North American Butterflies and Moths List

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Butterflies of North America

Nickerbean Blue (Hemiargus ammon)
JPG -- species photo

Nickerbean Blue (Hemiargus ammon [Lucas])

Wing span: 7/8 - 1 1/8 inches (2.2 - 3 cm).

Identification: Upperside mostly bright blue; female hindwing with orange spot at lower edge. Underside of both sexes with only 3 basal black spots. One of two eyespots at corner of outer margin is always capped with red. Very similar to the Miami Blue.

Life history: Eggs are laid singly on flower buds of host plant. Caterpillars feed on flowers and may live inside the pods, eating seeds.

Flight: Throughout the year in Florida. Adults are in reproductive diapause during the winter generation from December-April.

Caterpillar hosts: Nickerbean (Cesalpinia bahamensis).

Adult food: Flower nectar including that of Croton.

Habitat: Openings and edges of tropical hardwood hammocks.

Range: Big Pine Key, Florida and West Indies.

Conservation: Populatipon on Big Pine Key is only U.S. population and should be protected from extirpation by aerial spraying for mosquitoes.

The Nature Conservancy Global Rank: G4G5- Apparently or demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.

Management needs: Preserve habitat of caterpillar plant and nectar sources.


Glassberg, J. 1999. Nickerbean blues arrive in Florida. American butterflies 
     7(2): 22-25.

Smith, D.S., Miller, L.D. and J.Y. Miller. 1994. The butterflies of the West 
     Indies and Florida. Oxford University Press, New York. 264 pages.

Author: Paul A. Opler

Nickerbean Blue (Hemiargus ammon)
distribution map
map legend

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