add in the likelihood that an Ant Mimic Spider often lives near ant hills or nests, and it is possible to almost create a safe zone for itself.

Females are only slightly larger than males. They eat smaller insects and lay a small clutch of eggs on circular, flat, white egg sacs. Eggs hatch in autumn and spiderlings overwinter until spring. Ant Mimic Spiders can be found anywhere ants are found: fields, lawns, gardens, woods, on trees and under stones. Look for a tubular 'retreat,' a sac of silk inside a rolled-up leaf or under plant matter. When not hunting, they rest inside these sacs.

Picture of the Ant Mimic Spider
Picture of the Ant Mimic Spider

Ant Mimic Spider Information

Category: Spider
Common Name: Ant Mimic Spider
Scientific Name: Castianeira longipalpis

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Arachnida
    Arrow graphic Order: Araneae
     Arrow graphic Family: Corinnidae
      Arrow graphic Genus: Castianeira
       Arrow graphic Species: longipalpis

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 5 mm to 10 mm (0.195 inches to 0.39 inches)
Identifying Colors: black; yellow; orange; red
Additional Descriptors: ant-like, patterned, venomous, banded, striped, antennae, legs

North American Territorial Reach (Though Not Limited To): Alabama; Florida; Georgia; Louisiana; Mississippi; North Carolina; South Carolina

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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