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Cassius Blue (Leptotes cassius)

Detailing the identifying qualities of the Cassius Blue, including physical features and territorial reach.

 Updated: 2/14/2018; Authored By Staff Writer; Content ¬©

  Cassius Blue  
Picture of Cassius-Blue

When resting on a plant, the small Cassius Blue uses its dark black-and-blue eyespots to confuse predatory birds.

Cassius Blues are members of the Lycaenidae, or the Gossamer-Wing family of butterflies. Gossamer is a light, silky fabric and refers to the fine, delicate wings of this group. The Blues are usually shades of blue or have some blue on their wings. In this species, blue can be seen on the two eyespots under each hindwing as well as on its dorsal area (back side). Cassius Blues bask in the sun with their wings flat, but they rest with them raised, allowing observers to see these bold eyespots clearly. Topside, inner sections of the wings are blue with a thick brown border along the edges. The overall color of under the wings is white with ripples of brown bands across them.

While resting, the butterfly will rub its small hindwings together, mimicking the motion of antennae being cleaned. This may confuse butterfly-eating birds into thinking that the actual head of the butterfly is on the other end of its body. If successfully tricked, the bird attacks the butterfly at the less critical eyespot, giving the butterfly the chance to fly away with only a nip on a hindwing.

The caterpillars of the Cassius Blue are small and green to pale-green. They can be found eating the flowering parts of milkpeas, wild tamarind, and other legumes. Three or more generations can be produced every year, which helps create a stable local population. This species is found in Texas and Florida where they are commonly found all year long. The adults can be seen in gardens, parks, sand dunes, and plant nurseries.

Cassius Blue Information

Category: Butterfly or Moth
Common Name: Cassius Blue
Scientific Name: Leptotes cassius

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Lepidoptera
     Arrow graphic Family: Lycaenidae
      Arrow graphic Genus: Leptotes
       Arrow graphic Species: cassius

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 16 mm to 25 mm (0.624 inches to 0.975 inches)
Identifying Colors: brown, white, black, blue, yellow
Additional Descriptors: eyespots, dots, small, patchy, tail, flying, erratic

North American Territorial Reach (Though Not Limited To): Florida; Texas

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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