Jelly lichen Leptogium gelatinosum
Compact cushions of this tiny lichen were noted on 20th December amongst mosses in sandy soil on the top of a roadside wall at Clashnessie (NC0530). The cup-shaped apothecia are just over 1mm in diameter and arise from a dark greeny-brown, wrinkled, papery thallus with frilly edges. This species likes calcareous substrates (probably shell sand in this case) and has been recorded elsewhere in Assynt, especially on the limestone.
The photosynthetic partner of jelly lichens is the cyanobacterium Nostoc, which sometimes forms extensive, brown, lettuce-like (and slippery) colonies locally on little-used, gravelly surfaces. A nice find in a brief gap between showers of sleet and hail.