Coreus marginatus

Coreus marginatus is a herbivorous species of True Bug in the family Coreidae. It is commonly known as the dock bug as it feeds on the leaves and seeds of docks and sorrels. It is a medium-sized speckled brown insect, between 13 and 15 mm long as an adult, with a broad abdomen. It occurs throughout Europe, Asia and northern Africa. It is often found in dense vegetation, such as hedgerows and wasteland. This species was among the first Hemiptera formally described in the scientific literature by the Swedish biologist Carl Linnaeus in 1758, under the name Cimex marginatus. It was transferred to the genus Coreus by the Danish zoologist Johan Fabricius in 1794. It has numerous synonyms and was historically placed in the genus Syromastus. The specific epithet marginatus refers to the prominent margins of the abdomen. The head, pronotum and abdomen of an adult dock bug are speckled reddish brown. The antennae are composed of four segments, red-orange in colour except for the final fourth segment which is black. Between the antennae are two small projections, known as antenniferous tubercles, which can be used to distinguish this species from other superficially similar species. The pronotum has angular upward facing projections and the scutellum is clearly visible. The rounded edge of the abdomen has lighter coloured markings. Adults are between 13 and 15 mm long and males are typically smaller than females but have longer antennae.