03 February 2013

Life History of the Yellow Flat

Life History of the Yellow Flat (Mooreana trichoneura trichoneura)

Butterfly Biodata:
Genus: Mooreana Evans, 1926
Species: trichoneura C & R Felder, 1860
Sub-Species: trichoneura C & R Felder, 1860
Wingspan of Adult Butterfly: 32-36mm
Caterpillar Local Host Plant: Mallotus paniculatus (Euphorbiaceae, common name: Turn-in-the-wind).

A newly eclosed female Yellow Flat showing its underside.

Physical Description of Adult Butterfly:
Both sexes are alike in coloration and markings. Above, the wings are dark brown with veins strongly dusted in white or pale yellowish brown. The forewing bears a number of round and stroke-shaped hyaline spots in the outer half of the wing. The hindwing has a large yellow tornal area and has yellow coloured cilia extending up to vein 6. Underneath, the forewing is dark brown with the same set of spots as above. The veins are not marked in white or pale brown. The hindwing is predominately white from the dorsum to vein 6, with the white coloration diffusing into spaces 7 and 8. The male has a hair tuft on its mid- and hind tibiae.

Close-up views of the legs of both sexes of Yellow Flat, the hair tuffs on the mid- and hind tibae of the male are visible.

Close-up view of the front part of a Yellow Flat taking nectar from Lantana flowers.

Field Observations of Butterfly Behaviour:
C&P4 describes Yellow Flat as being rare in the forested plain in Malaya. This holds true for this newly discovered species in Singapore (see this blog article for a report of the discovery in November 2012) as there has only been a handful of field sightings in the few months since the first sighting. The adult has a strong preference for dark and shady area, and rarely does it venture to sunny spots for sunbathing. The adults are fast and strong flyers and have the habit of perching with their wings opened flat.