Sometime ago, a mighty fine opportunity presented itself, as a particularly dreary post-monsoon day found me testing a Canon EF 180 mm f/3.5 L Macro USM lens, for a friend. The 180 mm macro was exceptionally sharp and a joy to use and I enjoyed immensely enjoyed every ioata of time spent with it.
As luck would have it, I was working with my trusty Canon EOS 5D mark III, which enabled me to increase the ISO, resulting in higher shutter speeds to compensate for the long and heavy macro which lacked image stabilization.
The advantage of the longer focal length was made apparent while zooming in on a pair of mating Common Grass Yellow butterflies, presented below for your viewing pleasure.
The shrub the butterflies were mating on was under the shade of a large tree and even though it was high noon, the light was abysmally low, which called for using a shutter speed of 1/250 s and an f/9.0 aperture to gain enough depth of field and sharpness, a feat accomplished by utilizing an ISO 2000 lens.
The Common Grass Yellow (Eurema hecabe) is a small pierid butterfly found in Asia and Africa. Amongst the commonest of our butterflies, they fly close to the ground in open grasslands and brush jungles.
The species, with its bright lemon yellow wings, bordered with blackon the upperside and dark brown markings on the underside is often very variable, particularly in case of it’s under wing markings.
The female is larger and a paler yellow, with diffused broader black markings on the upper wings, particularly on the black marginal border on the hindwings.
Adult butterflies can be often be spotted, fluttering tirelessly in parks and urban wastelands, regularly visiting flowers for nectar while the males frequently mud puddle on any available damp soil patches, in order to meet their mineral content requirement.
The species exhibits seasonal polyphenism, having a darker summer morph, triggered by long day light hours exceeding 13 hours in duration, while shorter diurnal period of 12 hours or less induces a lighter morph during the post monsoon period.
Eggs are laid singly on Abrus precatorius, Acacia spp., Aeschynomene spp., Albizzia spp. and numerous other Leguminosae, Euphorbiaceae and Cucurbitaceae species.
The Larvae are long, green, rough, cylindrical and slightly depressed, with a large head.
The Pupae are suspended by the tail end, by a moderately long band; the abdominal segments are round, but the thorax is much compressed, the wing-cases uniting to form a deep sharp keel. The head-case terminates in a short pointed snout.
The pupae, while ordinarily solitary and green, are sometimes found adorning dead branches in large numbers, during which time, having selected a suitable branch for the purpose, they acquire the colour of their background, as nearly all Pierine and Papilionine pupae are prone, to a greater or lesser degree.
The Common Grass Yellow is host to multiple strains of Wolbachia bacterium, which are well known to alter the sex ratio of the species they parasitize.