Peltigera canina
A large Dogtooth lichen found in dry grasslands, characteristic of dry coastal grassland, but also widespread in suitable habitat inland as well. Part of the Peltigera membranacea group with wide lobes and a thickly white-grey tomentose upper surface. The fluffy rhizines distinguish it from Peltigera membranacea, which is found in damper habitats.
Like Peltigera membranacea, but, less strongly bullate-ridged, with more flattened, smooth veins in the central parts of the thallus and irregular rhizines that are markedly bushy and beard-like, and confluent at the base. Apothecia dark brown to black, saddle-shaped. Ascospores 42–53 × 2.6–5.2 µm. Thallus with negative reactions; no lichen products detected by TLC.
The bullate lobes with inflexed margins and richly branched woolly confluent rhizines are diagnostic.
Amongst moss and short grass, on arid sandy slightly basic to acid soils and dunes, fixed shingle, heathland and dry grassland. Usually in drier habitats than the similar Peltigera membranacea.
Widely dispersed but local in Britain and Ireland. Many old Irish records may actually be for Peltigera membranacea.
Cannon, P., Magain, N., Sérusiaux, E., Yahr, R., Coppins, B., Sanderson, N. & Simkin, J. (2021). Peltigerales: Peltigeraceae, including the genera Crocodia, Lobaria, Lobarina, Nephroma, Peltigera, Pseudocyphellaria, Ricasolia, Solorina and Sticta. Revisions of British and Irish Lichens 20: 1-34.
Text by Neil A Sanderson based on Cannon et al (2021)