Butterflies of the
Amazon and Andes
GODMAN & SALVIN, 1895
Family - HESPERIIDAE
subfamily - PYRGINAE
Tribe - PYRGINI
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
About 580 species are placed within the tribe
Sostrata is closely allied to
Quadrus. These genera comprise a total
of about 45 small species, characterised by having a series of tiny
transparent marks on their forewings, and a peppering of metallic
blue scales overlaid on a dingy brown ground colour.
Sostrata pusilla is
distributed from Nicaragua to Bolivia. There are 2 subspecies -
pusilla rangers from Nicaragua to
northern Ecuador, while pulsa occurs in
southern Ecuador, Peru and Bolivia.
This species occurs in rainforest and cloudforest habitats at
altitudes between about 200-1000m.
The lifecycle appears to be unrecorded. Generally, Pyrgine
butterflies lay their eggs singly on either the upperside or
underside of leaves. The caterpillars 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
herbaceous plants, but some 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.
The butterfly is usually
encountered as solitary males. They are active mainly in the early
afternoon when they can be seen basking on foliage or logs.