Melanodes anthracitaria

Melanodes anthracitaria Guenee, 1857
(one synonym is : Praxis corvus)
NACOPHORINI , ENNOMINAE , GEOMETRIDAE

Don Herbison-Evans ( donherbisonevans@yahoo.com )
&
Stella Crossley

(updated 13 September 2008)

Green form
(Photo: courtesy of Merlin Crossley)

This is an interesting species because the Caterpillars and the moths both have two forms. The Caterpillars can be either green or brown.

Brown form
(Photo: courtesy of Merlin Crossley)

The young Caterpillars are green with orange heads. They accepted the young leaves of:

Gum Trees ( Eucalyptus, MYRTACEAE ).

The mature Caterpillar has only one pair of ventral prolegs, with vestiges of two other pairs. The head has a flattened appearance. The body appears translucent, being either green or brown. The green form has orange spiracles, thin yellow bands between segments, a pale yellow head, and red lines across the top of its head and on the top of the anal segment. Its true legs have red claws. The brown form has pale spiracles, red between the segments, a red head, a red line around the top of the anal segment, and red true legs.

The pupal period is about nine months.

black and yellow form
(Photo: courtesy of Merlin Crossley)

The adult moths are slate grey with jet black wavy lines on the wings. One form differs from the other in having pale yellow bands on the wings. The undersides of the two forms is the same: grey-brown with a black dot in the centre of each wing. The females have a wingspan of about 5 cms. The males are smaller, having a wingspan of about 4 cms.

black form
(Photo: courtesy of Merlin Crossley)

In Melbourne, the moths come to light between August and January. The totally black form predominates in August and September.

eggs, magnified
(Photo: courtesy of Cathy Young)

The females of both forms lay green eggs in a cluster. The eggs are oval with microscopic crenulated ridges. As the eggs age, they become purplish, then brown. Their diameter is about 0.75 mm. They hatch after about two weeks. Both green and brown Caterpillars develop from eggs of the black moth. The eggs of the black and yellow moths appear to produce only green Caterpillars.

The species is found in southern Queensland, in New South Wales, Victoria, South Australia, and Tasmania.