Australian Wildlife

  Powderpost beetle (Lyctus brunneus)

Powderpost beetle | Lyctus brunneus photo
Powderpost beetle

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The Powderpost beetle is a dark brown or reddish brown shiny beetle, with the thorax usually appearing darker than the elytra. The body is flattened and elongated. The antennae are about the same length as the thorax , with the end segments forming a club shape. The elytra have a several ridges along the length. Larvae are cream c-shaped grubs with a brown head and light brown oval spots on the sides of the body. The bore holes of emerging adults are 1.5mm to 2mm in diameter.

length to 7mm

The Powderpost beetle is a pest beetle attacking the sapwood of hardwood tress such as Oak, Elm, Ash and Eucalypt. Softwoods are not attacked. The heartwood of hardwoods is not infested. Most attacks take place in logs or sawn timber drying at the sawmill. Signs of infestation may not be seen until the timber has been used and adults begin to emerge. If left unchecked, the whole infested area can be reduced to powder leaving only a thin crust of wood on the outside. Small piles of frass like sawdust may be seen where adults have emerged or galleries have broken through the surface of the wood.

The female beetle lay about 70 eggs into the open pores of the sapwood., with usually up to 3 eggs per pore. The eggs hatch after about 14 days and the larvae feed on sapwood starch taking 2 to12 months to mature depending on temperature. The larvae pupate near the surface of the wood and the adult beetles bore through the timber surface leaving a round hole one to two millimetres in diameter.

Common Name:Powderpost beetle