The seed pods are long and flattened. The round structures are galls which have been formed by an insect.
This is the developing wasp larvae inside a gall. In response to a wasp laying its egg inside the plant's tissue, the plant forms a gall and seals off the damaged area. The egg then develops inside the gall, feeding on the plant tissue, and emerges later as an adult.
Bossiaea eriocarpa
Common name: Common Brown Pea
Bossiaea is named in honour of Joseph de Bossieu de la Martiniere (1754 – 1788), medical officer and botanist on Astrolabe, La Perouse’s voyage 1785 – 1788. Eriocarpa is from the Greek words erion, meaning wool, and carpos, meaning fruit.
Occurs in the southwest of Western Australia.
A shrub to 60 centimetres tall. The yellow and brown flowers are produced from July to October.
A species of wasp, Tanaostigmodes sp, lays its eggs in the tissue of Bossiaea eriocarpa. In response, the plant forms a gall around the foreign body – the egg. The young wasp feeds on the plant tissue inside the gall. It pupates in the gall and emerges as a fully formed adult wasp.
Tanaostigmodes sp.
Western Australian Plant Names and their Meanings, a Glossary. FA Sharr. 1996.
Flora of the Perth Region. NG Marchant, JR Wheeler, BL Rye, EM Bennett, NS Lander, TD Macfarlane. 1987.
Atlas of Living Australia https://bie.ala.org.au/species/https://id.biodiversity.org.au/node/apni/2915386
Florabase https://florabase.dbca.wa.gov.au/browse/profile/3710