MolluscIreland - land and freshwater
  • Balea (Balea) sarsii Pfeiffer 1847 Tree snail
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Balea (Balea) sarsii
© Dr Roy Anderson

Map hosted by the National Biodiversity Data Centre, Waterford
To view the species profile on Biodiversity Maps and access the live map, please click on the map.


A small, fairly glossy shell which is narrowly but evenly conical. Aperture oval, lacking teeth or lamellae. Outer lip simple. Surface relatively smooth but crossed by coarse radial growth lines. Colour varies from a translucent mid brown to yellowish or greenish-brown. Mainly on trees but also walls.

Key characteristics

  • A medium-spired narrowly conical shell
  • Surface glossy but crossed with coarse radial growth lines
  • Colour mid to dark brown or with a strong greenish or yellowish cast
  • Aperture a rounded oval without teeth or lamellae
  • Lip simple, not re-inforced


6-8 mm.

World Distribution

Uncertain at present but probably confined to the extreme western seaboard of Europe and the Atlantic isles. Distribution type: Oceanic Temperate (71).

GBIF distribution map [open in new tab]

Irish Distribution

Distributed across Ireland in suitable habitats and common or abundant in wooded areas.


  • Primarily a tree species found under bark of both living and dead broadleaf species
  • Also on Sitka spruce and other conifers in high rainfall areas, feeding on epiphytic lichens
  • On the coast found on rocks above high water mark feeding on lichens, mainly species of Xanthoria alkaloids from which it retains parietin as an antifeedant to fend off predators (Baur et al. 1998)


The name heydenii has now been superceded as the species was described from Norway at an earlier date than von Maltzan, under the name sarsii Pfeiffer.

Red List status

  • Least concern (lc

Wikipedia link

Wikipedia page for Balea sarsii

 Anderson, R., (2016). Balea (Balea) sarsii Pfeiffer 1847. [In] MolluscIreland. Accessed on 2024-03-02.