Ground Beetles of Ireland

Agonum thoreyi

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Agonum thoreyi
© Roy Anderson
Agonum thoreyi
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(Maps updated 30th November 2009)

Agonum thoreyi Dejean, 1828

Description: A small (6-8mm), black ground beetle which is widespread and common in damp, heavily vegetated water margins, especially in beds of common reed, Phragmites, or reedmace, Typha. Two colour forms occur, the uniformly dark puellum and thoreyi, with paler, brownish, elytra, pale limbs and pale first antennal segment.

World Distribution: A Eurasian Wide-temperate species (65) found across Europe except the south, and eastwards into Siberia as far as the River Amur. Introduced in North America.

Irish Status: Like the previous species prefers well-vegetated water margin biotopes but more associated with lakeshores than with fens. Nearly always gregarious and common where it occurs.

Ecology: Recorded from a wide range of vegetated, eutrophic lakeshores and riverbanks; also swamps and fens. Not recorded from ombrotrophic mires. Often found hibernating in hollow Phragmites stems on lakeshores.