Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

Cassius Blue
Leptotes cassius (Cramer, 1775)


Family: Lycaenidae
Subfamily: Polyommatinae
Identification: Upperside of males pale blue; females with white patches. Underside tan with broken pale lines; forewing inner margin has "blank" areas with no spots.
Wing Span: 3/4 - 1 3/8 inches (2 - 3.5 cm).
Life History: Eggs are laid singly on flower buds of the host plant; caterpillars eat flowers and seedpods. Predation and parasitism may be discouraged by ants, which tend the caterpillars and feed on their sugary secretions.
Flight: All through the year in southern Florida and South Texas. Number of broods has not been determined.
Caterpillar Hosts: Ornamental leadwort (Plumbago capensis), rattlebox (Crotalaria incana), hairy milk pea (Galactia volubilis), and lima bean (Phaseolus limensis). Larva has been reared on the crenulate lead plant, Amorpha crenulata.
Adult Food: Nectar from shepherd's needle, lippia, and many other flowers.
Habitat: Subtropical thorn scrub, forest edges, weedy fields, residential areas.
Range: Florida and the Keys; Texas south through the West Indies, Mexico, and Central America to South America. Strays to New Mexico, Kansas, Missouri, and South Carolina.
Conservation: Not usually required.
NCGR: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
Management Needs: None reported.
Comments: Suzanne Koptur (kopturs@fiu.edu) e-mailed to say that her graduate student Lauren Linares reared a caterpillar on the crenulate lead plant. The adult was determined by Dr. William Kern Jr. of the University of Florida's Institute of Food and Agricultural Sciences in Fort Lauderdale, Florida.

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