Saturday, 17 November 2018

Tidbinbilla Moths

Emperor Gum Moth Opodiphthera eucalypti  (c 15 cm wingspan)

I was out at Tidbinbilla Nature Reserve last week helping with a moth survey organised by Glenn Cocking and Suzi Bond for their book on moths of the Australian Capital Territory. The site was well sheltered beneath tall eucalypt trees and I managed to photograph about a dozen species. Here is a small selection of the ones I photographed. It is the colours and form that appeal to me. Knowledge of these species is so sparse that I cannot fill out the text to tell more about them, especially their lifestyles, habitats and foodplants. Hopefully that will all be in the book.

Melanodes anthracitaria dark phase (c 5 cm wingspan)

This rather ordinary moth is worth a mention because it occurs in two colour forms; a dark all grey phase, and light phase of grey blotched with creamy/yellow.

Melanodes anthracitaria light phase

Hypobapta sp. from above (c 4 cm wingspan)

I like to see the moths' tiny faces, antennae and those big round eyes. 

Hypobapta sp. from the side/front

Praxis porphyretica (c 4 cm wingspan)

Callitera rotundrata (c 4 cm wingspan)

Cleora sp.  (c 4 cm wingspan)

What wonderful antennae.

Nisista sp. (c 4 cm wingspan)

This species looks so much like a rolled-edged leaf lying on the forest litter.

Endotricha ignealis (c 2 cm wingspan)

This species seems deliberately to hold its forequarters up on its long legs, and its great long antennae are swept over its back. 

Endotricha ignealis 

Parepisparis lutosaria (c 7 cm wingspan)

Finally, this was my favourite find of the night, magnificent colour and form.

Saturday, 10 November 2018

Small Ant-blue

Acrodipsas myrmecophila

Small Ant-blue butterflies are indeed small.

Although when they fly in swarms like this one, in which there were of over a hundred individual males, they are spectacular.

This is the tree they were flying around, a small Blakeley's Red Gum sapling, with some dead wood lying around, in an open grassy woodland on the edge of the suburbs. The butterfly is a rare resident in the Canberra area, and is uncommon or very localised throughout its range from Victoria to southern Queensland.

Here a group of four adults (all male) have newly emerged from the ant nest they have developed within and overwintered as larvae. The ants are Coconut Ants Papyrius nitidus, and the butterfly larvae feed on their larvae. The ants build their nests in dead wood lying on the ground and in the base of the saplings.

Once their wings are fully extended they begin flying around the nest trees and perch on the branches and leaves, ever watching or smelling for females.

When fresh, their wings have a delicate fringe of scales.

When a few days old, the fringes are tattered and the wings themselves become chipped and ragged. The metallic blue of the bronze upperwing shows in this photo.

Two males perched on my watch as I was photographing the flock. They seldom sit with their wings open for more than a few seconds.

The females were scarcer and seemed to mate as soon as they could fly. The next time they became obvious was when they were seeking a crevice or shady piece of bark at the lower parts of a sapling to lay their eggs in.

I never saw a female sit with her wings open and this one only shows a glimpse of the bright metallic blue of her upperwing.

Once they have laid their eggs the females die. Or in this case are immediately killed and dismembered by the ants. How did the ants know to let her lay her eggs before attacking her. They were in attendance all the time she was laying. The blue of her wings is more easily seen now.

The males probably live for a week of so, competing to mate with a female, but they too can become prey. This one flew into a spider's web, she can be seen top right. Other males were caught by birds, such as Noisy Miners which had a nest in the ant-tree.

The whole flying season probably only lasts for a one or two weeks. Then once the adults have died, the species continues as several instar stages within the ant nest until the next generation emerges the following year. But what do the ants gain from the partnership? or are they simply conned by some pheromone emitted by the butterflies and larvae?