Cladonia cyathomorpha in the New Forest

(BLS data from the NBN)

Andy Cross and I had an afternoon walk in the New Forest on Saturday 11th January 2014, with the aim of starting to record an isolated heathland square north of Berry Wood (SU2106). This involved walking through rich ancient Beech - Pedunclate Oak - Holly pasture woodland before reaching the heath. After doing 1km without looking at a lichen to get to the wood, we checked the best looking trees as we went through.

One good target I spotted was a long fallen big Beech trunk that was in a nice state of decay. This habitat supports a good mix of Cladonia species, which is usually more diverse than the assemblage on Oak trunks. This produced exactly what I was looking for; a massive colony of Cladonia cyathomorpha.

Cladonia cyathomorpha site

This had nice big basal squamules, with clear white veining on the undersides, which became orange-brown and even very slightly pinkish at the base of the largest squamules. Most of the podetia were typical with simple cups, with smooth podetia stalks below and corticate granules above, especially inside the cups. Some our material, however, had quite odd baroque poliferations. These were twisted and bifurcated with brown apothecia/pycnidia (these looked like sterile apothecia internally) on the tips. The poliferations do not seem to have been described before and apothecia are described as very rare in the LGBI.

Cladonia cyathomorpha specimen

So I am now happy that Cladonia cyathomorpha is in the New Forest; the first modern records for the lowlands. Cladonia pyxidata appears more frequent on the trees; it has mealy unviened undersides and squamules on the podetia as well as the cups. Cladonia cyathomorpha is probably widespread in the Forest in sheltered humid locations, and must occur elsewhere in the lowlands. There is an old record from the Surrey Weald in the BLS mapping database but with no data attached. It is likely to be a species of old or little disturbed habitats in the lowlands.

Andy was curious what the name meant, so looked it up and it is a compound of cyath - cup and morph – shape. So, a crude translation of its scientific name is the Cup-shaped Cladonia though an actual translation by someone who knew tenses etc would give a more accurate name. Out of all the Cladonia species with cups, why chose this species to carry the name?

I tracked down the original publication: Watson, 1935, J. Bot. 73, 156, link to PDF. It seems the name actually refers to the curled up cup like dry basal squamules, not the the cups on the podetia, so not quite so odd, but still a bit of a herbarium based name, as the lichen is probably rarely that dry in its typical habitats.