A CONSPECTUS OF THE LICHEN GENUS STEREOCAULON ...

232 Journ. Hattori Bot. Lab. No. 43 1977
MAGN. belongs to St. saxatile, being an environmentally produced modification due to development
among erect moss-stems and lichens (Polytrichum, Cladinae, Cornicularia etc.) which
constrain the pseudopodetia to grow separate and f vertically. RASANEN (1939a) claimed
that St. paschale f. squamescens NYL. refers to this species, and used the epithet Stereocaulon
squamescens (NYL.) RKs. for it in preference to St. evolutoides, an illegitimate procedure if
NYLANDER'S forma should really belong here, which seems somewhat doubtful (see p. 323).
Fo. sorediatum (MAGN.) LAMB (n. comb.)
Basionym: Sfereocaulon paschale f. sorediafum MAGN. Goteborgs K. Vetensk.- o. Vitterh.-Samh.
Handl. ser. 4, 30 (7): 51 (1926).
Typus: Sweden, Varmland, par. Sillerud, near Jarnsjon, leg. A. H. MAGNUSSON, 1912 (UPS-MAGN,
holotypus).
Remarks: the type specimen belongs to St. saxatile, and is typical of the species as it
commonly occurs except in the presence of a number of globose, farinose, well-delimited
soralia mostly crowded together in one place on the surface. MAGNUSSON regarded it as a
monstrous condition. In addition to the type material, we have seen 2 other specimens, both
also from Varmland but from different localities, and they are exactly similar. This very
local occurrence suggests the possibility of dissemination from a single mutant.
Fo. paschaleoides (HAv.) LAMB
ex POELT, Be~timrnung~schIii~~e1 Europaischer Flechten: 644 (1969). - Stereocaulon evolutoides var.
paschaleoides HAV. Arbok Univ. Bergen, Naturvitensk. Rekke, no. 12: 17,20 (1954).
Typus: Norway, Granvin, Gamladaemmo, near Skilsaete, "on moss- and lichen-covered gneiss
boulders", leg. J. HAVAAS (date ?) (UPS-MAGN, CAN, isotypes).
Exsicc.: Lichenotheca Fenn. Fasc. XXXI (1953) no. 757, as St. tomentosum (FH); Fasc. LII (1960)
no. 1278, as St. paschale (FH).
Remarks: a puzzling form agreeing in morphological characters with St. saxatile, but
pale-colored as in St. paschale (L.) HOFFM., not slate-gray as is normal for St. saxatile. The
tomentum is however gray. It seems to be almost intermediate between the two species, or
might even be regarded as belonging to St. grande (MAGN.) MAGN. Specimens referable
here have been seen from Sweden, Norway, Finland, Estonian SSR, Canada (Ontario, Labrador,
Manitoba) and U.S.A. (New York, Wisconsin).
30. Stereocaulon sibiricum LAMB (n. sp.)
Diagn. : Pseudopodetia erecta, caespitosa, substrato arcte affixa, 1.5-2.5 cm longa, 0.4-
1.0 mm crassa, teretia, rigida et quasi lignosa, decorticata, omnino glabra, irregulariter ramosa.
Phyllocladia lateralia, apices pseudopodetiorum versus aggregata, basin versus rarescentia;
minuta, primum granuliformia, ad 0.1 mm lata, dein coralloideo-ramosa, ad 0.4 mm longa
(ut in St. subcoralloidi NYL.) aut etiam interdum lobato- vel digitato-squamulosa. Cephalodia
numerosa, conspicua, lateraliter sessilia vel brevissime pedicellata, grisea, fuscocinerascentia,
fusca aut aeruginoso-nigrescentia, pulvinata subglobosave, 0.5-1.0 (-2.0) mm lata, superficie
scabrida vel minute tuberculato-verruculosa, Stigonema continentia. Soredia desunt. Thal-
lus primarius mox evanescens, e phyllocladiis parvis, digitato-ramosis, leviter complanatis,
sax0 horizontaliter adpressis. Apothecia terminalia, parva, ad 1 mm lata, fusca vel fusco-
nigra, primum plana et margine integro pseudothallino pallidiori circumdata, tandem pileato-
convexa et immarginata. Conus centralis incolor, compactus, gelatinosus. Hypothecium