Carabus auratus

Distinguished from similar ground beetles by the combination of iridescent gold-green coloration on elytra, head, and thorax, paired with orange appendages. The three broad longitudinal grooves on each elytron are diagnostic. Flightless condition and diurnal activity pattern further separate it from many nocturnal Carabus species. Size range of 17–20 mm helps distinguish it from smaller congeners.

Adults measure 17–20 mm in body length. The elytra display an iridescent gold-green coloration, each marked with three broad longitudinal grooves. The head and thorax share this gold-green iridescence. Legs, antennae, and mouthparts are orange. The species is flightless.

Occurs in fields and shrubby areas, particularly on loamy soils. Occasionally climbs into trees. Requires shelter such as stones or moss for overwintering.

Native to central and western Europe including Great Britain, Denmark, Sweden, France, Belgium, Netherlands, Germany, Switzerland, Austria, Czechia, Poland, and Spain. Introduced to North America (USA).

Adults active during daytime throughout the growing season. Larvae hunt at dawn. Adults emerge from pupation in autumn and overwinter. Life expectancy approximately two years.

Predatory. Adults feed on insects, snails, and worms, seizing prey with mandibles and spraying with digestive secretion prior to consumption. Documented to prey on agricultural pests including the Colorado potato beetle (Leptinotarsa decemlineata).

• Leptinotarsa decemlineata - preyColorado potato beetle, agricultural pest

Complete metamorphosis. Larvae hunt exclusively at dawn, undergo three molts, then pupate in soil. Adults emerge in autumn. Overwintering occurs under stones or moss. Life span approximately two years.

Diurnal predator. Adults actively hunt during daylight hours. Larvae exhibit crepuscular hunting behavior restricted to dawn. Adults occasionally climb vegetation. Overwinters in sheltered microhabitats.

Generalist predator in terrestrial ecosystems. Functions as biological control agent in agricultural and garden habitats through predation on herbivorous pests.

Considered beneficial to farmers and gardeners due to predation on crop pests, particularly the Colorado potato beetle. No documented negative impacts.

• Carabus nemoralisSimilar size and habitat preference; distinguished by coloration (C. nemoralis typically bronze or coppery without gold-green iridescence) and elytral sculpture
• Other Carabus speciesMany congeners share ground beetle morphology; C. auratus distinguished by unique gold-green iridescence combined with orange appendages and three longitudinal elytral grooves

• predator
• diurnal
• flightless
• beneficial insect
• biological control
• introduced species

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
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