ASCOMYCOTA | LECANOROMYCETES > LECANORALES > Cladoniaceae

Common name:             None in regular use

Synonyms:                     -

Habitat:                           Heathland, bogs

Substrata:                       Acid peat and sandy soils, rotting stumps

Growth forms:               Terricolous, lignicolous                               

Basal thallus:                  Squamulose  

Secondary thallus:         Podetia, 'goblet-shaped' cups

Apothecia:                     Lecideine, rare, brown fruits

BLS identity rating:        Graded 4/5 (see note - can only be confirmed with TLC)

Basal squamules small, slightly incised, rather inconspicuous and soon disappearing.

Podetia typically up to 20mm or possibly 30mm tall; expanding smoothly to the cups (scyphi), which are generally around 3- 7mm dia., usually regular and rarely proliferating from the margins; the surface is sorediate, but becomes easily eroded leaving any remaining soredia mixed with microsquamules.

Colour pale grey to grey-greenish with a distinct brown tinge, sometimes blackened at the base; exposed medulla pinkish- brown; the scyphi have a variable purplish-coloured rim that may extend to cover the inside of the cup and/or the outer surface.

From that description alone, you'd think that Cladonia grayi would be relatively easy to distinguish as it can be separated from Cladonia chlorophaea by its colour and more granulose appearance. However, the morpho-complex includes further species that need to be considered; the most likely being Cladonia merochlorophaea, which is very similar. This form is described as having a greenish-brown rather than grey-greenish colouration; shorter stalks with larger cups; a more coarsely granular surface with granulose propagules and minute flaking squamules; sometimes entirely without soredia; and with the base of podetia perhaps more frequently melanized than in true Cladonia grayi.

But, neither species can be distinguished in the field even with spot-testing and, although Cladonia grayi reacts differently to UV light, they can only be reliably identified with TLC (thin-layer chromatology), so have to be recorded here as members of the Cladonia grayi complex.

In fact, Cladonia grayi s.str appears to be the rarest of the heathland 'pixie-cups' with only a small number of confirmed records. Both species favour strongly acidic peat and sandy soils enriched with ligneous debris typical of the habitat of some southern heaths and bogs. There are no records for Ebblake Bog, but the habitat is probably ideal (see Cladonia incrassata for more information about the site). Cladonia merochlorophaea on the other hand has been officially recorded in the New Forest albeit from only a small number of locations, but two of the sites are Strodgemoor Bottom and Pipers Wait, which is why I've included the following photos. Both show at least one podetia where the base is blackened where the squamules have flaked off.

As previously noted, (see Cladonia chlorophaea) members of the Cladonia grayi complex are the most frequent 'pixie-cup' species to be found growing in strongly acid habitats.