Diet

• Caterpillars feed on a variety of legumes (Fabaceae) and leadworts (Plumbaginaceae).

• Eggs are laid singly on flower buds, and the caterpillars feed primarily on flowers, developing seedpods and young growth.

• Ants sometimes tend the caterpillars and feed on their sugary secretions, providing the larvae with a degree of protection.

Range

• Leptotes cassius has an extensive tropical and subtropical distribution from the southern United States through Mexico and Central America, the Caribbean and much of South America.

• In Mexico it is widespread, including Guerrero, and it occurs in the Zihua area where suitable warm, open habitats are present.

Habitat

• The Cassius Blue favours sunny, open and semi-open habitats, including tropical scrub, forest edges, clearings, old fields, roadsides, gardens and disturbed vegetation.

• It is particularly associated with areas supporting its low-growing leguminous host plants.

• Adults are often found flying close to the ground and can be surprisingly inconspicuous despite their pale blue upperwings.

Description

• This is a very small blue butterfly with a wingspan of approximately 20–35 mm.

• Males have pale to bright blue upperwings with narrow dark margins. Females are generally paler, with broader dark borders and variable blue colouring toward the wing bases.

• The underside is tan to greyish, crossed by numerous narrow, broken pale and dark lines, giving the genus its characteristic "zebra blue" appearance.

• Each hindwing has two distinctive eyespots near the outer margin. The larger eyespot contains metallic blue scales and is surrounded by orange or reddish colouring.

• The combination of tiny size, striped underside and paired hindwing eyespots is particularly useful for distinguishing it from other small blues in western Mexico.