Garden Weevil

Phlyctinus callosus

Family: Curculionidae

Order: Coleoptera

Description:

Adult

Nocturnal and hides in the ground during the day.

Colour - Dull grey. Pale V marks near rear.

Body - Slightly flattened. 5 mm long, 2 mm wide.

Wings - 2 Pairs. Front wings modified to form hard protective cases (elytra) for rear wings. When at rest they meet in a straight line down the centre of the back. Rear wings membranous and folded both lengthwise and across so they fit under their protective cases. When in flight the elytra are held at an angle and the rear wings beat rapidly. Rear wings may be reduced or absent in some species. Wing-span up to 200 mm. Both pairs attached to the hind body.

Mouthparts - Chewing. Pointing forward.

Antennae - 7-11 segments.

Legs - Rear legs larger than front legs. Feet (Tarsi) have 3-5 segments with 1 or 2 claws on the end segment.

Head - Rigid. Large rounded compound eyes.

Thorax - Front segment associated with head to form distinct fore body. Front segment covered by a hard plate (pronotum). 2 rear segments fused and associated with the abdomen to form hind body.

Abdomen - 10 segments in male, 9 in female. Often only 8 can be counted by eye. Spiracles on segments 1-7 and often on 8 also.

Egg - Usually simple and ovoid.

Habits - Can't fly when cold.

Larva -

Colour - white with darker head.

Body - No legs, C shaped. 5 mm long, 2 mm wide.

Mouthparts - Chewing. Transverse action.

Antennae - 1 segment.

Legs - Has no legs or 6 legs. 5 segments.

Head - Usually a hard capsule. No ridges on forehead.

Thorax - No functional spiracle on middle segment.

Abdomen - 8-11 segments. No prolegs. Spiracles on segments 1 to 8.

Habits -

Pupa -

Biology:

Life Cycle:

Eggs usually laid near food source for larva. Larva hatch and feed underground on roots.

Habitats:

Origin and History:

Distribution:

Significance:

This weevil, introduced from South Africa, has damaged carrots when the larva chewed holes into the carrot below ground level (Similar to carrot weevil). The adult attacks garden plants. It seems to prefer the more succulent species and damage is often patchy. The adults chew deep rounded holes, scattered over the leaf surface.

Management and Control:

Cultivation before planting. Insecticides.

Related Species:

Similar Species:

References:

CSIRO. The Insects of Australia. Melbourne University Press. (1991) p562, 682.

Victorian Department of Agriculture. Insect Bulletins. p21.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.