Lecidella elaeochroma

Lecidella eleaochroma

January is generally a quiet month for British gardens, but there are still plenty of things out there to discover. This is Lecidella eleaochroma, one of our more common lichens. Scores of them stud the trunks of many of our smooth-barked trees, often butting up against nearby colonies of Lecanora chlarotera. Where they do, a black prothallus develops along this lichen's leading edge. Like other members of the genus Lecidella, these are crustose, which means they adhere closely to the substrate upon which they grow. You couldn't get a fingernail under one; to remove it, you'd have to strip the tree's bark right off. Colonies tend to be greyer in shady spots and yellower in sunny areas, and are liberally sprinkled with round black apothecia, the fruiting bodies that contain the lichen's fungal spores. Unlike some of the other lichens I've profiled on the blog so far, this one reproduces primarily by spores, which contain only the lichen's fungal partner. This means a germinating spore must quickly find (or steal!) an algal partner – a far trickier proposition than bundling both components together in a soredium, like some lichens do. Lecidella eleaochroma is widespread across the British Isles, and indeed across all of Europe and much of North America as well.