Tonica species

Tonica species
DEPRESSARIIDAE, GELECHIOIDEA

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

early instar
(Specimen: courtesy of Fred Swindley)

This Caterpillar is initially pale brown with a dark brown head, prothorax, true legs and tail.

caterpillar inside its borehole
(Specimen: courtesy of Fred Swindley)

Later the caterpillar becomes brown, and develops rows of dark brown tubercles along the back, and has a flattened abdomen towards the tail.

(Photo: courtesy of Fred Swindley)

It bores into and feeds inside the growing shoots of:

Flame Tree ( Brachychiton acerifolium, STERCULIACEAE ).

Beads of gum and frass at bore hole entrance
(Specimen: courtesy of Fred Swindley)

The plant appears to respond by secreting a gelatinous sap to heal the wound, but the caterpillar collects this inside its borehole, rolls it into little round beads, and deposits them at the entrance to its borehole, together with frass.

last instar
(Photo: courtesy of Fred Swindley)

The caterpillar pupates without a cocoon on the outside of the plant. The pupa is camouflaged in various shades of brown. It stands on its tail, but it is very curved. When disturbed, the pupa curls down to nearly touch the substrate, and then flicks back up again.

(Specimen: courtesy of Fred Swindley)

The adult moth has wings which look as though a semi-circular piece has been taken out of the termen. It also has raised areas on the wings of loose scales.

Female
(Specimen: courtesy of Fred Swindley)

The males are smaller than the females. The males have a wingspan of about 2 cms. The females have a wing span of about 2.5 cms. The male that we raised was nearly white, and the female fawn coloured. Both had a little black mark on the tip of each fore wing. They both rest with its long mouth parts extended out in front of the head.

(Specimen: courtesy of Fred Swindley)

The irregular shape makes a very effective camouflage on the irregular bark and stems of the food plant.

Male
(Specimen: courtesy of Fred Swindley)

Our specimens were obtained from a tree in West Ryde, Sydney. The Cockatoos were very active in this tree, tearing the twigs apart. We suspect this damage was to get to the Tonica larvae inside.

Twig damage caused by Cockatoos,
which were probably in search of Tonica Caterpillars.
(Specimen: courtesy of Fred Swindley)