Butterflies of the Rainforest

Skyrail Nature Diary: March 2012

Butterflies of Barron Gorge

There are quite a few of these beautiful critters fluttering about at the moment. Almost everybody knows what a butterfly looks like but it’s still worth having a closer look at what exactly constitutes a butterfly. First of all, a butterfly is an insect. There are a number of animals that superficially look like insects, e.g. spiders, centipedes, millipedes and crustaceans. The giveaway features include: 1. Three body parts (head, thorax and abdomen). 2. Three pairs of legs. 3. One pair of antennae. 4. Three pairs of mouthparts, the last pair fused. 5. Two pairs of wings on the thorax (can be reduced or missing).

Butterflies belong to a large group of insects that have what is called a complete life cycle. This means they have four stages: egg, larva, pupa and imago. The larva looks completely different to the adult (imago) and generally has a different lifestyle. Larvae normally don’t have any wings. Butterfly larvae are known as caterpillars and most of all look like grubs with multiple legs. A caterpillar’s main job is to eat and grow. When they reach a certain size the larva turns into a pupa, a dormant stage where the larva’s body is transformed into that of the adult (imago). The imago’s job is to mate and disperse their offspring, hence the wings and well-developed eyes. Butterflies have club like antennae and a curled up mouth shaped like a double straw used to feed on nectar to fuel their flight. The wings superficially look like two wings but there are in fact four wings. The front and back wings on each side are linked together with tiny hooks and the surface of the wings are covered with thousands of tiny scales that reflect light. This gives the wings their distinct colour patterns. After mating the males die, while the female flies around and distributes her eggs according to the larvae’s needs. Once that is done she dies as well.

Ulysses Butterfly (Papilio ulysses) is without a doubt the most well-known butterfly in North Queensland. It is especially associated with Dunk Island thanks to Edmund Banfield’s book "Confessions of a Beachcomber". The wings of the Ulysses Butterfly are metallic blue with black edges and trailing "swallowtails". These butterflies are the only ones that fly above the canopy and out in the wide open. They often surprise people by zooming around rather than fluttering butterfly style. They are attracted to reddish and pinkish flowers and seem to have a certain fondness for the introduced lantana. Despite this they always lay their eggs on the Pink Evodia (Melicope elleryana: Rutaceae), a fast growing lowland tree tolerant of wet conditions.

Cairns Hamadryad (Tellervo zoilus) is a tiny butterfly that is often overlooked despite it being one of the most common butterflies in the Cairns region. The wings are rounded and dark brown with white patterns. The front wings have four white spots each while the back wings have one large conspicuous white patch each. These butterflies are unusual in having yellow eyes, one of two butterflies in Australia to have this colour. They are the sole Australian representative of an ancient family now found in South America. They lay their eggs on the Velvet Silkpod Vine (Parsonsia velutina: Apocynaceae).

Cairns Birdwing (Ornithoptera priamus) is one of our most stunning butterflies and the second largest in the world, second only to the Alexandra Birdwing of New Guinea.  The two sexes are completely different. The larger female has large brownish wings with white dots and the body is large and plump and coloured red and yellow. The less commonly spotted male has metallic green wings with black patches and a narrow yellow abdomen. This amazing butterfly’s courtship is a wonder to behold and is rarely spotted. The male circles backwards around the female from front to back in midair. The caterpillars are equally spectacular. Apart from being a mix of green and yellow they are covered in large black spines all over. Cairns Birdwing lays its eggs on Native Dutchman’s Pipe Vine (Aristolochia tagala: Aristolochiaceae). These butterflies are regularly spotted at Red Peak, especially the females.

by Tore Linde, Ranger, Skyrail