LICHALP

Thelidium arnoldii Zschacke

Syn.: Thelidium bubulcae sensu Arnold non A. Massal.

Lichenised. Poorly known taxon.

Substrate: calciferous rocks

Altitudinal range: from the montane belt (potential vegetation: deciduous forests dominated by Fagus sylvatica and closed coniferous forests with Picea abies) to the alpine belt (potential vegetation: treeless Alpine grasslands and tundras, to the lower limit of perennial snow and the equilibrium line of glaciers)

Note: a species of the Th. incavatum-group with somewhat wider, ellipsoid, 1- to 3-septate ascospores; on limestone, most common at low elevations; the available distributional data are difficult to interpret, because this taxon was not generally accepted.