GRAPHIS ScnIPTA

On the identity of Ocellularia atlantica Erichs.
PER M. JORGENSEN
While revising the European thelotremes (Purvis
et al. 1994), the tlpe of Ocellularia atlantica
Erichs. was unavailable, and we decided
not to include it in our study since it was
known only from the Canary Islands, and was
recorded with spores quite different from any
European species of Thelotrema.
Hafellner (1995: 95), however, suggested
that it belonged to T. subtile Tuck., a rather
unlikely conclusion as that species has spores
which are considerably smaller than recorded
for O. atlantica. A study of the type now
appeared necessary. With the kind assistance
of Harrie Sipman, Berlin the type from the
Canary Islands (Figure I ) was finally located
in HBG.
Material and methods
The tlpe specimen from HBG was compared
with specimens in BG, hand-sectioned, and
sections in water were studied under different
magnifications in an ordinary light-microscope.
Results
Jorgensen, P. M. 2000: On the identity of Ocellularia atlantica Erichs.
Graphis Scripta I2: l-2. Stockholm. ISSN 0901-7593.
Study of the tlpe of Ocellularia atlantica Erichs. has shown that it is not
Thelotema subtile Tuck. as recently claimed, but instead a species of Porina.
Since it is the oldest name on species level for the long-spored taxa in the P.
nucula Ach. group, the name is transfened to that genus, hopefully stabilizing
the continuously changing nomenclature of that group.
Per M. Jorgensen, Dept. of Botany, University of Bergen, AUdgt. 4I, N-5007
Bergen, Norway.
thick, uneven and coarsely granular with globose,
up to 1 mm in diameter, closed ascomata
(perithecia) with a pinkish brown ostiolar
region. This impression was confirmed by
anatomical studies, though the up to I I -
septate, fusiform spores tend to be on the
broad side for P. heterospora, up to 20 mm
wide, including the 3-4 mm thick perispore.
Since Erichsen's epithet is far older on
species level than any which has been applied
to long-spored specimens of the Porina
nucula Ach. complex, I regard it necessary to
make the formal combination to stabilize the
nomenclature, at least for the taxon distributed
from Macaronesia to SW Ireland (Kalb &
Hafellner 1992:82).
Porina atlantica (Erichs.) P. M. Jorg.
comb. nov.
Ocellularia atlantica Erichs., Hedwigia 66:
276 (1926). - Typus: Canary Islands, Tenerifa,
Llano de los Vieijos in Monte Minas de
Abajo, on Laurus canariensis, 17.Ill.l9l9, L.
Lindiger (HB G-holotypus ! )
Superlicially the specimen is very similar in This would be the name to use for all material
appearance to a lichen I once collected in SW on both sides of the Atlantic according to
Ireland, then named Porina heterospora McCarthy (2000: 6) for what he calls Porina
(Fink) Hanis (Purvis & James 1992: 491). guaranitica Malme in couplet 40' However,
The creamish grey thallus of the type is rather there are divided opinions on the taxonomy in
America (McCarthy 1993, Harris 1995), so