Bulletin of the British Museum (Natural History)

132 BRIAN JOHN COPPINS
Catillaria elachista var. carbonicola Vainio in Acta Soc. Fauna Fl. fenn. 57 (2): 458 (1934). Type: Finland,
Tavastia australis, Korpilahti, 'hiiltyneella kannolla', 1873, E. A. Lang [Vainio] (H-NYL 19143 -
isotype!).
Notes on the typification o/Biatora elachista Korber. In the protologue to B. elachista, Korber (loc. cit.)
gives the following habitat and locality information: 'On alten Striinken der Castanea vesca bei Heidelberg
von Hrn. v. Zwackh und Ahles aufgefunden.' Material borrowed from the Korber Herbarium (L)
consisted of four specimens: i. bei Heidelberg, Zwackh, annotated: 'Biatora elachista Kbr. nov. sp.' (L
910, 138-101). ii. Heidelberg, Ahles (L 910, 138-100). iii. identical label as ii. (L 910, 138-32). iv.
Forstrevier Goleow bei Rybnik, iii 1872, B. Stein (L 910, 138-298). (i-iii) are on Castanea lignum and (iv) is
on conifer lignum.
The most obvious choice for lectotype is (i) but it is not a Micarea and does not conform to the usual
interpretation of the name (e.g. Vainio, 1934: 45; Ozenda & Clauzade, 1970: 401). I do not know the
identity of this species, but it may be close to Lecidea hypopta Ach. ; a brief description follows:
Thallus probably mostly endoxylic but obscured by a pale farinose crust of a non-lichenised alga.
Apothecia numerous, reddish brown to brown-black, epruinose 0- 15-0-3 mm diam. Young
apothecia with a pale margin which is soon excluded as the disc expands and becomes convex.
Epithecium reddish brown, turning olivaceous brown in K. Hymenium 30-35 /u,m tall. Paraphyses
simple or forked in their upper part, c. 1-1-5 ^tm wide; upper 5-15 ^tm often with pigmented walls
and up to 2-5 /x,m wide. Asci clavate 28-35x10-11 /xm, 8-spored. Spores simple or l-(rarely 2-)
septate oblong-ellipsoid, straight or slightly curved, contents often becoming brown, 8-13x3-4 /u,m.
Excipulum hyaline within, reddish brown at edge, often with a penetrating algal layer c. 25 )u,m wide.
Algal cells c. 7-13 ^tm diam. Pycnidia not found.
Specimens (ii) and (iii) are presumably those that Korber attributed to Ahles in the protologue and are
therefore syntypes. Both belong to the species generally known as Catillaria elachista (Korber) Vainio, and
it is with these that the name is lectotypified here. Specimen (iv) is not a syntype and does not belong
to either of the above taxa. It has small, brown thinly white-pruinose apothecia, a dark reddish
brown hypothecium and small, ellipsoid spores, 7-8x2-5-3 /am, and is referable to Lecidea apochroeella
Nyl.
Thallus effuse, superficial, consisting of dispersed to continuous, convex to subglobose
areolae; areolae greenish white or whitish grey, sometimes tinged grey-brown or olivaceous,
occasionally dark brown (when on burnt lignum), matt, sometimes ± white-pruinose, c.
0-08-0-16(-0-25) mm diam. Areole in section (Fig. IC) with a c. 10-12 /u,m tall, hyaline or
greyish (pigment in gel-matrix, K+ violet), algal-free 'cortex', composed of interwoven, hyaline
hyphae (c. 1-5 ^tm wide) that separate in K; outer surface of cortex sometimes bound by a
hyaline, amorphous, densely gelatinised layer ('epicortex'), c. 3-5 /xm tall. This organised
structure with a 'cortex' and 'epicortex' is often disrupted by the invading torulose hyphae of a
dematiaceous hyphomycete. Phycobiont micareoid, cells 4-7 jxm diam.
Apothecia usually numerous, immarginate, convex to ± globose, often becoming tuberculate,
dark brown to brown-black, matt, (0-08-)0- 12-0-3 mm diam, or to 0-8 mm diam when
tuberculate. Hymenium 30-40 />tm tall. Upper part (epithecium) usually well defined, up to
12 jxm tall, dark fuscous-brown; pigment concentrated into dense amorphous clumps, but
dissolving and fading into solution (without changing colour) in K, HNO3— and not dissolving;
epithecium of young apothecia sometimes Kf+ violet due to the additional presence of the dull
olivaceous, K-l- violet pigment which occurs in greater concentrations in the pycnidia. Remain-
ing (lower) part of hymenium, hyaline with dilute yellowish brown vertical streaks. Asci clavate,
23-35x10-12 jxm. Spores fusiform, oblong-fusiform or ovoid-oblong, often slightly curved,
mostly 0-1-septate and slightly constricted at the septum, (9-)ll-15(-19)x2-3'5 jxm; occasionally
becoming 2- or 3-septate and up to 20-24 /xm long; old spores sometimes with brownish
contents. Paraphyses numerous, hyaline throughout, 0-8-1 /u,m wide in mid-hymenium but
gradually widening above to l-7(-2) /xm; sparingly branched and sometimes anastomosing, but
becoming richly branched above where their entangled apices, together with the brown
pigment, form a ± well delimited epithecium. Hypothecium 60-150 /xm tall, pale, tinged dilute
yellowish brown, K— , HNO3-; hyphae hyaline, 1-1-5 /xm wide, interwoven, becoming ±
vertically orientated towards the hymenium; ascogenous hyphae with swollen cells, mostly 2-