Rhizocarpon torquatum

Species of lichen

Rhizocarpon torquatum is a species of saxicolous (rock-dwelling), crustose lichen in the family Rhizocarpaceae. This species is recognised by its pale, thick, smooth, areolate thallus that contains hypostictic acid as a major metabolite, and its large apothecia that are distinctively adorned with a whitish inner collar in immature stages.

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