About Shield-backed Bugs

Scutelleridae are known as Shield-backed Bugs, as the shield hiding the wings (scutellum) is continuous, not divided. Because they are usually brightly colored, they are also known as Jewel Bugs. These insects are plant suckers, closely related to stink bugs and may also produce offensive odours when disturbed.

Cotton Harlequin Bug Tectocoris diophthalmus. Photo: Robert Whyte

Cotton Harlequin Bugs

Cotton Harlequin Bugs feed on many plants in the hibiscus Malvaceae family, including ornamental hibiscus species and cotton. The bug feeds mostly on young shoots, piercing the stems and sucking the sugar-rich juices intended for shoot growth. Common during summer in gardens and parks.

Cotton Harlequin Bug adult from above. Photo: Mark Crocker

This photo shows the Tectocoris diophthalmus Cotton Harlequin Bug female guarding eggs. Photo: Robert Whyte

This photo shows the Tectocoris diophthalmus Cotton Harlequin Bug clustering nymphs. Clustering behaviour is an advantage to survival. The individual bugs have bad smelling scent glands and when it is emitted in one it triggers others in the group, multiplying the bad smell. Predators avoid bad-smelling, bad-tasting prey until they themselves evolve to deal with the smell, the taste and the toxins. Photo: Robert Whyte

This photo shows the spent egg cases of Tectocoris diophthalmus Cotton Harlequin Bug. Photo: Robert Whyte 

Metallic Shield Bug

Metallic shield bug Scutiphora pedicellata is commonly found sheltering in groups of 10–20 in leaf litter or under bark, particularly around the bases of native trees. It feeds on vegetative growth, as well as on fruits.

Photo: Robert Whyte

Parent Bug

Parent Bug Cantao parentum is a 20-mm-long jewel bug, orange with black splotches. This one is on its food plant, Mallotus claoxyloides Smell of the Bush resting on the ripe fruit. Parent Bugs also feed on the closely related Red Kamala Mallotus philippensis.

Photo: Robert Whyte

This photo shows a Parent Bug Cantao parentum adult guarding eggs. Photo: Robert Whyte

This photo shows a Parent Bug Cantao parentum adult guarding young. The Parent Bug is so named because adults remain with their offspring for several weeks after they hatch to protect them from predators. This is “relatively” rare behaviour in the insect world. The young in this image are about five days old. Photo: Derek Boddington

These Parent Bug nymphs are well developed – it won’t be too long before they develop into adults. They react to disturbance reluctantly, eventually seeking refuge along the stems of the plant if contually disturbed, but return to clustering on leaves if they are left alone. Photo: Robert Whyte

Green Jewel Bug

Lampromicra senator or Green Jewel Bug is a bug whose food plant is Breynia oblongifolia Coffee Bush, a common plant in the Enoggera area. This photo shows a Green Jewel Bug sheltering on the undersides of a leaf of its food plant. Adults are capable of flying, which this one did. These sap-sucking bugs form non-feeding clusters during hot dry periods, spreading out to feed again when conditions improve. In dry times they also congregate along creeks where the feeding is better.

Photo: Robert Whyte