ASCOMYCOTA | LECANOROMYCETES > LECANORALES > Cladoniaceae

Common name:            Buck's-horn Cup Lichen (not in frequent use)           

Synonyms:                    -

Habitat:                          Heathland, coastal dunes

Substrata:                      Basic to mildly acidic soils

Growth forms:              Terricolous               

Basal thallus:                  Squamulose

Secondary thallus:        Podetia, regular shallow cups

Apothecia:                    Lecideine, rare, pale brown fruits

BLS identity rating:        Graded 2/5 (visual identification relatively easy with care)

Basal squamules often dominant and usually well-developed, up to 5mm long, more or less rounded with notched margins, upturned when dry; mostly contiguous and forming cushions; greyish-green to grey-brown with white, but often tinged undersides.

Podetia short-stalked with shallow cups, proliferating irregularly, usually from the centre and sometimes forming tiers; apothecia rare but, where present, brown on scyphus margins; pycnidia frequent.

Cladonia cervicornis was previously split into three subspecies; the described form ssp.cervicornis; a generally darker form ssp.verticillata, with smaller squamules and up to seven layers of proliferation; and a much rarer, more elaborately tiered, albeit more often sterile, slender form ssp.pulvinata.

Those subspecies are now generally considered as separate species in their own right so, the differentiation now is primarily between Cladonia cervicornis and Cladonia verticillata. Hopefully, I'll have a separate page for Cladonia verticillata at some point, but until I've found that species it makes sense to describe the main differences here. Previous descriptions used to suggest that the tired form was ssp.verticillata, but Cladonia cervicornis also has scyphi that may proliferate and, although they would rarely exceed two or three tiers, it's not a good indicator in itself. In Cladonia verticillata the podetia tend to have more regular, neater scyphi, but the only reliable visual feature is that Cladonia cervicornis has larger, more elongate, indented basal squamules, whereas in Cladonia verticillata the squamules are rounded and much smaller or, in fact, pretty much evanescent especially in mature specimens.

Both species have widespread, albeit local distribution; rare in many areas, but can be common in certain habitats. In the New Forest, Cladonia cervicornis is most frequently found in grasslands or along disturbed path edges across the heaths, whereas Cladonia verticillata is more likely to occur on low productivity soils on taller, ungrazed heathland.

Note: unfortunately, all of the previously featured photos for this species have been deleted due to misidentification; the thumbnail is also incorrect, but has been temporarily retained as a link to the 'species account'.