Saturday, 29 October 2011

A clique of Clicks

Everyone is familiar with click Beetles. They seem to occur everywhere. Wherever a light is burning in the temperate and tropical world you can expect to see a Click Beetle of some description. Several dozen species occur in the north Queensland rainforests. They range in size from a few millimetres to 45 mm or so. They are mostly dull-coloured but there are notable exceptions like Paracalais clicks that have a camouflage pattern similar to the pattern lichens present on rainforest trees.

The body shape is characteristic and the angles of the thorax are produced. Ventrally there is a spine-like process that fits into a groove. This causes the "click" that allows the beetles to flip when it is disturbed or when they inadvertently fall on their backs. The body integument is very tough and you frequently see birds attempting to "crack" larger beetles, usually with little success.

Click beetle larvae live in the soil and are often called Wireworms. Several species are economically important because of their depredations to roots of crops like wheat and other grasses. Adult clicks live in foliage; some are predaceous, others feed on plant material.

it is estimated there are 70 genera in Australia with 667 described species. Andrew Calder has produced a monograph on the Australian fauna.


A Click Beetle, Paracalais sp. in a typical position-on its back.

The same beetle right-side up.
A close look at the colour pattern revels that it comprises modified hairs or scales.

A large specimen of Lanelator sp. Note the sharp angles of the thorax, a characteristic of the Elateridae.

Reference
Calder, A. E. 1996. Click Beetles Genera of the Australian Elateridae (Coleoptera). Monographs on invertebrate Taxonomy, Vol. 2. CSIRO Publishing, Collingwood, Vic.

1 comment:

Susan Bishop said...

Hello David,

We just found what looks like a Paracalais sp. Click Beetle. I have been living in North Queensland for 19 years and have not seen one like this before (about 5cm and bark patterning). Is it rare? I took some photos and some film of it clicking.
A lovely little fellow.

Sue