Helopeltis

General information

Helopeltis sp. are also known as tea mosquito or mirid bugs.

Scientific name

Helopeltis sp

Description of adult

Adults are 6.5-8.5 mm long, dark brown to reddish brown but with an orange thorax. There is a dark pin-like protrusion from the centre of the thorax. The legs are long and fragile, resembling those of a mosquito.

Immature stages

The eggs are white and elongated and about one millimetre long. Later instar nymphs are similar in appearance to the adults, although wingless and orange-brown in colour. Legs are spindly and black.

Life history

The eggs are laid in plant tissue singly or in small groups. The stems and petioles of young leaves are the main oviposition sites. Eggs take about a week to hatch. Nymphs feed on young leaves and shoots, or other developing plant parts. There are five nymphal instars, with a total development period of 10-16 days. Adults can live for several weeks, and females may lay 30-50 eggs during this time.

Distribution

Northern Queensland, but the distribution is poorly known.

Host range

Cocoa, tea, cashew, avocado, mango, guava, passionfruit and sweetpotato.

Damage

Helopeltis are a serious and spasmodic pest of cashews. Their sucking activities result in young leaves of cashews becoming distorted with lesions along the main veins. Bunched terminal growth develops after severe attack. Developing apples and nuts can show brown sunken spots. Damage is easily confused with that of the fruit-spotting bugs.

Control options

Examine five trees at six widely spaced locations throughout the crop. Spray when damage is first noticed on developing fruit.

Biological

Green tree ants, once established in an orchard and correctly managed, can suppress Helopeltis damage. Take care with green tree ants as they can also become a pest, especially in wet environments. The ants have symbiotic relationships with sap sucking honeydew-producing insects such as mealy bug and scale. Green tree ants may also cause problems due to aggressive behaviour toward beneficial insects and fruit pickers at harvest.

Chemical

Prompt spray application is required to prevent serious damage.

Chemical registrations and permits

Check the Australian Pesticides & Veterinary Medicines Authority chemical database and permit database for chemicals registered or approved under permit to treat this pest on the target crop in your State/location. Always read the label. Always observe withholding periods.

Last updated 03 September 2012