Bulletin of the British Museum (Natural History)

LICHEN GENUS MICAREA IN EUROPE 149
Lecidea antrophila Larb. ex Leighton in Trans. Linn. Soc. London (Bot.) II, 1: 242 (1876). Type: Ireland,
West Galway, Mwellan near Kylemore, in the interior of a cave, 1877, C. Larbalestier (BM ex K -
lectotype!; isolectotypes: BM!, BM ex K!).
Lecidea paucula Nyl. in Flora, Jena 59: 573 (1876). Type: Ireland, West Galway, 'Montagnes de Maam'
[Maumturk Mountains], iii 1876, C. Lflr/?fl/e5ner(H-NYL 20090 -holotype!).
Micarea umbrosa Vezda & V. Wirth in Folia geobot. phytotax., Praha 11: 93 (1976). Type: Germany,
Baden, Siidschwarzwald, between Neuhausle and Altglashiitte near St. Margen, 830 m, 2 v 1969, V.
Wirth (hb. Wirth 1609 - holotype!).
Lecidea granvina Vainio in Havaas in Bergens Mus. Arb. 1909 (1): 31 (1909); nom. nudum (Art. 32). Spec.
orig.: Norway, Hordaland, Hardanger, Granvin, 10 xi 1900,7. J. Havaas (BG!).
Lecidea demarginata auct. p.p., non Nyl.; see 'Excluded Taxa'.
Note: typification of Lecidea lutulata. Larbalestier's gatherings in BM and H, that were collected from
Rozel meadow in 1873 and subsequently labelled 'Lecidea lutulata', consist of M. bauschiana, M. lutulata
and M. peliocarpa. The specimen H-NYL 10696 contains M. lutulata only and agrees with the original
diagnosis, e.g. 'hypothecium fusconigricans crassum', and is therefore selected as lectotype.
Thallus effuse, thin (up to 40 /xm thick), ± smooth or finely rimose, usually becoming thicker
(up to 600 jxm thick) and scurfy-granular (but never forming discrete areolae or goniocysts) pale
,
greenish grey or grey-green, sometimes straw-coloured in part, sometimes oxydated (on
ferruginous rocks); in section ecorticate and without an amorphous hyaline covering layer.
Phycobiont not micareoid; cells thin-walled, ± globose, c. 5-12 /xm diam, or ellipsoid and up to
15x8/xm.
Apothecia numerous, convex-hemispherical and immarginate from the start, later becoming
± globose or tuberculate, grey-brown, dark brown or blackish, always turning blackish when
moistened, 0-2-0-4 mm diam, or up to 0-8 mm diam when tuberculate. Hymenium 30-40 ^im
tall; upper part varying from hyaline or pale fuscous-brown through olivaceous to dark
aeruginose, pigment often in patches corresponding to clustered apices of stout paraphyses,
K- , HNO3+ red; lower part hyaline or dilutely coloured. Asci cylindrical-clavate, c. 30-40x7-
10 /am. Spores ellipsoid, ovoid, or sometimes dacryoid, 6-8 (-9) x 2-3 (-3 -4) yam. Paraphyses
rather scanty, of two types: p.p. evenly distributed, irregularly flexuose, simple, or forked or
with short branches (especially in the upper part), sometimes anastomosing, 0-8-l(-l-5) ^tm
wide, apices sometimes irregularly swollen to c. 2 ^tm wide; p.p. fasciculate, mostly simple,
stout, c. 1-5-2 /xm wide, with swollen (to 3 /xm), coherent, pigmented apices. Hypothecium
120-360 /x,m tall, dark and opaque, fuscous- or reddish brown, K- or -I- reddish intensifying (but
never with purple or greenish tinges), HNO3-; hyphae interwoven, but becoming vertically
orientated towards the hymenium, c. 1-5-2 /xm wide but coated with dense brown pigment and
appearing 3-4 /xm wide; ascogenous hyphae with swollen cells c. 2-4 /xm wide. Excipulum not
seen even in sections of young apothecia; the hymenium soon becomes reflexed so as to form an
excipulum-like zone below the hypothecium. Pycnidia often present but inconspicuous, immersed,
blackish, c. 80-200 /xm diam, ostiole often gaping; with a single ± globose locule but
walls often convoluted with up to 5 locules seen in a vertical section; outer walls reddish brown,
K-; inner walls of secondary locules hyaline; conidiogenous cells irregularly cylindrical, often
with 1-2 percurrent proliferations, 7-10x1-1-5 /xm, base sometimes swollen to 2-7 /xm wide;
conidia (mesoconidia) cylindrical, sometimes faintly biguttulate but not constricted in the
middle, (3-8-)4-5(-5-5)x0-9-l-4/xm.
Chemistry: All parts K-, C-, PD-; t.l.c: no substances detected.
Observations: The apothecia of M. lutulata have a similar internal pigmentation to those of M.
botryoides {q. v. ) and M. muhrii {q. v. ), but the species is most often confused with M. sylvicola.
The latter shares the same habitat as M. lutulata, but can be distinguished by its hypothecium
which always has a distinctly green, or rarely purplish, tinge in water mounts or KOH; in HNO3
the pigment(s) turn purple-red. M. sylvicola further differs in its larger spores, taller hymenium,
slightly longer and broader conidia, and presence of greenish pigment in its pycnidial walls. M.
myriocarpa occurs in similar habitats to M. lutulata and has a reddish brown, but never opaque
(in thin section) hypothecium. Furthermore, M. myriocarpa has smaller apothecia, narrower,
often 1-septate spores, and sessile pycnidia with much shorter conidia.