Introduction
The genus Pirdana is endemic to the Oriental region and comprises of 4 known species, albicornis, hyela, distanti and fusca, the last of these being discovered as recently as 1983.
All Pirdana species have dark uppersides with a metallic bluish-green sheen, and golden-yellow scales around the tornus on the hindwings. Additionally they all have deep ruby eyes.
The commonest and most widespread species is hyela which is found from Myanmar to Sulawesi. P. albicornis is endemic to Borneo, and fusca is endemic to Samar in the Philippines.
Pirdana distanti is found in West Malaysia, Sumatra and Borneo.
Habitats
This is a very rare species which is confined to primary rainforest at altitudes between about 100-300 metres. The individual depicted above was photographed in dark swampy forest near Kuala Tahan in Taman Negara national park.
Lifecycle
The only details I have of the early stages are that the larva is “green with black markings” and feeds on Dracaena and Cordyline ( Agavaceae ).
Adult behaviour
The butterflies are probably mainly crepuscular in habit. The butterfly depicted was disturbed from rest in the late afternoon. It had a rapid whirring flight and was very alert and difficult to approach – while attempting to follow it I managed to trip over a tree root, slide down a slope into a muddy pool, and gather a few cuts and bruises, losing sight of the butterfly on several occasions !