A CONSPECTUS OF THE LICHEN GENUS STEREOCAULON ...

I. MACKENZIE LAMB: A Conspectus of Stereocaulon 291
Finland, Norway and Sweden : 133 (I 973). - Stereocaulon coralloides [subsp.]' delisei (BORY) NYL.
Synopsis Methodica Lichenum, 1 (2): 242 (I 860). - Leprocaulon delisei (BORY) OLIV. Expod Systkmatique
et Description des Lichens de l'Ouest et du Nord-Ouest de la France, 2 (4): 378 (1903).
Typus: France, Dept. Calvados, Vire, leg. DELISE and DESPREAUX (PC, fide DODGE, 1929, p. 116;
not seen by us. We have however studied the authentic, possibly isotype material distributed in DEL.
Lich. de France no. 18, from the same locality).
Exsicc.: DEL. Lich. de France Fasc. I (1828) no. 18 (authentic, possibly isotype material) (FH). -
HAV. Lich. EXS. Norveg. no. 608 (1939) (BG, WS).
Icon.: FREY 1932, fig. 14. - KERSH. 1960, fig. 6. - Oz. et CLAUZ. 1970, fig. 387 C. - DAHL et
KROG 1973, fig. 40. - NYL. 1860, PI. VII, fig. 17 (ceph. algae), as St. coralloides subsp. delisei.
Mat. chim. : atranorin, rangiformic acid, norrangiformic acid, and an unidentified fatty
acid.
Distrib.: France, England, Scotland, Norway, Sweden, Madeira, South Africa. Unverified record:
Italy (JATTA, 1909-11).
Remarks: a rare suboceanic species, closely related to St. corticatulum NYL.; the only
member of the subgenus Holostelidium found in Europe. Cephalodia (not always present)
similar in appearance and structure to those of St. corticatulum. Apothecia were previously
unknown in this species, but a specimen in BM from Scotland, Argyll, Strontian, on boulders
from lead mine spoil heaps, leg. P. W. JAMES, 1962 (no. 295) is fertile. Apothecia scarce,
terminal, up to ca. 1 mrn diam., convex, irnrnarginate. Central cone compact, sordid isabelline;
hypothecium colorless, hyaline; hymenium (somewhat immature) ca. 60 p high. (No
mature asci or spores found.)
10 1. Stereocaulon didymicum LAMB (n . sp .)
Diagn.: Pseudopodetia caespitosa, erecta aut partim subdecumbentia, substrato arcte
affixa, 2.0-3.5 cm longa, 0.8-1.0 mm crassa, teretia, subsimplicia vel irregulariter aut subdichotomice
ramosa, vel in toto corticata vel partim decorticata, omnino glabra, sordide
cinerascentia. Phyllocladia (passim parcissime evoluta) cylindrico-coralloidea, simplicia vel
parce ramosa, longit. 0.5-1.5 mm, crassit. ca. 0.2 mm, laevia et corticata, in partibus superioribus
pseudopodetiorum breviora et verruculosa aut passim omnino deficientia (habitu macrocarpoideo).
Cephalodia lateralia, sessilia subsessiliave, latit. 0.7-1.5 mm, isabellino-albescentia
aut cinerascentia, haud nitida, primum laeviuscule subglobosa, dein mox scrobiculato-corrugata
(ut in St. ramuloso), sacculata, intus laxe contexta, cortice 30-60 p crasso,
nec palisadico nec gelatinoso, sordide nubilato et lamina tenui viso fere opaco, hyphis valde
pachydermaticis 5-9 p latis contexto. Apothecia terminalia, 0.8-2.0 (-2.3) mm lata, e plano
mox pileato-convexa et immarginata, fusconigricantia. Conus centralis sat compactus et
dense cinerascenti- aut isabellino-nubilatus. Hypothecium sordide nubilatum aut fuscescens
sed haud vere pigmentiferum (KHO fere decoloratum). Hymenium 75-90 {L altum. Sporae
rectae aut subrectae, 34-septatae, aciculari-fusiformes, longit. 32-50 p, crassit. 3.0-3.5 p.
Atranorinum, acidum didymicum, acidum sticticum et substantiam ignotam acido didymico
affinem geret (KSsubflavescens, PDi-aurantiaco-rubescens). - Habitu statum minorem St.
ramulosi var. macrocarpi (RICH.) BAB. in memoriam revocans, St. rubiginoso PERS. vere arctius
affine (ut e structura corticali cephalodiorum videtur), sed materiis chimicis et distributione
geographica diversum.
Typus: Costa Rica, Prov. Cartago, between Palmital and La Sierra, altit. 1800 m s. m., on steep
stony roadside soil bank, leg. I. M. LAMB and U. V. METZGER, 1969 (FH, holotypus; DUKE, isotypus).
Mat. chim.: atranorin, didymic acid, stictic acid, and an unidentified substance related to