ASCOMYCOTA | LECANOROMYCETES > LECANORALES > Parmeliaceae

Genus Cetraria, meaning 'shield' - apparently, from the shape of the apothecia

Common name:            Spiny Heath-lichen

Synonyms:                    Coelocauon aculatum, Cornicularia aculeata

Habitat:                         Heathland, upland moors

Substrata:                     Acid soil

Growth form:                Terricolous

Thallus type:                  Foliose

Apothecia:                    Very rare

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

Thallus often only loosely attached, forming shrubby, sparsely to well-branched small bushes or tufts from 3-5cm high; the main branches somewhat flattened, irregular in section up to about 1mm dia., furrowed and pitted, minor branches more rounded and even, terminating in short blunt spines; surface shiny, glistening in sunlight, duller in shade; reddish to chestnut brown in colour; usually with some elongated, white pseudocyphellae in pits and hollows within the main branches.

A relatively robust species characteristic of high quality short-grazed heaths and acid grasslands; also, locally occurring on coastal sand dunes and stabilized shingle. Widespread and reasonably common in upland and northern areas on heather moors, but declining in the south. There are a few locations within the New Forest where it has been recorded, but to date this is the only small example that I've found. On heaths that are within the burn cycle it is pretty much confined to refuge areas such as path edges.

During the hotter and dryer summer months it has a tendency to shrivel when it may be even more difficult to locate amongst other ground level vegetation.