Glossy Marsh Ground Beetle
Agonum micans
The Glossy Marsh Ground Beetle (Agonum micans) is a small carabid beetle characterized by its metallic luster and its preference for extremely moist habitats such as shorelines and bogs. It belongs to the genus Agonum, which includes many specialized marsh dwellers. In Central Europe, the species is widespread but reacts sensitively to the drainage of its habitats. As a predatory inhabitant of the leaf litter, it plays an important role in the local food web.
Details
Identification
Upper side with metallic bronze, greenish, or blackish luster; pronotum heart-shaped and narrower than the elytra; elytra with fine striae.
Social behavior
Solitary, but often occurs in high individual densities at optimal sites.
Diet
Predatory lifestyle; feeds on small invertebrates such as insect larvae, mites, and worms.
Hunting strategy
Active searching for prey in the leaf litter and low vegetation.
Spawning substrate
Moist substrate, often moss or detritus near water.
Overwintering
Overwinters as an adult in leaf litter or under bark in drier peripheral areas.
Ecology
Ecological role
Important predator in aquatic-terrestrial transition zones; regulates small insect populations.
Natural predators
Insectivorous birds, amphibians, and larger predatory arthropods.
Competitor species
Other hygrophilous ground beetle species of the genera Bembidion or Pterostichus.
Ecosystem service
Natural pest regulation and contribution to functional diversity in wetlands.
Threats
Habitat loss due to drainage, damming of rivers, and the destruction of fens.
Scientific profile
Profile
Distinguishing features
The most important feature of the subgenus Europhilus is the third antennal segment, which is pubescent in its apical half. The pronotum is significantly narrowed towards the base with rounded posterior angles. The mentum has a tooth. The elytral striae are finely punctured, and the apical margin of the elytra is evenly rounded near the shoulders.
Habitat
Stenotopic hygrophilous species. Inhabits muddy riparian zones of standing and slow-moving waters, sedge marshes, reed beds, wet meadows, and alder carr forests. Prefers sites with high organic matter and dense vegetation.