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Black Tail Crab Spider (Synema parvulum)

Detailing the identifying qualities of the Black Tail Crab Spider, including physical features and territorial reach.

 Updated: 2/8/2018; Authored By Staff Writer; Content ¬©

  Black Tail Crab Spider  
Picture of Black-Tail-Crab-Spider
Picture of Black-Tail-Crab-Spider Picture of Black-Tail-Crab-SpiderPicture of Black-Tail-Crab-SpiderPicture of Black-Tail-Crab-Spider

Though the Black Tail Crab Spider lacks giant claws, it makes up for it with mighty jaws and a great work ethic.

Crab spiders have longer front legs that sit more forward on the body than typical spiders. Their back pairs of legs are so much shorter and further back than the front pairs that it gives them the appearance of a crab. This particular species is very tiny and reddish-brown. The abdomen is wide and round but also flat on top. The bottom has a black crescent-shaped black mark at the end of the abdomen, as if its rear end was dipped in black ink.

Crab spiders do not use a web to catch prey. They ambush insects, lying in wait inside or on flowers. Because this spider preys on insects that may damage plants and flowers (like aphids and certain beetles), it is considered helpful to the garden ecosystem. They have also been found on piled wood and tree bark. The Black Tail Crab Spider will grab its insect prey, using its long and strong front legs to help pin the victim down. It then bites the prey with its strong jaws, immobilizing it with venom for later consumption. The Black Tail Crab Spider is not known to bite humans,however, and it takes little interest in our activity. Their venom is not poisonous.

Picture of the Black Tail Crab Spider
Picture of the Black Tail Crab Spider

Black Tail Crab Spider Information

Category: Spider
Common Name: Black Tail Crab Spider
Scientific Name: Synema parvulum

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Arachnida
    Arrow graphic Order: Araneae
     Arrow graphic Family: Thomisidae
      Arrow graphic Genus: Synema
       Arrow graphic Species: parvulum

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 5 mm to 7 mm (0.195 inches to 0.273 inches)
Identifying Colors: brown; black; red
Additional Descriptors: crab, butt, dipped, crescent, legs, venomous, biting, helpful

North American Territorial Reach (Though Not Limited To): Alabama, Arizona, Arkansas, Florida, Georgia, Illinois, Indiana, Kentucky, Louisiana, Mississippi, Missouri, Nevada, New Jersey, New Mexico, North Carolina, Ohio, Oklahoma, South Carolina, Tennessee, Texas, Utah, Virginia, West Virginia

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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