Jewel Bugs (Family Scutelleridae)

Adult Hibiscus harlequin bug guarding eggs Female Hibiscus Harlequin Bugs guard their eggs

Jewel Bugs have broad rounded bodies with an undivided shield covering the whole abdomen. Jewel bugs get their common name from their bright colours. Jewel Bugs have the scutellum expanded to cover the whole abdomen and both pairs of wings, leading to their other common name, Shield-backed Bugs. Australian jewel bugs suck plant sap and feed on a broad range of seeds, either while they are still attached to the plant, or after they have fallen to the ground. In Australia, some are known as Harlequin Bugs, a common name used for several other sorts of bugs elsewhere in the world.  There are 25 Australian species of jewel bugs in the Family Scutelleridae.

Hibiscus Harlequin Bug
Tectocoris diophthalmus

The Hibiscus Harlequin Bug sucks sap from hibiscus plants, bottle trees and related species. Its main foodplant is the native Beach Hibiscus (Hibiscus tiliaceus). It is also a minor pest of cultivated cotton, a member of the hibiscus family Malvaceae, leading to its other common name, the Cotton Harlequin Bug.

Hibiscus Harlequin Bug nymphs are often a different colour to the adults

Biology

Females lay clusters of eggs around twigs and guard them until they hatch. The nymphs are often a different colour to the adults. The Hibiscus Harlequin Bug is found in coastal dunes, rainforest, open forest and gardens in northern and eastern Australia, New Guinea and some Pacific islands.

Identification

Length about 15 mm. The body is rounded and convex. Its colour varies, from pale orange to heavily patterned with metallic green, blue and red.

Mallotus Harlequin Bug
Cantao parentum

Mallotus Harlequin Bug, Cantao parentum Mallotus Harlequin Bug, Cantao parentum

The Mallotus Harlequin Bug sucks the sap of Mallotus trees (Green or Red Kamala) in dry rainforest in south-east Queensland and northern New South Wales. During winter, large numbers of adults cluster together and may remain inactive for two to three months. The species name ‘parentum’ refers to the fact that the females demonstrate parental care by guarding the eggs and young nymphs from predators.

Identification

Length about 20 mm. This species is similar to the Hibiscus Harlequin bug but has a more elongated body. It is orange with two black spots on the thorax and eight spots on the enlarged, shield-like scutellum.

Green Jewel Bug
Lampromicra senator

Green Jewel Bug, Lampromicra senator

Biology

The Green Jewel Bug forms non-feeding clusters during hot dry periods especially along creeks, spreading out to feed on many plants from ferns and figs to Lantana when conditions improve. It occurs in tropical and subtropical Australia, extending as far south as Wollongong in New South Wales.

Identification

Length 9 to 14 mm. The Green Jewel Bug is extremely variable in coloration, ranging from metallic green to purplish-blue. Some specimens have an orange stripe across the shield-like scutellum.

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