A small landscape on stone
A lichen’s raised structures bring relief to the rock.
Includes an activity to try →Explore: Still in the small world →Read here and view sources
In Pedro Andrade’s photograph from 31 January 2025, a brownish-grey lichen has rounded bumps on a rock. The record is identified as Lasallia pustulata and located in Abadim by checking its public point against CAOP2025.
The University of Évora describes this species as saxicolous, meaning it lives on rock. Its thallus is umbilicate: it attaches to the surface only at its centre. The raised bumps on the upper face are another detail described by the source.
The photograph shows the relief but not the attachment point hidden underneath. Comparing what is visible with what the description explains is a way to learn without lifting or detaching the lichen.
Évora’s profile describes a single lobe that can reach ten centimetres, with small branched structures called isidia along its edges. The surface may have a whitish coating called pruina. Outline, edge and relief are three different observations; no measurement should be estimated from the photograph without a known scale.
Source and context
University of Évora — Biodiversity of Mitra, Lasallia pustulata
Accessed: . Editorial summary; the date of consultation is not the date of the facts.