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Forbes' Silk Moth (Rothschilida forbesi)

Detailing the identifying qualities of the Forbes' Silk Moth, including physical features and territorial reach.

 Updated: 8/7/2017; Authored By Staff Writer; Content ¬©

  Forbes' Silk Moth  
Picture of Forbes-Silk-Moth

The nocturnal Forbes' Silk Moth is a sight to behold thanks to its late-night activity, large wingspan, handsome pattern, and small range.

Forbes' Silk Moth is a part of the Saturniidae family hosting some of the largest moths in North America. This species has a limited range, despite its grand size and has only been seen in southern Texas and Mexico. Its rounded wings have four large transparent spots on them, two on each side. For this reason, its Spanish name is Cuatro Espejos meaning "four mirrors". The dark brown interior of the wings is bordered with a light brown and edged with a creamy white rim. They rest with wings flat.

Caterpillars are white, black, and yellow. White fleshy bodies have thick black bands studded with yellow bumps topped with spiky hairs. After feeding on leaves of ash and willow trees, they pupate and become winged adults. Two generations a year are produced with adults on wing in early spring and again in mid-autumn.

Forbes' Silk Moth Information

Category: Butterfly or Moth
Common Name: Forbes' Silk Moth
Scientific Name: Rothschilida forbesi
Other Name(s): Cuatro Espejos

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Lepidoptera
     Arrow graphic Family: Saturniidae
      Arrow graphic Genus: Rothschilida
       Arrow graphic Species: forbesi

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 110 mm to 125 mm (4.29 inches to 4.875 inches)
Identifying Colors: brown, white, red, orange, black
Additional Descriptors: four, spots, marks, night, nocturnal, rounded, flying, large, big

North American Territorial Reach (Though Not Limited To): 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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