Diet

• Caterpillars: Feed primarily on legumes (Fabaceae), especially Senna and related cassia-type plants. Desmodium incanum is another documented host.

• Adults: Feed on nectar from a variety of small flowering plants.

Range

• Boisduval's Yellow occurs from Costa Rica north through Central America and Mexico, including both the Pacific and Gulf regions of Mexico.

• Guerrero is within its range, and it occurs in suitable warm habitats in western Mexico. It can also occur around the Zihua area, particularly where its leguminous host plants grow.

• It is sometimes encountered well north of its normal range, including southern Texas, Arizona, and New Mexico.

Habitat

• Found in subtropical forest, forest edges, tropical scrub, roadsides, pastures, and other sunny or partially disturbed habitats.

• It generally favors warm areas supporting abundant flowering plants and its Senna and related host plants.

Description

• A medium-sized yellow with a wingspan of approximately 38–51 mm.

• The upper surface is lemon yellow, with black markings along the wing margins.

• The hindwings are slightly pointed, a useful feature when distinguishing it from several other yellow butterflies in the same region.

• Males have a relatively broad black hindwing border that projects into the yellow ground color. The forewing also has a relatively weak dark "dog's-head" pattern.

• Females generally have a more conspicuous black forewing apex but a narrower black hindwing margin.

• The underside is more subdued yellow to yellow-brown, with darker markings that provide useful identification clues when the butterfly is perched with its wings closed.