Beautiful Beetles

Skyrail Nature Diary: March 2008

Beetles really are out and about at this time of the year!

Summer commonly brings out the rainforest beetles, with large numbers emerging thanks to the warm weather and lots of rain.

Beautiful and highly diverse, beetles are by far the most common type of animal on the planet.

There are up to 90,000 species of insects in Australia, and Australia’s Tropical Rainforests are home to around 28,000 species of beetles!

Beetles spend most of their lives in the form of a big, fat grub. These grubs live in tree trunks and under the ground for several years before embarking on their short lives as beetles.

Beetles have an exoskeleton, a hard outer-shell, which protects their soft bodies. Beetles also have two sets of wings – the first is the hardened elystra (protective casing) and the second, inner set is used for flying.

The Mueller’s Stag Beetle (Phalacrognathus Muelleri) is considered to be one of the most beautiful beetles in the world.

Found only in Australia’s Tropical Rainforests, the Mueller’s Stag Beetle grows up to 70mm in length and boasts a dazzling metallic green, gold and purple exoskeleton. Both the male and the female have “staghorns”, however the males are much larger, and are used in “battle” against other males to compete for females.

Another very beautiful beetle found in Australia’s Tropical Rainforests is the Christmas Beetle (Anoplognathus aureus).

There are 35 species of Christmas beetle found in Australia, all differing in appearance. The particular species found in the rainforest is a beautiful metallic gold in colour and grows up to 18mm in length.

The Christmas beetle gets its name because it tends to emerge from the ground in December and January, however these beetles can live for up to one or two years.

Another beetle commonly seen in Australia’s Tropical Rainforests is the Rhinoceros Beetle (Xylotrupes gideon).

The Rhinoceros Beetle is the largest scarab beetle found in Australia, measuring up to 60mm in length. They are shiny and black in colour and make a distinctive hissing sound when disturbed.

The male of the species has a single forked horn protruding from its head, which it uses to battle other males (much like the Mueller’s Stag Beetle).

The female Rhinoceros Beetle looks rather different to the male, as it does not have any horn at all and is often mistaken for a completely different species of beetle.

The Rhinoceros Beetle can live up to twelve months.

Pictures courtesy of Wet Tropics Management Authority