Description: Recorded only from County Fermanagh, L. atomaria is a ‘bark-pimple’ species of aspen Populus tremula. The spores of this genus can be distinguished by their elongated and curved spindle-like shape. The spherical discs or perithecia have a hard outer shell (involucrellum). L. atomaria has a whitish thallus with perfectly circular discs surrounded by a fringe; the spores can be one- to three-septate.

Key Identification Features:

• Thallus white to grey on aspen bark with ‘bark-pimple’ discs
• Discs circular (tiny dots) with a neat and conspicuous halo-like fringe; spores one- to three-septate.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Leptorhaphis atomaria at iNaturalist World Species Observations database.