Yellow spotted stink bug - Erthesina fullo (Thunberg, 1783)

(NOT present in New Zealand)

ADULT: Main diagnostic characters

[Erthesina fullo]. SIZE: 18-23 mm. COLOUR: Blackish with yellow spots and middle line on head and front of body, and yellow-banded legs. ABDOMEN: Sides with alternate black and yellow markings. © MWLR | CC BY-NC 4.0 Image — Erthesina fullo. SIZE: 18-23 mm. COLOUR: Blackish with yellow spots and middle line on head and front of body, and yellow-banded legs. ABDOMEN: Sides with alternate black and yellow markings. © MWLR | CC BY-NC 4.0

[Erthesina fullo]. ANTENNA with narrow pale band at base of segment 5 only. HEAD AND FRONT BODY with yellow middle line. © MWLR | CC BY-NC 4.0 Image — Erthesina fullo. ANTENNA with narrow pale band at base of segment 5 only. HEAD AND FRONT BODY with yellow middle line. © MWLR | CC BY-NC 4.0

[Erthesina fullo] ventral view. BEAK (tube-like mouthparts between legs) long, extending well beyond hind legs. ABDOMEN COLOUR (behind legs): Yellowish brown with several large dark markings, especially along sides. © MWLR | CC BY-NC 4.0 Image — Erthesina fullo ventral view. BEAK (tube-like mouthparts between legs) long, extending well beyond hind legs. ABDOMEN COLOUR (behind legs): Yellowish brown with several large dark markings, especially along sides. © MWLR | CC BY-NC 4.0

NYMPH: Main diagnostic characters

Immature stink bugs or nymphs moult through five stages (instars) before becoming adults; the fifth stage or last instar nymph is shown below.

[Erthesina fullo] last instar nymph. © Derivative of photo by 'itchydogimages on Flickr', used with permission (available under CC BY-NC 4.0 license) Image — Erthesina fullo last instar nymph. © Derivative of photo by 'itchydogimages on Flickr', used with permission (available under CC BY-NC 4.0 license)

BODY LENGTH: About 16 mm. COLOUR: Brownish grey outlined with yellow, with scattered red spots; head, thorax with yellow mid line; abdomen with large dark plate; legs dark, hairy; antennae with narrow pale band at base of segment 5 only. THORAX: Sides without spines. SHAPE: Pear-like.

Distribution and pest status

The Yellow Spotted Stink Bug (YSSB; Erthesina fullo) is native to Asia, including China, Japan, Vietnam, and Taiwan. MPI intercepts live and dead specimens of this insect periodically. To date, no breeding population has established in New Zealand.

There is limited information on host range or impacts on plants and trees although impacts on timber trees and horticultural crops have been noted. For example, YSSB has been recorded to cause damage to Paulownia trees, poplars, ya or Chinese white pear, peaches and nectarines, apple, pine trees, some hardwood trees, Chinese cinnamon.

YSSB spends winter in the adult stage, sometimes under bark or in natural crevices, and becomes active again during the warm sunny days of spring when adults mate and females lay their eggs on leaves. The nymphs go through five stages of development during the summer before becoming adults. YSSB adults and nymphs feed by inserting their long, tube-like sucking mouthparts (rostrum or beak) into the fruits, leaves and stems of a variety of plants from which they suck fluids containing sugars and nutrients.

Photos of eggs and nymphs can be found on Flickr.

YSSB is not a risk to human health. When disturbed or crushed, it can emit a characteristic, unpleasant and long-lasting odour that is not health threatening.

(See also linked resources below.)

Pathways for incursion into New Zealand

YSSB is a known hitchhiker pest which can arrive in New Zealand in a variety of ways, e.g., passengers/luggage, containers, general cargo or used machinery and vehicles. This makes it difficult to identify and manage specific entry pathways.

MPI has a number of measures in place to reduce the risk of exotic pests being introduced including requirements for importers and screening at the border. However there is no such thing as zero risk and it is possible the insect could hitchhike its way into the country undetected.

(See also linked resources below.)

What people can do

Keep an eye out for this bug. Report findings of any suspects to MPI on 0800 80 99 66. If possible take a photograph and/or collect samples.