Butterflies of the
Amazon and Andes
Family - HESPERIIDAE
subfamily - PYRGINAE
Tribe - PYRGINI
Antigonus decens, male, Rio Madre de
© Adrian Hoskins
Pyrginae, popularly known as Flats or Spreadwings, are a
cosmopolitan subfamily distributed across temperate and tropical
habitats throughout the world. In the Americas there are 990
species, of which about 580 are assigned to the tribe Pyrgini.
The genus Antigonus
comprises 9 small to medium sized species, characterised by having a
pointed fw apex, slight concavities in the outer margins of fore and
hindwings, and a habit ( shared with several other Pyrgine genera )
of holding the forewings such that the apical area is folded
downwards at an angle of about 30 degrees.
occurs throughout the lowland rainforests of Brazil, Peru and
This species appears to be confined to lowland rainforests at
altitudes from sea level to about 500m.
The lifecycle appears to be unrecorded. Generally, Pyrgine
butterflies lay their eggs singly on either the upperside or
underside of leaves. The larvae are typically dull green or
brownish, with thin longitudinal lines along the back and sides, and
with black shiny heads. They feed typically on low growing plants,
but a small percentage feed on the leaves of bushes or trees. The
pupae are usually dark and smooth, with the wing cases in a
contrasting tone or colour. They are normally formed within silken
tents formed by spinning together the leaves of the foodplant.
My only observations of this
attractive little skipper have been of male singletons visiting
sandbanks. In such situations they imbibe dissolved minerals from
algae-covered rocks or damp sand, particularly in areas soaked in
urine. When not feeding they sit on the leaves of sedges or other low
herbage, with wing tips downfolded in the manner typical of the genus.