Strymon acis

(Drury, 1773)

Bartram's scrub-hairstreak, Caribbean Scrub-Hairstreak

Strymon acis is a small lycaenid with a wingspan of 22–29 mm, occurring in southern Florida and the West Indies. The S. a. bartrami, restricted to southern Florida, is federally listed as Endangered under the United States Act. The is tightly associated with pine rockland and depends on Croton linearis as its larval plant.

PapilioAcisDrury1773OD by Dru Drury. Used under a Public domain license.

Illustrations of Exotic Entomology Thecla acis by Plates: Dru Drury (1725–1803). Text: John Obadiah Westwood (1805–1893). Used under a Public domain license.

Illustrations of Exotic Entomology I 01 by Plates: Dru Drury (1725–1803). Text: John Obadiah Westwood (1805–1893). Used under a Public domain license.

Pronunciation

How to pronounce Strymon acis: //ˈstraɪmɒn ˈeɪsɪs//

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

Identification

Distinguished from other hairstreaks by the combination of dark gray upperside, pale gray underside with white and black linear markings, and the distinctive hindwing tails (one long, one short). The two white spots near the wing base on the underside are additional diagnostic characters. The Florida S. a. bartrami is geographically isolated from other Strymon in the region.

Images

Habitat

Openings in pine woods, specifically pine rockland in Florida. These depend on regular fire events for maintenance. The bartrami is restricted to the imperiled pine rocklands of southern Florida.

Distribution

Southern Florida (United States) and the West Indies (including Cuba). The nominate S. a. acis occurs in the West Indies; S. a. bartrami is to southern Florida; S. a. casasi occurs in Cuba; S. a. mars has a broader distribution.

Seasonality

In Florida, are active from February through November with three to four periods () during this span.

Diet

Larvae feed on flower buds and young fruits of Croton linearis (narrow-leafed croton). feed on nectar from flowers of narrow-leafed croton and shepherd's needle (Scandix pecten-veneris).

Host Associations

Croton linearis - larval plantLarvae feed on flower buds and young fruits; young caterpillars also consume upper leaf surfaces, flowers, and fruit
Scandix pecten-veneris - nectar source
Trichogramma sp. - Documented specifically for S. a. bartrami

Life Cycle

are laid singly on flower stalks of plants. Young caterpillars feed on upper leaf surfaces, flowers, and fruit. Older caterpillars feed exclusively on leaves. Multiple per year in Florida (three to four ).

Behavior

Males of related Strymon (including S. melinus) exhibit , flying to elevated terrain to defend perches and seek females. This mating strategy may occur in S. acis but has not been specifically documented.

Ecological Role

of native plants including its larval Croton linearis. Serves as host for in the Trichogrammatidae. A herbivore tightly linked to pine rockland dynamics.

Human Relevance

The Florida S. a. bartrami is federally listed as Endangered, making it a focus of conservation efforts. loss from development (including the 2017 Walmart/Coral Reef Commons controversy in Miami-Dade County) poses severe threats. The is an indicator of intact pine rockland .

Similar Taxa

Strymon melinusGray shares gray coloration and tailed hindwings, but has broader distribution, different plant associations, and lacks the specific wing pattern of two basal white spots
Strymon rufofuscaOther hairstreaks in the may overlap in range but differ in wing pattern details and associations

More Details

Conservation status

S. a. bartrami was listed as Endangered in 2014. Critical designation and ongoing legal battles (including 2017 litigation by Center for Biological Diversity) reflect severe habitat fragmentation in Miami-Dade County.

Fire dependence

The pine rockland requires periodic fire for maintenance; suppression or alteration of fire regimes threatens both the and its plant.