Description: A glossy dark animal and shell of 4½ moderately convex whorls. The shell has fairly deep sutures and a moderately raised spire. Surface with irregular coarse growth lines. Umbilicus wide. Recognisable in the field by being very dark, nearly black, the dark animal showing through the translucent brown shell. Common on river and lake margins. 6-7 mm.

World Distribution: Widely distributed in Europe and across Siberia to the Pacific. Also in northern North America. Distibution type: Circumpolar Temperate (76).

Irish Distribution: Found across central and southern Ireland and north to Lough Neagh, but scarce in western and northern districts of Ireland.

Ecology:

• Common on richer, 'fenny' lake and river margins, typically where Mentha spp. grow
• Rarely found in areas subject to large fluctuations in water level or in wetlands such as turloughs liable to dry out in the summer
• Very hygrophilous and amphibious

Key Identification Features:

• A very dark animal and shell
• Shell surface glossy and a translucent deep brown but often obscured by adhering algae or mud
• Whorls moderately convex with deep sutures
• Spire a little more convex but with fewer whorls than Z. excavatus (4½ vs 5½)

Red list status:

• Least concern (lc).

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

iNaturalist: Zonitoides nitidus at iNaturalist World Species Observations database.

GBIF data for Zonitoides nitidus | Classification: Gastropoda, Stylommatophora, Gastrodontidae, Zonitoides

Thumbnails for genus Zonitoides