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.
The tribe Eudamini includes 44 genera in the Americas, amongst which are the Long-tailed Skippers Urbanus, Chioides and Aguna; and other familiar genera including Phocides, Autochton, Astraptes Pellicia and Polythrix.
There are several different genera of ‘tailed’ skippers occurring in the neotropical region including Urbanus, Aguna, Polythrix and Typhedanus. They can be distinguished from each other by the wing venation and by the configuration of the hyaline spots on the forewings. Additionally, in Urbanus the outer margin of the forewing is convex, but in the others it is concave to a greater or lesser degree.
There are 14 known Polythrix species. The butterflies are characterised by having a series of small hyaline ( transparent ) windows in the forewing, which follow the same general layout as in caunus. The wing fringes of Polythrix species are white, whereas in the other tailed genera they are either chequered or pale brown. The tails of Polythrix tend to be stubbier than in the other genera.
Polythrix caunus is found in Brazil, Ecuador and Peru.
Habitats
This species occurs in tropical rainforest at altitudes between about 300-1000m.
Lifecycle
The caterpillars feed on various trees and shrubs in the family Leguminosae including Muellera, Senna, Toluifera and Pterocarpus.
Adult behaviour
Males are usually encountered singly amidst mud-puddling aggregations, feeding and basking with their wings outspread.
