Invertebrate Tectocoris diophthalmus (Cotton Harlequin Bug)


John McDouall Stuart
Jul 2, 2011
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Wide Bay, QLD
Scientific Name: Tectocoris diophthalmus

Common Name(s): Cotton harlequin bug

Other Names:
Jewel Bug

Class: Insecta

Order: Coleoptera

Family: Scutelleridae

Genus: Tectocoris

Species: T. diophthalmus

Distribution: Eastern Australia

Habitat: Urban, agricultural and coastal areas.

Field Notes: Brightly patterned in yellow, orange, red, metallic green or metallic blue colours. Usually females are orange and males blue-red. Feeds on many species belonging to the hibiscus plant family (Malvaceae) and cotton by sucking out sugary juices of young stem shoots. Considered minor pest status with cotton. Eggs are laid in a cluster encircling a branch guarded by an adult.
Size - 20 mm.

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Above photo of Nymph. These are mainly metallic blue or metallic green. Although this one was found by itself they are noted to be in groups when feeding on cotton bolls.

Australian Museum
Queensland Government Dept Agriculture, Fisheries and Forestry
Zborowski, P. (2010). A field guide to insects in Australia. 3rd edition