- Widespread distribution. A pest of food and field legumes, especially cowpeas, and other Vigna species. Minor pest.
- Adults and nymphs suck pods causing pitting and shrivelling of seeds. Also, damage flowers and buds.
- Adults are 10-12 mm long, dull brown, narrow, almost parallel-sided, with cream stripe along the side, and prominent eyes. Nymphs are ant-like.
- Cultural control: plant far from already infested crops; handpick bugs where plots are small; destroy remains of plants after harvest.
- Chemical control: PDPs, e.g., derris, pyrethrum or chilli. If commercial products needed, use synthetic pyrethroids or malathion. Use products recommended against green vegetable bug (see Fact Sheet no. 98).
Pacific Pests, Pathogens, Weeds & Pesticides
Bean bug (349)
Photo 1. Adult bean bug, Melanacanthus margineguttatus, showing the large eyes, spines on the leg, and cream stripe down the sides.
Photo 2. Adult small brown bean bug, Melanacanthus scutellaris, showing cream stripe alongside the body.
Melanacanthus margineguttatus; the brown bean bug (or small brown bean bug), Melanacanthus scutellaris, is similar. It also attacks pulses. (Note, there is little information on Melanacanthus margineguttatus in the literature, mostly reports are on Melanacanthus scutellaris - a species native to Australia.)
AUTHOR Grahame Jackson
1Information from Swaine G (1971) Agricultural Zoology in Fiji. Her Majesty's Stationery Office. London; and DAF (2020) Brown bean bug. Business Queensland. Queensland Government. (https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/crop-growing/pests-field-crops/brown-bean-bug); and from McCaffrey S (2011) (Melanacanthus nr. scutellaris ): PaDIL - http://www.padil.gov.au. Photo 1. Coreoidea species file online. Melanacanthus margineguttatus Distant. The Leverhulme Trust. (http://coreoidea.speciesfile.org/Common/basic/Taxa.aspx?TaxonNameID=1186292). Photos 2&3 The Beatsheet. Insect Pest Management for Australia's Northern Region. (http://thebeatsheet.com.au/resources/insect-identification/podsucking-bugs/bbsm/). Photo 3 Melanacanthus scutellaris (14528939742).jpg Wikimedia Common.(https://commons.wikimedia.org/wiki/File:Melanacanthus_scutellaris_(14528939742).jpg).
Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.