PEST
 
   NAME
     Longicorns, Long Horn Beetles
     Various Longicorn Species
 
   ORDER
     Coleoptera
 
   FAMILY
     Cerambycidae

Description of the Pest
This is a large group of beetles with over 1,000 species that commonly have two long and conspicuous antennae and square shoulders. They may be large or small, dull or brightly coloured beetles. The creamy-white fleshy lava has reduced legs and taper from the thorax. Both the Lava and adult beetle has chewing mouth parts. 
These insects have a Holometabolous life cycle, ie. When metamorphosis is observed during the pupal stage.

Appearance of the Pest
The adults lay eggs in wounds or in damaged areas by active borer larvae. The Larvae bore large circular tunnels in the sapwood for many months, which become packed with frass. The damage is evident with cracked bark, surrounded by sawdust and the appearance of gum oozing out of the wound. 
Some species ringbark twigs or trunks and the larva pupate in the plant.
The adult emerges from ‘emergence holes’ and may chew bark or foliage but generally the damage is insignificant.

Auger Beetle (Bostrycnopsis jesuita) is another insect that produces a tunnel boring, plump white larva. The adult grows to 18mm long and its thorax forms an outgrowth that extends over its head making the beetle to always look down.

Pittosporum Longicorn (Strongylurus thoracicus) is brown with white spots on either side of the thorax with long antenna and is up to 30mm long. It lays creamy legless lava that feed on the sapwood of small branches in Pittosporum species by forming rounded tunnels.

Twig Girdling Longicorn (Platyomopsis humeralis) is a dark coloured beetle with anatine the same length as its body up to 20mm long. The wing covers may have stripes or dots and the mandibles are strong arranged at right angle to the body. It feeds on bark forming rings around branches or small twigs.

Period of Activity
The adults are active from spring to summer and are found throughout Australia from tropical to temperate regions.

Susceptible Plants
Many ornamental and Australian native trees, shrubs or climbers, including Eucalyptus, Pittosporum, Ficus and Vitis species. The larva also attacks recently fallen timber or existing dead plants. 

Banksia species are attacked by the Banksia Longicorn (Paroplites australis) which is a reddish brown beetle to 50mm long with equal length antennae and produces a yellowish fleshy (grub-like) lava, that is legless and tapers towards its tail. It tunnels into the hardwood and can cause severe damage.

Eucalyptus are attacked by the Giant Longicorn (Eurynassa odewahni) which is a large beetle up to 80mm long with equally long antennae and produces a plump legless white (grub-like) lava, that are ribbed and tapers towards its tail. 

Grevillea robusta, Melia azedarach and Brachychiton populneus are attacked by the Auger Beetle larva.

Damage Caused
The larva eats away the sapwood and may tunnel deep into the timber creating open wounds on the trunks and in some cases ring barking the plant. Certain species graze only on the bark and associated wood such as The Twig Girdling Longicorn and the result of the damage is not evident well after the insect has moved on. Branches that have been attacked are weakened and snap off during high winds. 
The Auger Beetle eats circular holes through the sap wood and heart wood reducing the structural strength of the tree. 

Cultural Control
Stressed plants are commonly attacked and action should be taken to invigorate the plant with additional watering and fertilising. It may be possible to kill the larvae with a piece of wire and areas that have been damaged should be treated with tree surgery techniques to mend the wound.

Biological Control
Beetles and larva are eaten by birds and lizards but are not an effective control.

Chemical Control
There is no effective chemical control.