Who am I? ³

Hiii! My name is Hemiargus isola, the Reakirt's blue. I am in the same family (Lycaenidae) as the other two tiny blue butterflies in this guide, Western Pygmy-blue (Brephidium exilis) and Marine blue (Leptotes marina). We all look rather similar, so it might be a little hard to tell the difference. If you look closely, we have five black spots un the underside of our forewing with white circles around them; the Western Pygmy-blue is probably smaller than us, and has copper on the forewing underside; and the Marine blue has several brown and white bands for their underside. I'm sure you'll figure it out!

Quick facts ³

Common name: Reakirt's Blue

Scientific name:Echinargus isola (Reakirt 1867)

Family: Lycaenidae - Polyommatinae

Characteristics:

• Wingspan: 3/4 - 1 1/8 inches (2 - 2.9 cm)
• Male upperside: light blue, dark veins, dusky border
• Female upperside is darker than males, mostly brownish
• Underside forewing has five black spots with white encircling each

Host plant: Prefers plants of the family Fabaceae, some of which are yellow sweet clover (Melilotus officinalis), rattleweed (Astragalus), mesquite (Prosopis), indigo bush (Dalea), mimosa (Albizia), and indigo (Indigofera) species

Nectar plant: Seems to prefer herbs - some are spearmint and white sweet clover

Distribution: SW United States, all the way to Southern Central America

Flight times: Most observations seem to be made in the spring (Apr. - Jun.); present all year in South Texas; typically 3 broods from March-November, migrates north after hibernating in the south. See seasonality here: https://www.inaturalist.org/taxa/118914-Echinargus-isola

Where can you find me on campus? ³

Mesquite trees on campus are primarily found around the southern edge of the main Student Union and the west side of Modern Languages. Reakirt blues may also be found on other plants around campus if you get lucky!

References ³

Animal Diversity Web – University of Michigan, https://animaldiversity.org/

Bug Guide – Iowa State University, https://bugguide.net/node/view/15740

Butterflies and Moths of North America - Metalmark Web and Data, https://www.butterfliesandmoths.org/species/Echinargus-isola

Discover Life, https://www.discoverlife.org/

Encyclopedia of Life, https://eol.org/

iNaturalist, https://www.inaturalist.org/home

Sources and Credits

1. (c) Maxine Cruz, some rights reserved (CC BY-NC), uploaded by Maxine Cruz
2. (c) Bryan, some rights reserved (CC BY-NC), uploaded by Bryan
3. (c) Maxine Cruz, some rights reserved (CC BY-SA)

More Info

• iNat taxon page
• Animal Diversity Web
• Biodiversity Heritage Library
• BOLD Systems BIN search
• BugGuide
• Butterflies and Moths of North America
• CalPhotos
• CUIC Insect Images
• Global Biodiversity Information Facility (GBIF)
• HOSTS - a Database of the World's Lepidopteran Hostplants
• Moth Photographers Group
• NatureServe Explorer 2.0
• Pacific Northwest Moths

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