(one synonym : Acidalia recessata Walker, 1861)
STERRHINAE, GEOMETRIDAE, GEOMETROIDEA
The body of this Caterpillar is long and thin. When resting, it stands erect, but with a bend and twist in the front half of the body. A group of these caterpillars standing side by side on their food plant look like a minature of the entwined snakes that were reputed to form Medusa's hair.
The caterpillar is fawn with small lateral dots each side near the front of the abdomen. Early instars are striped, but the stripes are only vague on later instars. It is a looper, with only one pair of ventral prolegs. The caterpillars have been found on:
The caterpillars grow to a length of about 2 cms.
They pupate in the leaf litter.
The adult moths range in colour from pale green to yellow.
Each wing often has a small black central spot, and is traversed by brown lines, with the inner one wider than the others. The hindwings have an angled outer margin. When at rest, the moths hold their wings outspread so that these transverse lines continue unbroken across all four wings. The moths have a wing span of about 2 cms.
In captivity, an adult female laid rows of ellipsoidal white eggs on the flat surface of a Wattle phyllode (which was odd as the caterpillars refused to eat it). Each egg was twice as high as it was wide and had microscopic corrugated ribs. The eggs were spaced so that they did not touch each other. As they approached hatching, they developed red spots.
The species has been found in Australia in
Moths of Victoria: Part 3,
Waves & Carpets - GEOMETROIDEA (C),
Entomological Society of Victoria, 2011, pp. 6-9.
Catalogue of Lepidoptera Heterocera,
List of the Specimens of Lepidopterous Insects in the Collection of the British Museum,
Part 23 (1861), p. 776, No. 239.
(updated 11 November 2013, 10 June 2018, 13 October 2020)