COLEOPTERA > POLYPHAGA > CHRYSOMELOIDEA > Chrysomelidae > Bruchinae

This group includes nine native species and six accidentally introduced, and now established, pest species of stored pulses. They were originally treated as a separate family and, because of their short broad rostrum and general appearance, were regarded as close relatives of weevils. Some species are known as pea weevils or bean weevils, but the common name of seed beetles is a better collective term.

Species range from 2-5mm long, are compact and oval with distinct side margins to the elytra, and are typically shades of brown and/or black in colour. The elytra is usually pubescent and truncate revealing the pygidium. The eyes are obviously notched, which distinguishes them from other Chrysomelidae subfamilies. The antennae are eleven segmented and relatively short, normally serrate or pectinate, rarely filiform.

The adults are pollen-feeders found on a variety of mainly white or yellow flowers. They typically become active from late April or May with the females ovipositing into ripening seed pods of Fabacaea (legume, pea or bean family) where the larvae will develop and feed. Some species may cause infestations within harvested crops.

Bruchus rufimanus, commonly known as the Bean Seed Beetle or Broad-bean Weevil, is one of the larger species. Their main host plant is broad-bean, but peas, sweet peas and lupins may also be used. The species is reasonably distinctive with its short and broad rostrum, and very deeply notched eyes that are almost crescent-shaped and strongly protruding behind the antennal insertions. The first four segments of the antennae are usually a pale orange colour. The elytra is broadly oval and distinctly wider than the pronotum, each with ten well impressed striae, which end before the apex. The intervening spaces between the 'grooves' are flat and variously scaled, usually with a mix of dark brown/grey and cream and with paler patches that form two transverse bands. Individuals obviously become worn so the markings become less defined with age.

Created, Jan.22 (v.1)