Order: Verrucariales       Family: Verrucariaceae Species: Dermatocarpon leptophyllodes Growth type squamulose to foliose. On lakeside rocks. Gougane Barra and Inchigeela, Cork, SW Ireland. Very small and tightly crowded, greyish-brown thallii 2-7mm, each with a central holdfast. The lobes are sometimes pruinose. Immersed perithecia with clearly visible ostioles. Can form large, dense colonies that sometimes resemble a cracked areolate crust. The asci are 8-spored, spores simple, (12-)15-22 x 5-7.5(-8) µm. Micrograph below. Occurs on flat-topped siliceous rocks in and beside streams, rivers and upland loughs. Mainly SW Ireland. Chemical reactions negative. Similar: Dermatocarpon meiophyllizum

Micrograph

Dermatocarpon leptophyllodes. August and October 2009