Introduction
The Sailors, or Gliders as they are sometimes called, are all members of the genus Neptis – a large and confusing group of butterflies found across much of the world, excluding the Americas. They are noted for characteristic sailing flight, and their shared theme of white spots and bars on a black background.
The genus Neptis comprises of about 170 species, of which at least 65 occur in Africa, 40+ in the Palaearctic region ( Europe, and Asia north of the Himalayas ), 6 in Australasia, and about 50 in the Oriental region. Distinguishing the species involves careful study of the configuration of the white spots, bars and submarginal lines on both wing surfaces.
Neptis serena is found from Gambia and Senegal to Ethiopia, and south to Zimbabwe, Zambia and northern Botswana.
Habitats
This is a forest edge species, found in riparian forest, dry open woodland, and savannah / forest mosaics, at altitudes between sea level and about 1400m.
Lifecycle
In Neptis species the egg is placed at the very tip of a leaf of the foodplant, on the upper surface. It is pale green, globular, and covered in a network of hexagonal ridges from which arise 100 or more tiny spikes, giving it the appearance of a tiny sea urchin. The caterpillar spends its early instars hiding in a curled up dead leaf from which it will periodically venture out to feed.
Adult behaviour
This butterfly has a very graceful flight, riding on thermals, with periods of gliding punctuated by occasional sharp wing beats. The Sailors fly with meticulous precision, weaving in and out through the foliage and branches of trees and bushes.
Both sexes periodically alight to bask on foliage, with their wings fully outspread. Males can also be seen perching on foliage with their wings erect but held slightly apart.