Necrodes littoralis is a large (15-25 mm) black carrion beetle with ridged elytra and black antennae, the outer three segments of which are orange.
Immature specimens are brown.
In the male, the thighs of the hind legs are clearly thickened.
Necrodes littoralis is sometimes confused with the Black Sexton Beetle (Nicrophorus humator) but that one has clear buds at the end of its antennae and elytra with only faint ridges.

Caught in my self made moth trap.

In my yard, Hilversum, The Netherlands, 9 September 2023