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Red Spotted Ant Mimic Spider (Castianeira  descripta)

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

 Updated: 1/28/2014; Authored By Staff Writer; Content ¬©

  Red Spotted Ant Mimic Spider  
Picture of Red-Spotted-Ant-Mimic-Spider

Seeing a spider close by should set off alarms for many insects, but the Red Spotted Ant Mimic Spider reaps the benefits of good behavior.

The Red Spotted Ant Mimic Spider acts like an ant to gain better positioning when attacking prey. It walks on its back 6 legs while raising the front pair as if they were antennae. This behavior relaxes other ants and insects into thinking the spider's presence is nothing to worry about. It allows the spider to get close to its prey, making it easier to kill and eat.

Adults spin sacs for themselves to rest in. These silken sacs are hidden near anthills or colonies somewhere either in a leaf, in bark cracks or on a node (where a new branch or tree starts growing). They can be found in a variety of habitats including woods, under stones, on shrubs or in parks.

Females use their spider silk to wrap eggs in a sac. They then attach the shiny egg sac to a rock or stone for safe-keeping. Spiderlings overwinter and hatch in the spring, leaving their siblings to find their own way.

Red Spotted Ant Mimic Spider Information

Category: Spider
Common Name: Red Spotted Ant Mimic Spider
Scientific Name: Castianeira  descripta

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: descripta

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; red; white
Additional Descriptors: hairy, biting, venomous

North American Territorial Reach (Though Not Limited To): Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming; Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Nova Scotia; Ontario; Prince Edward Island; Quebec; Saskatchewan; Mexico

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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