25 May 2013

Life History of the Chocolate Grass Yellow

Life History of the Chocolate Grass Yellow (Eurema sari sodalis)

Butterfly Biodata:
Genus: Eurema
Hübner, 1819
Species: sari Horsfield, 1829
Subspecies: sodalis Moore, 1886
Wingspan of Adult Butterfly: 35-40mm
Caterpillar Local Host Plant: Archidendron jiringa (Fabaceae, common name: Greater Grasshopper Tree, Petai Belalang).

A Chocolate Grass Yellow puddling on wet ground for minerals.

Another puddling Chocolate Grass Yellow.

Physical Description of Adult Butterfly:
Above, the wings are deep lemon-yellow, each with a black border which is regularly scalloped and deeply excavated between veins 2 and 4 in the forewing. Underneath, the wings are yellow with freckled brown spots. There is one cell spot on the forewing which has its apex entirely in dark brown. Males have a brand lying along the cubital vein on the forewing underside.

A Chocolate Grass Yellow taking nectar from Syzygium flowers.

A Chocolate Grass Yellow visiting a tiny flower for nectar.

Field Observations of Butterfly Behaviour:
Chocolate Grass Yellow is common in both nature reserves and urban parks in Singapore. The adults can be readily seen fluttering tirelessly in these areas. They are easily confused with other Grass Yellow spp. while in flight, but their distinctive brown forewing apical area immediately set them apart when they come to a perch. They regularly visit flowers for nectar and puddle on wet grounds for minerals.