27 April 2013

Life History of the Plain Banded Awl

Life History of the Plain Banded Awl (Hasora vitta vitta)

Butterfly Biodata:
Genus: Hasora Moore, 1881
Species: vitta Butler, 1870
Subspecies: vitta Butler, 1870
Wingspan of Adult Butterfly: 40-45mm
Caterpillar Local Host Plant: Spatholobus ferrugineus (Family: Fabaceae)

A Plain Banded Awl perching on the underside of a leaf.

A Plain Banded Awl visiting a flower of the Singapore Rhododendron.

A Plain Banded Awl taking nectar from an Ixora flower.

Physical Description of Adult Butterfly:
Adults are rather large in size with pointed forewing apex and markedly lobate hindwings. Above, the wings are dark brown. Both sexes have one small hyaline subapical spot in the forewing, with the female having two larger hyaline spots in spaces 2 and 3 in addition. There are no cell spots, and the male does not have a discal stigma on the forewing. Below, both sexes are pale brown with a purplish sheen in fresh specimens. The hindwing has a prominent white and outwardly diffuse discal band. The inner half of the hindwing has a greenish glaze, more so in the male than in the female.

Field Observations of Butterfly Behaviour:
This species is moderately rare in Singapore. The adults have been sighted in both nature reserves and urban parks and gardens, typically during the dawn and dusk hours of a day. They have the habit of visiting flowering plants for nectar and puddling on damp patches for minerals. As with other Awl spp., the fast flying adults have a habit of resting on the underside of a leaf or other plant parts.