Blethisa multipunctata (Linnaeus, 1758)

Description: Large (10-14mm) bronze ground beetle with greenish margins to the elytra and pronotum. Elytra have prominent depressions and punctures like Pelophila but this is a larger species with differently shaped pronotum and green reflections. Widespread in seasonally flooded marshes, riverbanks and lakeshores with luxuriant vegetation.

NI account: Widely distributed but local, though much less rare than in Britain.

Ecology: A stenotopic species of muddy or silty river and lake margins which are subject to periodic inundation. It is also widespread but uncommon in the inter-drumlin fens of Down and Armagh (B. Nelson, pers. comm.). One of the first carabids to appear in spring, patrolling the flooded fringes of water bodies. It appears at home in the water itself, having been observed swimming freely when pursued and diving to scuttle rapidly along the bottom looking for concealment (R. Anderson). The preference for water-bodies with variable water-tables is well illustrated by a large colony found on the fluctuating, bare-peat shorelines of the Spelga Reservoir in the Mourne Mountains, Down. This unstable artificial habitat is of relatively recent origin but seems to be preferred to natural, gravelly or peaty shorelines of upland lakes nearby which are untenanted.

Distribution: A circumpolar Wide-Boreal species (36), found across northern and central Europe to Siberia and northern North America.

Similar Species: Pelophila borealis: With punctate foveae but with ten striae; pronotum cordate; upper surface bronze

Key Identification Features:

  • Elytra with punctate foveae on 4th and 6th striae (cf. Fig. 4)
  • Nine elytral striae
  • Frontal furrows unique (Fig. 19)
  • Upper surface bronze but with greenish edges to the elytra and pronotum

Distribution Map from NBN: Blethisa multipunctata at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Blethisa multipunctata at iNaturalist World Species Observations database.

GBIF data for Blethisa multipunctata | Classification: Insecta, Coleoptera, Carabidae, Blethisa

Thumbnails for genus Blethisa

 Anderson, R., 2025. Blethisa multipunctata. (Linnaeus, 1758). [In] Ground Beetles of Ireland.
https://www2.habitas.org.uk/beetles/species.php?item=7166. Accessed on 2025-04-03.