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Mexican Orange-Kneed Tarantula (Euathlus smithii)

Detailing the identifying qualities of the Mexican Orange-Kneed Tarantula, including physical features and territorial reach.

 Updated: 1/24/2014; Authored By Staff Writer; Content ¬©

  Mexican Orange-Kneed Tarantula  
Picture of Mexican-Orange-kneed-Tarantula

The endangered Mexican Orange-Kneed Tarantula is protected by international laws so it can remain a part of its natural ecosystem for generations to come.

Tarantulas are magnificently large and extremely hairy. Including legs, some can grow as long as 150 mm. This particular species has bright orange patches on its "knee" joints and lower legs joints as well and it is this unique coloration has led to their decline.

Orange-Kneed Tarantulas became popular 'pets' and were taken from the wild and sold in stores. Their trade has now become illegal and they are protected as an endangered species by being placed on the CITES list.

Males are generally smaller and thinner than females, though their legs are longer. They are territorial and aggressive with other intruding males. Females are larger and live longer by an average of 10-20 years longer. Males generally live about 10 years, when they become sexually mature, and then die.

North American tarantula venom is not lethal, but bites can be as painful as a bee sting. Also, the bristles on their abdomen break off easily and can penetrate skin, causing irritation and redness to prey (mice) or people trying to handle them. This is a 'look, but don't touch' species.

Nocturnal in nature, they are most active at night and are hunters, not spinners. They may use their silk to line their daytime hideouts, but not to catch prey.

Mexican Orange-Kneed Tarantula Information

Category: Spider
Common Name: Mexican Orange-Kneed Tarantula
Scientific Name: Euathlus smithii

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Arachnida
    Arrow graphic Order: Araneae
     Arrow graphic Family: Theraphosida
      Arrow graphic Genus: Euathlus
       Arrow graphic Species: smithii

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 35 mm to 60 mm (1.365 inches to 2.34 inches)
Identifying Colors: black, orange, gray, white
Additional Descriptors: hairy, orange, knees, biting, venomous

North American Territorial Reach (Though Not Limited To): Arizona; Nevada; New Mexico; Texas; 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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