CRAPHIS ScnIPTA - Universitetet i Oslo

46 Ingvar Kcirnefelt and Arne Thell
W
Figure 1. Cetraia peruviana habit (Holotype, FH). Bar L mm.
cilia or projections seen on the margins, pSeudocyphellae
not observed; cortical layers covered
with a distinct epicortex, c. 5 pm thick on
the upper surface and somewhat thinner on
the lower, upper and lower cortical layers c.
20-30 pm thick, composed of 2-3 layers of
pachydermatous paraplectenchymatous cells,
cells in the outer layer large, 5-7 pm in
diameter, algal cells sparse, treborxioid,
medulla rather lar, medullary hyphae thick, c.
5 pm, strongly gelatinized. Apothecia and conidiomata
not observed. Thallus K-, C-, PDand
UV-. Lichesterinic and protolichesterinic
acids present.
This species is only known from the type
collection carrying the unpublished name
Platysma peruvianum given by G. K. Merrill.
The specimen was carefully examined in anatomical,
structural and chemical characteristics.
It reminds a little in thallus morphology of
Cetraria kamczatica although the lobes are
much more curved and shortened (Figure 1).
Furthermore there are also some similarities
with C. nepalensis (Kiirnefelt 1979) although
C. peruviana has much less distinctly canalicu-
GRAPHTS SCRIPTA 5 (1e93)
late and almost subtubular lobes. Unfortunately
the material is very limited and there
were no ascomata or mature conidiomata
found. Some undeveloped marginal pycnidia
were observed, although mature conidia could
not be located. Both ascus structures and conidia
are othenvise characters of major importance
for the recognition of species belonging
to Cetraia (Kiirnefelt et al. 1992, 1993). The
evidence from the anatomical characters of the
thallus in addition to presence of lichesterinic
and protolichesterinic acids are, however,
strong arguments that this species should
actually belong within Cetraria.
There is no information about the habitat
ecology on the label. Cetraia peruviana is,
however, most probably a terricolous species.
There was no information in Soukup (1%5)
that a lichen of this kind was earlier known to
Peru.
Cetraria nivalis (L.) Acharius
Methodus Lichenum, 1803: 293. Basionym:
Lichen nivalb L., Spec. Plant., L753: LL45.