Introduction
The 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.
About 580 species are placed within the tribe Pyrgini.
The genus Ouleus comprises of 11 species, all confined to the neotropical region. Three species – bubaris, calavius and fridericus reach as far north as southern Mexico, and two others – negrus and cyrna are found in Panama, but the remainder are restricted to the South American mainland.
Ouleus fridericus is the most widespread member of the genus, its 7 subspecies being distributed variously from Mexico to Bolivia.
Habitats
This species occurs in rainforest, cloudforest and humid deciduous forest habitats at altitudes between sea level and about 1200 metres.
Lifecycle
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 herbaceous 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.
Adult behaviour
The butterfly is usually encountered singly, and is usually observed when basking in full sunshine on the foliage of bushes or herbaceous plants. I have not recorded males mud-puddling or visiting bird droppings.