28 February 2015

Life History of the Grand Imperial

Life History of the Grand Imperial (Neocheritra amrita amrita)

Butterfly Biodata:
Genus: Neocheritra Distant, 1885
Species: amrita
C & R Felder, 1860
Sub-species: amrita C & R Felder, 1860

Wingspan of Adult Butterfly: 36-40mm
Caterpillar Local Host Plant:
To be identified.

Physical Description of Adult Butterfly:
On the upperside, the male is dark brown with inner and basal halves of both wings in shining blue. The female is almost entirely brown. Both sexes have whitened tornal areas in the hindwing bearing large black quadrate marginal and submarginal spots. On the underside, both sexes are mainly yellowish orange but white in the lower half of the hindwing. Black post-discal striae are present in the tornal half of the hindwing. In the forewing, the basal part of vein 12 is not black (this is a key characteristic for distinguishing the Grand Imperial from the Great Imperial). In the hindwing, there are whitish tails at the end of veins 1b and 2 with the one at vein 1b much longer (about 2.5x as long as the one at vein 2) and fluffy in appearance.

A sunbathing female Grand Imperial displaying its upperside.

Field Observations of Butterfly Behaviour:
This species is rare in Singapore. The handful of sightings took place mainly in the catchment reserves, as well as the offshore island, Pulau Tekong. The adults have a graceful flight and typically perch with its wings closed upright between flights. In sunny weather, however, they have been observed to sun-bathe with wings fully open. They are sometimes sighted while hanging around a flowering plant for their nectar intake.