Hodges#4360

Pronunciation

How to pronounce Echinargus isola: /ˌɛkɪnˈɑːrɡəs ˈaɪsoʊlə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Summary

Echinargus isola, commonly known as Reakirt's blue, is a butterfly belonging to the family Lycaenidae. It is characterized by a wingspan of 16-23 mm and exists in various habitats, primarily feeding on legumes in the larval stage and flower nectar as adults. It migrates and can be found in southern U.S. regions and Central America.

Physical Characteristics

The wingspan ranges from 16–23 mm. The upper side of male is blue with a brownish margin and has one prominent and usually one or two tiny blackish spots near the hind angle of the hind wing. Females are mostly brownish (bluish toward base of wings and body) with more prominent dark spots, usually bordered pale. Below, the dark spots appear grayish or brownish, rimmed white, and with prominent blackish rounded to oval spots on the front wing and some on the hind wing. Prominent dark eye spots are located near the hind angle of the hind wing with metallic scaling.

Identification Tips

Look for the prominent spots on the underside and the coloration of the upper side. In Echinargus isola, males are characterized by their blue color, while females are brownish with some blue. Key distinguishing features from Hemiargus ceraunus include the shape of the postmedian spots and the number of dark spots near the hind angle of the hind wing.

Habitat

Found in fields, gardens, and open areas, as well as habitats with host plants from the Fabaceae family.

Distribution

Central America and the extreme southern U.S. Migrates across the U.S. almost to the Canada–United States border, with rare occurrences in the southern prairies.

Diet

Larvae primarily feed on plants from the Fabaceae family, particularly mesquites (Prosopis species). Adults nectar on flowers such as spearmint and white sweet clover, among others.

Life Cycle

Adults are active from June to October in northern regions and year-round in southern areas. Multiple broods are produced depending on environmental conditions, with one to three broods typically in the north and year-round in the far south.

Reproduction

Adult butterflies typically exhibit multiple breeding cycles as weather permits, with the number of broods varying by location and climate.

Ecosystem Role

Often one of the most abundant butterfly species in the Southwest, contributing to pollination and serving as a food source for predators.

Evolution

Echinargus isola is a monotypic species within the genus Echinargus, with no closely related siblings in this category.

Similar Taxa

• Hemiargus ceraunus

Misconceptions

Due to size and appearance, Echinargus isola may be confused with Hemiargus ceraunus, especially when looked at from the upper side.

Tags

• Butterfly
• Echinargus isola
• Lycaenidae
• Pollinator
• Insect