''Phaeostrymon alcestis'', the soapberry hairstreak, is the only

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of the gossamer-winged butterfly

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Phaeostrymon''. It is found in southwestern United States and Mexico.

References

Eumaeini Monotypic butterfly genera Lycaenidae genera Taxa named by William J. Clench {{Eumaeini-stub