NEW OR INTERESTING BRITISH LICHENS IV
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Lichenologist 11(2): 139-179 (1979)
NEW OR INTERESTING BRITISH LICHENS IV*
B. J. COPPINSf and P. W. JAMES %
Introduction
This contribution to our series of papers describing new or otherwise interesting
British lichens is mainly concerned with the description of 11 hitherto undescribed
species and one new variety, whilst two further species are reported from the
British Isles for the first time, and an additional Pseudocyphellaria species is
recognized. Several of the newly described species are sterile crustose lichens with
Trentepohlia as phycobiont; a key to these is provided by James and Coppins (1979).
In our studies all reactions with iodine (I) have been carried out using 0-5 g iodine : 1-5 g
potassium iodide : 100 ml distilled water. Melzer's iodine solution should not be used as it
sometimes gives different colour reactions to this solution. For the examination of conidio-
genesis and conidia, a solution of 0-5 g erythrosin : 100 ml 10% ammonia solution was
employed.
Caloplaca ulcerosa Coppins & P. James sp. nov.
? Caloplaca pyracea var. leucostigma Erichsen, Annls mycol. 40: 184 (1942); type:-Germany,
Schleswig-Holstein, an Kopfpappeln bei der Lachsmule bei Apenrade [now Denmark:
Laksmelle, near Abenra], 14 September 1913, C. F. E. Erichsen (HBG—holotype).
Thallus effusus, albus, cum soraliis flavo-viridibus vel viridio-albis et distincte ulcerosis
instructus. Apothecia 0-25-0-5(-0-6) mm diam, aurantio-rubescentia, junioria cum margine
thallino albido. Ascosporae 8-12 x 4-6 |xm, septa 3-5(-6) ^m lata. Thallus et soralia K— sed
apothecia K + purpurea.
Typus: Scotia, V.C. 98, Main Argyll: Inverary, Mid Glen Shira, occidentalis e Elrigbeag,
27/13.14, alt. c. 200 m, in Acero pseudoplatano, 25 vi. 1977, P. W.James (BM—holotypus).
Thallus epiphloeodal, effuse, thin, smooth to uneven with shallow pustules,
sometimes becoming rimose, whitish. Soralia numerous, discrete or sometimes
becoming confluent, 0-12-0-3 mm diam, pale yellowish-green or greenish-white,
concave, developing from thallus pustules that split open so that a resultant soralium
is delimited by a reflexed ring of thallus.
Apothecia usually scattered, occasionally more numerous but rarely becoming
confluent and angular, sometimes absent, innate when young, sessile at maturity,
0-25-0-5(-0-6) mm diam. Disc concave at first, soon becoming plane or ± convex,
orange to orange-red. Proper margin prominent in young apothecia, later + level
with the disc or becoming excluded in older, convex apothecia; slightly paler than
the disc when dry, but concolorous when moistened. Thalline margin whitish,
* III in Lichenologist 11: 27-45 (1979).
f Royal Botanic Garden, Inverleith Row, Edinburgh EH3 5LR.
% Department of Botany, British Museum (Natural History), Cromwell Road, London
SW7 5BD.
0024-2829/79/020139 + 40 $01.00/0 © 1979 British Lichen Society140 THE LICHENOLOGIST Vol. 11
concolorous with the thallus, distinct in young emergent apothecia but soon excluded
(when viewed from above) in mature apothecia; occasionally sorediate.
Thallus in part thin, 15-50 jxm thick and devoid of algae, formed of short-celled,
thick-walled hyphae, c. 3-5-8 x 3-4 ;xm. In the presence of the phycobiont, the
thallus becomes thicker (+ pustular in surface view) and up to 70 [xm thick, with an
irregular hyaline cortex, 7-15(-20) ;xm thick, without a well-defined medulla.
Soredia c. 15-30 fxm diam. Phycobiont trebouxioid, cells + globose (5—)7—15 pun
diam.
Thecium 55-60 fxm tall, 1+ persistent deep blue; epithecium yellow-orange,
K + purple; hypothecium 70-100 ;xm tall, hyaline, of short or ± globose-celled
hyphae, cells c. 2-9-5 x 2-4-5 (xm. Excipulum thallinum reduced to the underside
of mature apothecia, with an algal layer 35-60 fxm thick. Excipulum proprium
10-15 [im thick below, widening to 45-70 [xm at the surface of apothecium where
it is yellow orange. Paraphyses simple or sparingly branched below, 1-1-5 ;xm thick,
often forked or branched above; apical cell swollen, often capitate, to 6 fxm wide,
and suffused with yellow-orange pigment; 1-2 subtending cells also rather swollen.
Asci c. 40-50 x 12-14 |xm. Spores polarilocular, ellipsoid, 8-12 x 4-6 [xm (in water);
septum 3-5-5(-6) fxm thick, \-\ length of spore.
Pycnidia immersed, not observed in surface view, but sometimes located in
thallus sections, c. 60-70 jxm diam, hyaline; conidia hyaline, simple, ellipsoid or
ovoid-ellipsoid, c. 2-5-3x0-7-1 txm.
Chemistry: thallus and soralia K —, C —, KC —, P —, UV— ; apothecial disc and
proper margin K + purple.
Caloplaca ulcerosa is closely related to C. holocarpa sens. lat. (incl. C. pyracea
(Ach.) Th. Fr.), but differs in having generally less crowded apothecia and in the
presence of numerous, ulcerous, pale green or yellowish-green soralia. C. ulcerosa
has only been found on the trunks of mature parkland or wayside trees, whereas,
in Britain, C. holocarpa is rarely present on corticate trunks of large trees, being
more usually found on twigs and branches of trees or shrubs, hypertrophicated
lignum, concrete, asbestos and basic or hypertrophicated rocks. The name Caloplaca
holocarpa (e.g. as used by Wade, 1965) may well encompass a number of closely
related species; for example, some saxicolous populations may be referable to
C. lithophila Magnusson. The soralia of C. ulcerosa are small and indistinct, such
that material has often been named as C. holocarpa or C. luteoalba. In the field
abundantly fertile forms of C. ulcerosa strongly resemble C. luteoalba, but that
species is readily distinguished microscopically by its narrowly septate spores.
Caloplaca pyracea var. leucostigma may be synonymous with C. ulcerosa, but our
examination of the holotype proved inconclusive, because the material has been
damaged by invertebrates and no well-formed soralia could be found. However, a
few circular concave depressions on one piece of the type may possibly be the
remains of soralia now emptied of soredia.
The principal phorophytes for C. ulcerosa are Acer pseudoplatanus and Ulmus, but
it has also been found on Juglans and Salix. It occurs in communities belonging to
the Xanthorion parietinae, and associated species include: Bacidia arceutina, B.
naegelii, B. rubella, Caloplaca citrina, C. luteoalba, Candelariella xanthostigma,
Collema subflaccidum, Gyalecta truncigena, Lecania cyrtella, Lecanora dispersa aggr.,
Lecidella elaeochroma, Opegrapha varia, O. vulgata, Pertusaria albescens var.1979 New or interesting British lichens—Coppins & James 141
corallina, Parmelia subaurifera, P. sulcata, Phaeophyscia orbicularis, Physcia
adscendens, Physconia perisidiosa, Xanthoria parietina, and the mosses Neckera
complanata and Tortula laevipila.
Additional specimens examined: V.C. 10, Isle of Wight: west of Niton, 40/50.76, on Ultnus,
28 March 1971, B.J. Coppins & F. Rose (E); Ventnor, Bonchurch, on Ulmus in churchyard,
May 1977, P. W. James & J. Harthan (BM). V.C. 12, N. Hampshire: Laverstock Park,
41/4.4, on Ulmus, 11 January 1971, B. J. Coppins & F. Rose (E). V.C. 23, Oxfordshire:
Stonor Park, 41/7.8, on Juglans, 3 April 1971, B.J. Coppins, D. L. Hawksworth & F. Rose
(BM, E); Cornbury Park, 42/35.18, on Ulmus, March 1976, H.J. M. Bowen (E). V.C. 27,
E. Norfolk: near Waxham, 63/446.249, on Salix, 20 March 1973, P. W. Lambley (NOR).
V.C. 53, S. Lincolnshire: Fosdyke churchyard, 53/3.3, on Acer pseudoplatanus, 8 December
1976, M. R. D. Seaward (hb. Seaward). V.C. 68, N. Northumberland: Tweed Valley,
Carham Park, 36/8.3, on Ulmus and old Acer pseudoplatanus, September 1976, O. L. Gilbert
(E). V.C. 99, Dunbarton: Loch Lomond, Rossdhu Park, 26/3.8, on Acer pseudoplatanus,
9 October 1978, B. J. Coppins (E). V.C. H5, E. Cork: Rostellan, Cork Harbour, on Ulmus,
I. Carroll (E). V.C. H8, Limerick: Castle Connell, on Ulmus with C. luteoalba, March 1845,
/. Carroll (BM, Caloplaca luteoalba folder). V.C. H l l , Kilkenny: near Fiddown, July 1915,
M. C. Knowles (DBN, as 'Placodium luteoalbum' in Knowles, 1929: 262).
Lecanactis subabietina Coppins & P. James sp. nov.
Thallus effusus, albido-griseus. Apothecia ignota. Pycnidia numerosa, aggregata, nigra sed
+ albido-pruinosa, 0-18-0-4(-0-5) mm diam, cum margine seniore reflexescenti. Cellulae
conidiogenae phialidicae, 5-7-8 x 1-7-1-9 |j.m, rarissimo proliferatae. Conidia hyalina, simpli-
cia, cylindrica vel oblongo-ellipsoidea, 3-7-5 x 1-2-1-7 ,um. Thallus K —, C —, sed pruina
K + citrina; acidum confluenticum et lepraricum continens.
Typus: Anglia, V.C. 3, S. Devon: Kingsbridge, Slapton, Slapton Ley, ad corticem
Quercus sp., 4.xii.l970, P. W.James & D. L. Hawksworth (BM—holotypus; Vezda, Lich. sel.
exs. no. 977, sub Opegrapha vermicellifera—isotypi).
Thallus effuse, whitish grey, thin, continuous but often appearing rimose owing
to the development of small fissures in the bark, surface minutely scurfy. In section
thallus c. 20-80 u.m thick, homoiomerous, irregular at the surface and without a
cortex. Phycobiont Trentepohlia sp., cells c. 7-15(-19)x 6-12 fxm, occurring as
single cells or in short chains, but sometimes forming longer, branched filaments
under more shaded conditions.
Ascocarps unknown.
Pycnidia numerous, crowded, more or less sessile, black but covered by a ±
dense coating of white prunia, 0-18-0-4(-0-5) mm diam (including pruina), often
with a pale yellow mass of conidia exuding from the wide ostiole. In vertical section,
120-400 am wide, more or less globose when young (Fig. 1A) then expanding above
to become U - or V-shaped (Fig. IB) and, finally, the upper wall may become
outwardly reflexed (Fig. 1C). Wall dark brown, K + olive-black, H N O 3 - , c. 12-25
am thick, lined throughout by conidiogenous cells. Conidiogenous cells hyaline,
simple, cylindrical, phialidic, 5-7-8 x 1-7-1-9 urn, occasionally undergoing a single
percurrent proliferation with the secondary conidiogenous cell being up to two-thirds
the length of the lower parent cell. Conidia hyaline, simple, more or less cylindrical
or oblong-ellipsoid, 3-7-5 x 1-2-1-7 \xxa..
Chemistry: Thallus K - , C - , K C - , P D - , U V - ; pycnidial pruina K +
lemon-yellow, C - , KC —, PD —. Contains confluentic acid and an accessory
substance UV+ blue (by t.l.c. after sulphuric acid and charring); lepraric acid is
also present (specimens were run in the three basic solvents with Roccella fuciformis
as control; the substance occurring in Schismatomma virgineum, which gives a
10142 THE LICHENOLOGIST Vol. 11
FIG. 1. Lecanactis subabietina, vertical sections of pycnidia. A, Immature. B, Mature. C, old.
a, Pruina; b, conidial mass; c, layer of conidiogenous cells; d, pycnidial wall. Scale = 200 yon.
TABLE 1. The differences between Lecanactis subabietina, L. abietina and Opegrapha
vermicellifera
Lecanactis Lecanactis Opegrapha
subabietina abietina vermicellifera
Pycnidia diam 0-2-0-4 mm 0-2-0-3 mm 0-1-0-25 mm
wall thickness 12-25 p n 25-50 [im 35-50 urn
wall in water mount Dark brown Dark brown Orange-brown
wall in K mount Green-black Green-black Brown
Conidia 3-7-5 x 1-2-1-7 y.m 12-17x2-3 jxm 4-5-6-7 x 1-1-4 ixm
Conidiogenous cells 5-7-8 x 1-7-1-9 |xm 8-12 x 1-9-2-4 ^m 5-7-8x1-2-1-4 y.m
Habitat Dry acid bark; mainly Dry acid bark; Alnus, Neutral bark; Ulmus,
Quercus. Woodland Quercus, Fagus, and Acer, Fraxinus.
species conifers. Woodland Waysides, parkland,
species rarely a woodland
species
Pycnidial pruina K + yellow, C — K —, C + red K-, C-
Chemistry (t.l.c, Confluentic acid, Lecanoric and Two unidentified
m.c.t.) UV + blue accessory schizopeltic acids, pigments ±
(after charring), unknown UV +
lepraric acid substances ( + )
Distribution Western oceanic Western suboceanic Eastern, lowland1979 New or interesting British lichens—Coppins & James 143
similar pale pink spot on prepared plates, is probably related to, but not the same as
lepraric acid; see James and Coppins, 1979.)
Lecanactis subabietina is a distinctive species characterized by an effuse, often
extensive, thin, white-grey, Trentepohlia-contaimag thallus with white-pruinose
pycnidia. However, these features are also shared by two rather common and
widespread species, Lecanactis abietina and Opegrapha vermicellifera. Table 1
summarizes the diagnostic features of the three species. In addition, the pycnidia of
L. abietina and O. vermicellifera do not undergo the marked expansion shown by
those of the new species (Fig. 1). In all three species the mode of conidiogenesis
appears to be much the same, that is, conidia are produced terminally from more
or less cylindrical phialides which may proliferate percurrently; this may be a
1 2 3 4 5 6
FIG. 2. Distribution of Lecanactis subabietina in the British Isles.144 THE LICHENOLOGIST Vol. 11
characteristic feature of most lichenized members of the Hysteriales (see Vobis and
Hawksworth, 1979). A key to these three species and other sorediate crustose
species with Trentepohlia as the phycobiont is given by James and Coppins (1979).
Lecanactis subabietina has undoubtedly been much overlooked, but appears to
have a rather southern and oceanic distribution (Fig. 2). Outside Britain it is known
from France (Bretagne) and the Azores (San Miguel, Lagoa Azul, near Caetanus,
c. 270 m, on trees in private park near Lakeside, 2 April, 1977, P. W.James, BM).
It occurs on sheltered, but not deeply shaded, dry acid bark of old trees, especially
Quercus. Occasionally it may also occur on old decaying fern fronds and Calluna
stems in sheltered sites. Accompanying species include Arthonia impolita, Diploecia
canescens, Enterographa crassa, Lepraria incana, Schismatomma decolorans and
Chaenotheca hispidula. Opegrapha vermicelli/era prefers more shaded conditions and
less acidic, more nutrient rich, bark of, for example, Acer pseudoplatanus and Ulmus
spp.
Two releves for Lecanactis subabietina are given in Table 2.
TABLE 2. Two releves for Lecanactis subabietina
Species Stands
A B
Lecanactis subabietina 3-4 + 0-2
Arthonia impolita + 0-2 3-1
Diploicia canescens 1-2 2-3
Lepraria incana aggr. + 0-3 —
Enterographa crassa — + 0-2
Ramalina farinacea — + 0-1
Lecanactis premnea — + 0-1
Schismatomma decolorans —. 2-1
Hypnum cupressiforme + 0-2 + 0-0
Hedera helix — + 0-0
Stand A. Dorset, Merley, pasture near Merley House, 40/011.981. Quercus robur, incl. 90%
aspect 90°, 0-5 x 0-5 m, cover 90%, 20 January 1979, V. J. Giavarini.
Stand B. As for A except aspect 180".
The material identified as Opegrapha vermicellifera in the studies of Vobis (1977)
on the germination of lichen conidia has subsequently been found to belong to
the newly described Lecanactis subabietina.
Lecanactis umbrina Coppins & P. James sp. nov.
Thallus effusus, pulverulentus, sorediosus, atrobrunneus; prothallus niger; soralia griseo-
brunnea. Apothecia et pycnidia ignota. Thallus K —, C —, KC —, PD — ; medulla et soralia
erosa UV+ glacio-caerulea; acidum schizopelticum et chemicum ignotum continens.
Type: V.C. 45, Pembroke: Nevern, Tycanol, 22/09.36, in sylva ad saxa acida tectissima
impendentia, cum Micarea polioide, 10.xii.1978, P. W.James (BM—holotypus).
Thallus widespreading, mainly sorediate, corticate for only a few mm at the
outermost edge and there thin, dark chocolate-brown, with a matt, slightly tomentose
surface, surrounded by a conspicuous, black or purple-black, somewhat fibrose
prothallus. Inner part of the thallus entirely and continuously sorediate, soredia1979 New or interesting British lichens—Coppins & James 145 forming a thick, to 1 mm high, uneven, pulverulent crust which, in part, becomes coarsely rimose-cracked; glaucous-grey-brown, sometimes with a faint dark brown or yellow mottling, white or glaucous-white when abraded. Soredia variable in size, farinose to coarsely granular, sometimes with a partial veil comprising a thin hyphal tomentum. Apothecia and pycnidia unknown. Phycobiont Trentepohlia, at the edge of the thallus forming contorted, branched filaments with closely adpressed, frequently septate hyphae irregularly distributed over their surface; numerous rather swollen apressoria present, hyphae 1-7-2-0 fxm, apressoria, 20-2-3 ^m thick. Phycobiont cells, 15-18(-25) ;xm with walls 3-3-5 fxm thick, contents bright orange with numerous oil globules. In the vicinity of the prothallus, the hyphae and algal filaments are overlain by an amorphous layer, 3-10 (j.m thick, colourless to pale purple-brown. Soredia clusters of 2-5 algal cells (not in filaments), 9-18(-22) \ira in size, surrounded by more or less closely adpres- sed hyphae. Chemistry: K —, C —, KC —, PD —, medulla and abraded soralia UV + intense ice-blue: contains schizopeltic acid (in substantial quantities) and a series of unidentified, UV+ ice-bJue, and a single UV+ yellow, range of substances (254 mjj.) which largely lose their fluorescent properties after treatment of the plates with sulphuric acid and heat. One spot, the lowest, is UV+ ice-blue on untreated plates, becoming UV+ yellow on treated plates; this substance is also present in Opegrapha gyrocarpa and Lecanactis abietina (see James and Coppins, 1979). Neither gyrophoric nor lecanoric acid is present. Lecanactis umbrina is a very distinctive species conned to acid rocks in two old, very shaded and sheltered woodland habitats. It grows on the undersides of sheltered overhangs, tending to overgrow thalli of Opegrapha gyrocarpa, O. zonata, O. saxigena and species of the Micarea sylvicola aggregate, such as M. polioides, and M. bauschiana. Opegrapha gyrocarpa differs from the new species in having more discrete soralia, often with a distinct ochraceous hue, and a different chemistry, including gyrophoric acid (C + fleeting red-orange). Furthermore, the sorediate areas of this species are UV+ orange-yellow, not ice-blue, at 350 m^. O. zonata has small, mainly discrete, more or less pale lilac-coloured soralia and a different chemistry, including confluentic acid; the medulla and soralia are UV+ (see James and Coppins, 1979). Other specimen examined: V.C. 45, Pembroke: Haverfordwest, Treffgame, 22/95.23, on very sheltered, dry, acid rock underhangs in old wood, alt. 40 m, 8 April 1958, P. W. James (BM). Lecanora quercicola Coppins & P. James sp. nov. Thallus effusus, verruculosus, pallide griseus ad pallide viridio-griseus. Apothecia 0-3— 0-6 mm diam, pallide ad rubro-brunnea, + albido-pruinosa, cum margine irregulari et plerumque crenulato. Ascoporae ellipsoideae, 8—11(—12) x 4-5 \xm. Pycnidia macroconidia continentia in verrucis immersa; pycnidia microconidia continentia minuta, immersa, inconspicua. Macroconidia lunata, 8-12 x 3-4 |im; microconidia falciformia, 8-13 x 0-4 fim. Thallus K + leviter flavus, C - , KC+ leviter flavus, P D - , UV± pallide griseo-albus; tria chemica ignota continens. Typus: Anglia, V.C. 11, Hampshire: New Forest, Beaulieu, Stubbs Wood, Hawk Hill, 41/35.03, ad apricam faciem trunci Querci e margine sylvae, 2.xii.l975, P. W.James (BM— holotypus).
146 THE LICHENOLOGIST Vol. 11 Thallus more or Jess widespreading, effuse, lacking a distinct prothallus, thin, finely verrucose, in scattered or contiguous patches following the contours of the substrate, pale grey to pale green-grey, mostly epiphloeodal or between the super- ficial fibres of the bark substrate. Apothecia numerous, dispersed and discrete, or, in places more or less contiguous, rounded or slightly angular, 0-3-0-6 mm diam. At first innate, eventually becoming more or less sessile and slightly constricted towards the base. Immature apothecia with an irregular, often crenate, grey tinged yellow, thalline margin which is slightly elevated above the disc and thallus, when mature the apothecial margin becoming even, more or less evanescent with increasing convexity of the disc. Disc slightly concave at first, becoming more or less convex at maturity, pale to medium red- brown, rarely flesh-coloured, more or less veiled in a white or faintly yellowish pruina giving at least some of the apothecia a distinctive frosted appearance. Pycnidia of two kinds; those containing macroconidia are enclosed in minute thalline warts with a slightly exposed, sometimes slightly gaping, pale ostiole; microconidia in minute, inapparent pycnidia within the thallus. Thallus c. 100 (j.m thick, upper surface with an amorphous, gelatinized cortex, c. 10 [xm thick, overlying the phycobiont layer which is densely interspersed with angular crystals. Hyphal walls thick, 2-4 (un. Phycobiont trebouxioid, cells 9-13 fxm diam. Thalline exciple poorly developed in young apothecia, containing algal cells only in the lower part abutting the thallus. In mature fruits completely gelatinized, the hyphal lumina appearing netted in a tissue formation corresponding to Henssen and Jahns (1973: 30, fig. 3.5M), very variable in width, 25-50 \x.m wide, containing semi-opaque, dense clusters of crystals. Thecium, including epithecium, (40-)50-65 (xm high, markedly gelatinized. Epithecium pale straw-coloured, occasionally suffused red-brown, coloration external to the paraphyses, outer edge (i.e. surface of the disc) densely encrusted with small, semi-translucent crystals. Hypothecium colourless, 20-25 urn thick, hyphae interwoven above, more or less gelatinized below and with angular cell lumina, distinct from the algal layer immediately below. Paraphyses simple, walls conglutinated within the gelatinous matrix, simple, septate, c. 1 ;j.m wide, not or slightly expanded towards the apical cell, wall of apical cell c. 0.4 y.m thick. Asci clavate, 40-45 x 6-8 fxm, wall c. 1 am thick at the side, to c. 6 (im thick at the apex, with a small internal papilla at the apex when mature. Spores ellipsoid, 8— 11 (— 12) x 4-5 jxm, thin-walled, simple, colourless. Pycnidia of two kinds on the same thallus, containing either micro- or macrocon- idia. Pycnidia forming macroconida flask-shaped, c. 140 u.m high and c. 120 ;j.m broad, with a slightly elevated ostiole covered by a thalline tunic of the cortex, lacking algal cells, hyphae densely compacted and with numerous crystal inclusions. Conidiophore layer thin, 1-3 cells thick, outermost cells with slightly darkened walls, conidiogenous cells sessile, phialidic, with rounded or slightly pointed cells which give rise to curved macroconidia at their apices or the outer edge (Fig. 3). Macroconidia 8-12 x 3-4 fxm, more or less lunate, with more or less acute apices, one of which may be more or less truncated indicating the former point of attach- ment to the conidiogenous cell, non-septate. Pycnidia containing microconidia spherical, c. 70 am diam, conidiophore layer 4-5 cells thick, translucent or straw-coloured at the outer edge. Microconidia sickle-shaped, 8-13 x 0-4 ym, non-septate.
1979 New or interesting British lichens—Coppins & James 147 Chemistry: Thallus K + faintly yellow, C - , KC+ faint yellow, P D - , UV + pale grey-white; contains 3 pigments: a, quenching in UV (254 ma), at level 7 (just below atranorin) in TDA solvent and at 7-8 (above atranorin) in HEF, giving a yellow spot after charring with H 2 SO 4 and heat, b, quenching in UV (254 ma), at level 6 in TDA and 3 in HEF, giving a pink spot after charring, c, UV+ orange spot FIG. 3. Lecanora quercicola. A, Macroconidia. B, Conidiogenous cells. Scale =10 (xm. (254 ma) on unsprayed plate in TDA at level 6, just below substance b. The last two, though present in the type, are often absent in other samples (32 in all). Pigment a alone is also present in Lecanora saligna and is probably responsible for the yellow-brown colour of the thallus and thalline margin; it may prove to be characteristic for the group. Lecanora quercicola has a markedly southern, tending to eastern, distribution in the British Isles (Fig. 4). It is most frequent in the New Forest; records for Wales and Scotland are in error for L. saligna. On the Continent the species has been recorded from France (Morbihan, Pontivy, Foret de Quenecan, abundant on old Quercus at edge of field, 4 March 1970, B.J. Coppins, E; listed as Lecidea cf. vernalis by Coppins, 1971: 161). Lecanora quercicola is a characteristic species of well-lit boles of ancient Quercus in rather dry old parkland or old woodland sites, and was listed by both Rose and James (1974: 18, 26) and Rose (1976: 300) as Lecidea cf. vernalis. It occurs on rather exposed, sunny sides of isolated trees or those at the margins of clearings and glades. The species is, however, tolerant of some shade. A preferred habitat is in shallow, rather Jess roughened, very temporary rain tracks on a well-lit side of the phorophyte. It is frequently associated with Pertusaria species, for example, P. hymenea, P. pertusa, and occasionally, with P. flavida, P. hemisphaerica, P. albescens and P. amara; Rinodina exigua, R. roboris, Buellia punctata and Lecanora expallens are often also present. Other species, such as Pachyphiale cornea, Nephroma laevigatum and the fungus Hysterium pulicare, are faithful to the communities in which Lecanora quercicola occurs.
148 THE LICHENOLOGIST Vol. 11
1 2 3 4 5 6
FIG. 4. Distribution of Lecanora quercicola in the British Isles.
Lecanora quercicola is distinguished by its special affinity for old, rough-barked
broad leaved trees, especially Quercus, in ancient woodland or parkland, as well as
having young apothecia which are more or less innate in the thallus and become
emergent, sessile and immarginate with a convex disc. In immature fruits the thalline
margins are peculiarly irregular-crenate and are pale grey with a distinct yellowish
tinge. The thalline margin incorporates relatively few algal cells which are largely
absent from the more distal parts. The presence of two kinds of pycnidia is note-
worthy; the macroconidia are of an unusual luniform shape which may be a special
characteristic of the Lecanora saligna group to which the present species is obviously
related. The microconidia appear to be characteristic of many corticolous Lecanora
and Lecania species.1979 New or interesting British lichens—Coppins & James 149 The rather common and widespread, but much overlooked Lecanora saligna differs from L. quercicola in several respects: the apothecia mostly retain a distinct thalline margin, even when attaining their maximum diameter (c. 0-8 mm); the thalline margin and disc are scarcely pruinose, even when young; the macroconidia are smaller, 7-8(-9) x 2-2-6 u.m, and arise from more irregular, ampuliform, lageniform to more or less cylindrical conidiogenous cells, 5-5-8 x 2-3 urn. Further- more, L. saligna has a quite different ecology, occurring in wayside situations, for example at the edges of pastureland, on fence rails, lignum or dead bark of wounded trees and old tree stumps. L. saligna is also much more tolerant of sulphur dioxide air pollution than L. quercicola; the former species is often misidentified as L. hagenii, a member of the L. dispersa aggr. which, as a group, has macroconidia of a different shape. Selected specimens of Lecanora saligna consulted: V.C. 14, East Sussex: Lewes, on lignum, J. M. Crombie, Lich. brit. no. 161 (BM, E). V.C. 83, Midlothian: Edinburgh, Corstorphine Hill, 36/20.47, on partially charred decorticate stump by footpath, 3 March 1974, B. J. Coppins 3798 (BM,E). V.C. 85, Fife: Dunfermline, east of Luscar, 36/05.89, on lignum and dead bark of Fagus by road, at edge of pasture, 12 April 1975, B. J. Coppins 795 (BM, E). V.C. 97, Westerness: Glen Nevis, Water of Nevis, 27/13.69, on lignum of Fraxinus by camp site, 24 June 1978, B.J. Coppins 3442 (BM, E). Lecidea carrollii Coppins & P. James sp. nov. (Fig- 5) Thallus endo- vel epiphloeodus, + albus; soralia et isidia desunt. Apothecia 0-2-0-5 mm diam, adnata, pallide ad atrorubro-brunnea, non-pruinosa. Ascosporae late ellipsoideae vel ovato-ellipsoideae, 13-17(-19) x 8-5(-10) ptm. Thallus K - vel leviter flavus, C - , K C - , PD — ; atranorium solum continens. Typus: Hibernia, Co. Cork: Castlebarnard Park (sub Lecidea mutabilis), 1856, /. Carroll (BM—holotypus). Thallus thin, smooth, endophloeodal or becoming epiphloeodal, pale, nearly white, often delimited by a narrow, black prothallus, forming mosaics with associated lichens, without soralia or isidia. Thallus, 30-40 urn thick, without a well-defined cortex or medulla. Phycobiont grass-green, single-celled, cells + globose, thin- walled, 7-10(-12)x7-8[im. Apothecia numerous, mostly scattered, 0-2-0-5 mm diam, sessile, adnate, pale to dark red-brown, epruinose; disc plane or slightly convex, with a thin, persistent, smooth, concolorous margin. Thecium 60-70 fzm tall, hyaline, 1+ persistent blue; epithecium non-granular, dilute red-brown, K + dull brown, HNO 3 -; hypothecium (subhymenium) hyaline, 20-45 um tall, containing abundant, deeply staining (in lactophenol cotton-blue) ascogenous elements, 1+ blue. Paraphyses numerous, 1-5-1-7 um thick, septate, frequently branched below but ± simple above although frequently possessing short anastomosing bridges; apices slightly incrassate to clavate, to 3 urn wide, ± hyaline in pale apothecia, but pigmented with a brown 'apical-cap' in dark apothecia. Exipulum a gelatinous matrix, hyaline within, but red-brown (concolorous with epithecium) at the outer edge; composed of thin, 1-1-5 \xm thick, radiating, branching and anastomosing hyphae, that partially separate in K. Asci clavate to pyriform, 55-65 x 15-20(-28) fj.m; in iodine with an 1+ blue tholus and an I — wall, 1-1-5 y.m thick, that is surrounded by a thin, rather diffuse 1+ blue layer,
150 THE LICHENOLOGIST Vol. 11
FIG. 5. Lecidea carrollii. A, Portion of thecium showing two asci and nearly mature spores.
B, Mature spores. C, Paraphyses tips. D, Apex of semi-mature ascus showing differential
staining with iodine. Scale = 10 |xm.1979 New or interesting British lichens—Coppins & James 151 8-spored. Ascospores broadly ellipsoid or ovate-ellipsoid, hyaline, 13—17(—19) x 8-5-10 y.m, with thick walls, 0-7-1-5 [xm thick. Pycnidia not seen. Chemistry: Thallus K— or K f + yellow, C —, KC —, PD —, I— ; contains only atranorin (by t.l.c). Lecidea carrollii is easily identified by its thin, whitish thallus with numerous small, plane, red-brown apothecia (best seen when wet), and rather large, broadly ellipsoid, thick-walled spores. It shares some similarities with Lecidea tornoensis Nyl.j but that species differs in having markedly convex, immarginate apothecia; larger spores, 15-21 x 10-14 jxm, with thicker walls, 2-3 jj.m thick; broader asci, c. 60-65 x 26-30 (xm; and a darkish brown, uneven to verrucose thallus. In northern Scandinavia L. tornoensis is common on bark (especially Betula and conifers), but in Britain it is not known as an epiphyte and is only recorded from a few sites in the Breadalbane Mountains of Perthshire, where it grows over bryophytes in sheltered rock crevices at altitudes above 800 m. L. tornoensis was transferred to the genus Mycoblastus by Anderson (Anderson and Carmer, 1974), but owing to marked differences from typical members of that genus (e.g. M. affinis, M. sanguin- arius, M. fucatus) in thallus appearance, chemistry and ascocarp pigmentation, we prefer to retain it for the time being within the broad confines of Lecidea s. lat. In addition, the asci in the above Mycoblastus species each have an 1+ deep blue, more or less conical, external cap, that persists during the degeneration of empty asci; such a structure is not seen in either L. tornoensis or L. carrollii. James (Poelt and Vezda, 1977: 169) suggested that Lecidea tornoensis might be a member of the southern hemisphere genus Miltidea Stirton (Stirton 1898: 382). Stirton stated that the type species of his genus was Lecidea rubicatula Stirton and examination of the type material of this species (New Zealand, near Wellington, J. Buchanan, BM—holotype) showed that the dark red apothecia have a densely granular, yellow-brown epithecium, K + purple and a thecium richly interspersed with colourless granules and oil droplets; the hypothecium is opaque, deep yellow- brown ; and the spores are simple, 20-25 x 8-9 ;xm with only a slightly thickened wall. The species contains four unidentified pigments unrelated to the parietin complex. L. rubicatula seems to be allied to Haematomma, although the red pigment is not haemaventosin as in H. ventosum. We consequently now consider that neither L. carrollii nor L. tornoensis is related to Miltidea. Lecidea carrollii has long been known to British lichenologists, and was first reported and illustrated by Carroll (1859), whose material was erroneously named as Lecidea mutabilis Fee by Nylander. In later years it has been known as Lecidea tenebricosa (Ach.) Nyl. (e.g. James, 1965; Duncan, 1970), a name which has also been applied to another species misunderstood by British authors, Lecidea erythrophaea Florke. The material of Lecidea anomala e tenebricosa Ach. in the Acharian herbaria (BM, H) is a mixture of several species (including L. erythrophaea) but does not include L. carrollii. L. carrollii occurs on smooth or slightly rough bark of small trees, or on branches and twigs of larger trees, in moist woodlands especially by streams and in boggy carrs. It is recorded from many localities in south-western Britain (Fig. 6B) and from Bretagne, France (Coppins, 1971: as L. tenebricosa). Reported phorophytes are particularly Salix and Corylus, but also Fraxinus, Quercus, Betula, Fagus and Populus; associated species nearly always include Lecanora jamesii, and often also Arthonia
152 THE LICHENOLOGIST Vol. 11
2 3 4 5 6
FIG. 6. Distribution of Lecidea erythrophaea (A) and L. carrollii (B) in the British Isles.
radiata, Arthopyrenia fallax, Fuscidea Hghtfootii, Lecanora chlarotera, Lecidella
elaeochroma, Parmelia subaurifera and Frullania tamarisci.
Lecidea erythrophaea Florke
in Sommerfeldt, Suppl. Fl. Lapp.: 163 (1826); type: not seen (not found in O or UPS).
Thallus thin, endophloeodal to partially epiphloeodal, smooth to rather uneven
and rimose, whitish, not delimited by a dark hypothallus. Phycobiont grass-green,
cells ± globose, 9-12 jxm diam.1979 New or interesting British lichens—Coppins & James 153 Apothecia numerous, dark reddish brown to brown-black, epruinose, mostly plane to slightly convex with a thin margin, sometimes becoming strongly convex with the margin excluded, 0-4-0-6 (-0-8) mm diam. Thecium 35-45 am tall, hyaline or dilute brownish, I + blue; epithecium brown, K —, HNO 3 — ; hypothecium hyaline or dilute yellow-straw. Excipulum hyaline within, brown (concolorous with the epithecium) at the outer edge; composed of radiating branching and anastomosing hyphae, 1-5-2 am thick, that terminate as swollen brown-walled cells, 3-5-5 am wide at the outer edge. Paraphyses simple or rarely forked, 1-5-2 am thick; apices swollen to 5 am wide and brown walled, occasionally the brown pigment is present below the apices and some paraphyses may become brown-walled throughout. Asci clavate, 30-40x9-12 am, 8-spored. Ascospores fusiform-oblong or fusiform-ellipsoid, (8—)9—12(—14) x 3-4-5 am, thin walled. Pycnidia not seen. Chemistry: thallus K —, C —, KC —, PD —, I—; no substances detected by either t.l.c. or m.c.t. Lecidea erythrophaea is a rare species in eastern Britain (Fig. 6A), although it is rather common in Scandinavia where it occurs on deciduous trees such as Populus and Salix. Most of the British collections were made on Fraxinus, especially the rather smooth bark of young trees in sheltered woodlands. In the field it resembles L. carrollii, with which it has been much confused by British authors, but differs above all in its smaller, thin-walled, fusiform or oblong spores. In Britain L. erythrophaea is commonly associated with Bacidia arceutina, and these two species are scarcely distinguishable without microscopic examination. Lecidea hypopta Ach. has similar dark brown apothecia with oblong-ellipsoid spores, 9-12x4-4-5 am, that often have a brown pigment in their cytoplasm. Confusion with L. erythrophaea is usually avoided, since L. hypopta is mainly confined to the acid bark of Pinus or lignum; it is common in the native pinewoods of Scotland, but is rather rare elsewhere in the British Isles. Selected specimens of L. erythrophaea examined: V.C. 62, North-east Yorks: Great Ayton, Airyholme Wood, 45/5.1, 1852, W. Mudd (E); same locality, W. Mudd, Lich. Brit, exs. no. 163 (sub Lecidea minuta), W. A. Leighton, Lich. Brit. exs. no. 298 (sub Biatora anotnala var. minuta), and no. 326 (sub Biatora anomala Fr. var.) (BM, E). V.C. 96, Easterness: east side of Loch Ness, Inverfarigaig Glen, 28/52.23, on Fraxinus, B.J. Coppins 1982 (E). Micarea pycnidiophora Coppins & P. James sp. nov. (Fig. 7 C-D) Thallus effusus, granulosus, griseo-viridis ad viridis. Apothecia 0-1-0-3 mm diam, globosa ad hemisphaerica, immarginata, ubi sicca pallide eburnea ad carnea. Ascosporae aciculares, 3-5(-7)-septatae, (14-)21-28(-31) x 2-2-5 um. Pycnidia numerosa, sessilia vel stipitata, 01-0-3 mm alta et c. 0-1 mm lata, concoloria cum apotheciis. Conidia cylindrica, 4-6x1 (-1-5) urn, Apothecia et pycnidia K —, C+ rubra, PD— ; acidum gyrophoricum continens. Typus: Anglia, V.C. 11, South Hants: New Forest, Shave Wood, prope Cadnam, 41/29.12, alt. 45 m, ad corticem Fagi, 5 November 1972, B. J. Coppins & F. Rose (E—holotypus; BM—isotypus) Thallus epiphloeodal, effuse, often wide-spreading, continuous, thin, uneven, of more or less coalescing, verrucose granules dispersed on a varnish-like prothallus.
154 THE LICHENOLOGIST Vol. 11
in part rather smooth or mostly uneven, granular or granular-verrucose; dull
grey-green to green, verrucose areas often paler than the main thallus. Often over-
growing the moribund thalli of other crustose lichens and bryophytes.
Apothecia not common but usually abundant when present, small, 0-1-0-3 mm
diam globose to hemispherical, sessile, immarginate, rounded or oval or sometimes
tuberculate in outline, discrete but often becoming contiguous and occasionally
FIG. 7. A-B, Micarea stipitata (holotype). A, Conidia. B, Conidiogenous cells. C-D, M.
pycnidiophora (holotype). C3 Conidia. D, Conidiogenous cells. Scale =10 y.m.
laterally fused. Entirely pallid ivory to pale flesh-coloured when dry, translucent
and grey-green when moist; surface minutely roughened.
Pycnidia always numerous, scattered or contiguous, erumpent from thalline
granules and the surface of the thallus, sessile or shortly stalked, 0-1-0-3 mm high,
c. 0-1 mm broad, globose to shortly elongate, apex rounded or slightly tapered,
concolorous with the apothecia. Stipitate pycnidia usually with a simple stalk
(pycnidiophore) but occasionally clustered and appearing as if branched at the base.
Thallus poorly organized, consisting of more or less contiguous glomerulae
containing algal cells encapsulated by the mycobiont. Algal cells 4-8 u.m diam.
Hyphae closely contiguous with the algal cells.1979 New or interesting British lichens—Coppins & James 155
Thecium 35-50 fxm tall, colourless, 1+ persistent blue; epithecium colourless,
non-granular, outer edge irregular, delimited by a hyaline gelatinous extension of
the thecium. Paraphyses and asci coherent in a gelatinous matrix, indistinct in water
mounts but readily discernible in K mounts, richly branched and anastomosing,
septate, apices not swollen, 1-1-5 ;xm wide, not extending to the outer edge of the
gelatinous matrix (epithecium). Asci clavate, 30-35 x 10-12 jxm, wall 1-5-2 [xm
below, gradually thickening to 3(-4) [xm at the apex (in lactophenol cotton-blue),
8-spored; in iodine immature asci have an I + deep blue tholus, an I — inner wall
and an 1+ blue, rather ill-defined, outer wall. Ascospores straight and vertically
aligned in the ascus, not spiralled, shortly acicular, one end broadened and more
obtuse than the other, 3-5(-7)-septate, septa thin but usually distinct in lactophenol
cotton-blue, (14-)21-28(-31)x 2-2-5 fxm,
Hypothecium hyaline, of very thin, more or less vertically aligned, hyphae, c.
20-30 [xm tall, often infiltrated by clusters of algae from below. Excipulum poorly
developed, c. 10 [xm wide; of branched and anastomosing, outwardly radiating
hyphae in a gelatinous matrix, c. 1 fxm wide, readily separating in K.
Pycnidial wall c. 20-25 fxm thick, hyaline, semi-translucent, composed of very
closely compacted and densely interwoven hyphae, c. 1-1-5 (xm wide. Conidiogenous
cells simple or sometimes branched, more or less cylindrical, phialidic, 6-10 x 1-
1-8 fxm. Conidia hyaline, straight, cylindrical, eguttulate, 4-6 x 1(—1-5) jxm.
Chemistry: K—, C + red (apothecia and pycnidia), PD—; contains gyrophoric
acid (t.l.c).
Micarea pycnidiophora is a relatively inconspicuous species characterized by the
abundance of whitish, more or less stalked pycnidia, the micareoid structure of the
apothecia and the shortly acicular, attenuated spores. It most closely resembles
M. stipitata (see below), which differs in having more elongate and often distinctly
branched pycnidiophores, longer conidia (6-8 \xm), and apothecia and pycnidio-
phores which are C— (i.e. lacking gyrophoric acid). Furthermore, M. pycnidiophora
has a more southern distribution than M. stipitata (see Fig. 8).
A species of old woodland, Micarea pycnidiophora occurs in damp, sheltered and
rather shaded situations. It is generally found on areas of smooth-bark on the
boles of old trees, especially Fagus and Ilex, but also Alnus, Quercus and Rhodo-
dendron. Although characteristic of acid bark the new taxon has not yet been recorded
on conifers. Associated species include Cladonia polydactyla, C. squamosa, Graphis
elegans, Haematomma elatinum, Hypogymnia physodes, Micarea peliocarpa*, M.
prasina aggr., Parmelia perlata, Parmeliopsis hyperopta, Thelotrema lepadinum,
Hypnum cupressiforme var.filiforme, and Lejeunea ulicina. The species has a markedly
southern distribution in Britain (Fig. 8A) and appears to be most abundant in the
New Forest, Hampshire; it was included under 'Bacidia sphaeroides agg.' by Rose
and James (1974: 17). Outside the British Isles the species is known from
Bretagne, being recorded as 'Bacidia sp. 2' by Coppins (1971). It has also been
found in the Canary Islands (Tenerife, woods by road to San Andres, below el
Bailadero, 1970, P. W.James, BM).
*Micarea peliocarpa (Anzi) Coppins & R. Sant. comb. nov. [basionym: Bilimbia
peliocarpa Anzi, Atti Soc. ital. Sci. nat. 9: 250 (1866).—Lecidea violacea Crouan ex Nyl.,
Flora, Jena 45: 464 (1862); non Massal., Ric. Lich. Crost.: 69 (1852).—Micarea violacea
(Crouan ex Nyl.) Hedl., Bih. K. Svenska VetenskAkad. Hand!. 18, 3(3): 91 (1892)].156 THE LICHENOLOGIST Vol. 11
1 2 3 4 5 6
FIG. 8. Distribution of Micarea stipitata (B) and Af. pycnidiophora (A) in the British Isles.
Micarea stipitata Coppins & P. James sp. nov.
(Plate 1; Fig. 7 A-B, 9)
Similis Micareae pycnidiophorae Coppins et P. James, sed ascosporae (17-)20-30(-35) x
2-2-5(-3) |xm, pycnidia valde distincte stipitata, et conidia majora. Pycnidia 0-4-0-8 mm alta
et 0-07-0-1 (-0-15) mm lata, plerumque ramosa. Conidia cylindrica ad anguste ellipsoidea,
6-8 x 1-1-8 [j.m. Apothecia et pycnidia K —, C —, PD— ; sine materia chemica.
Typus: Scotia, V.C. 98, Argyll: Loch Creran, Glasdrum National Nature Reserve,
27/0.4, ad corticem Betulae, 27 May 1976, L. Tibell & Coppins 2357 (E—holotypus; BM, H,
UPS, hb. Poelt, hb. Vezda—isotypi).
External appearance and internal anatomy of the thallus and apothecia as in
Micarea pycnidiophora. Ascospores very similar but often slightly larger, (17-)20-
30(-35) x 2-2-5(-3) [xm. Apothecia often absent.1979 New or interesting British lichens—Coppins & James 157
Pycnidia always abundant, borne on distinct whitish stalks (pycnidiophores)
which are simple, bifurcate or to 5-branched, mainly 0-4-0-8 mm tall and 0-07-
0-l(—0-15) mm broad, often with small irregular clusters of more or less superficially
encapsulated algae. Pycnidiophores composed of more or less randomly orientated
PLATE 1. Micarea stipitata. A, Tuberculate apothecia. B, Branched pycnidia. A-B, x 10.
FIG. 9. Micarea stipitata (holotype). A, Portion of thecium showing mature and immature
asci. B, Ascospores. Scale = 10 pn.
11158 THE LICHENOLOGIST Vol. 11 closely compacted hyphae, 1-1-5 (j.m wide. Pycnidia embedded near the apex or apices of pycnidiophores, ± globose, 70-90 [xm diam; wall hyaline, c. 15 jj.m thick. Conidiogenous cells simple or more rarely branched, more or less cylindrical, phialidic, 7-10 x 1-4-2 [j.m. Conidia straight, cylindrical to narrowly elliptical, eguttulate, 6-8 x 1-1-8 y.m. Chemistry: K - , C —, K C - , P D - ; no lichen substances detected by t.l.c. Micarea stipitata is a distinctive species closely related to M. pycnidophora, characterized by the pallid more or less globose apothecia and the concolorous, markedly stipitate pycnidia. Like M. pycnidiophora, it is frequently without apothecia. For the differences between the two species see under M. pycnidiophora. This species is characteristic of acid, often leached, bark, or overgrowing bryo- phytes on trees in undisturbed woodland in areas with a high rainfall. Micarea stipitata exhibits a marked preference for Betula, but has also been recorded on Alnus, Quercus, Abies and Pinus. Associated species include: Lejeunea ulicina, Frullania species, Dicranum majus, D. scoparium, Hypnum cupressiforme, Isothecium myosuroides, Cladonia squamules (e.g. C. polydactyla, C. squamosa), Cystocoleus niger, Gyalideopsis anastomosans, Hypogymnia physodes, Lecidea granulosa, Lepraria incana aggr., Micarea prasina aggr., Parmelia saxatilis, P. revoluta, Parmeliella jamesii, Platismatia glauca, Stenocybe septata and Thelotrema lepadinum. The British distribution of Micarea stipitata is distinctly more northern and western as well as oceanic than that of M. pycnidiophora (Fig. 8B). It occurs as far north as Loch Erribol, Sutherland, and the most southern record is from near Dolgellau, Merioneth. The species has not yet been found in western Ireland or south- west England but presumably occurs in these areas, especially as it has been recorded from the Canary Islands (Tenerife, El Topo, alt. 1200 m, on Erica arborea, 14 April 1978, P. B. Topham, E). There is also a considerable possibility that M. stipitata will be discovered in western Norway. Mycoblastus sterilis Coppins & P. James sp. nov. Thallus albus ad pallide griseus, plerumque prothallo nigro delimitatus, areolatus. Soralia exorientia areolo, virido-alba, flavo-alba ad griseo-brunneascentia vel caeruleogriseascentia. Apothecia et pycnidia ignota. Thallus et soralia K + flavescentia, C —, KC —, PD + rubescentia; atranorium et acidum fumarprotocetraricum continentia. Typus: Cambria, V.C. 48, Merioneth: Ffestiniog, Coed Cymerau, 23/68.42, ad corticem Betulae, April 1971, B.J. Coppins 2772 (E—holotypus). Thallus corticolous, sometimes lignicolous, crustose, very variable, epiphloeodal or epixylic, sometimes penetrating the substratum, sorediate, often delimited by a distinct black hypothallus (0-1-0-3 mm wide) and mosaic-forming, but sometimes effuse, or (in shaded situations) forming ± orbicular patches without a black prothallus on smooth bark. Thallus beginning as small, convex, grey-white to grey, matt or slightly glossy areolae, c. 0-1-0-35 mm wide, usually soon becoming contiguous to form an uneven rimose crust, or becoming more strongly convex and forming a warty-verrucose crust. In more reduced forms that sometimes occur on shaded smooth bark, the areolae may remain scattered with algae-free patches be- tween which are bluish-grey owing to the presence of dark prothalline hyphae ramifying over or through the uppermost layer of the bark. Soralia developing from
1979 New or interesting British lichens—Coppins & James 159 upper surface of areolae, at first delimited, ± excavate to slightly concave, 0-14— 0-5 mm diam, more rarely becoming markedly convex and to 1 mm diam, often becoming confluent, sometimes giving rise to a continuous, bluish or brownish grey, granular-sorediate crust. Soralia greenish or yellowish white, but often becoming bluish or brownish grey due to a pigment in the external soredia. Thallus c. 60-300 am thick (excluding soralia), heteromerous; algal layer irregular, c. 30-100 um thick; cortex poorly defined, c. 10-25 um thick, of inter- woven, short-celled hyphae; medulla white, almost absent to 200 ^m thick, often penetrating the outer layers of the substrate, consisting of scattered hyaline hyphae, 2-3-3 am wide, obscured in a dense matrix of minute, non-wettable, variously shaped crystals (mostly below 5 x 4 um) which do not dissolve in K, HNO 3 , acetone or ethanol. Prothalline hyphae (if evident) dark greenish grey, HNO 3 + red, 2-5-5 urn wide. Phycobiont ? trebouxioid, cells single, broadly ellipsoid to globose, 7—14(—17) x 7-13 um, with thick walls, c. 1-2 urn thick. Soredia c. 200-40 am diam, composed of a cluster of algal cells encapsulated within closely applied, short-celled hyphae; cells c. 4-7 x 2-5-4 um, hyaline or, in externally situated soredia, becoming dark bluish or brownish grey, HNO 3 + red. Ascocarps and pycnidia not observed. The thallus is often host to two lichenicolous fungi, Tremella sp. and 'Beloniella' sp. Chemistry: thallus and sorelia, K + yellow, C - , K C - , P D + red, I - , U V - ; atranorin and fumarprotocetraric acid by t.l.c. Mycoblastus sterilis is widely distributed and common in many parts of Britain (Fig. 10) and north-west Europe, occurring north of the arctic circle in Swedish Lapland. It is found most frequently on smooth bark, or the flat upper surface of rough bark, but is not uncommon on lignum of decorticate trees and fence posts and rails; it has only once been seen on conifer bark (Picea). It has a rather wide ecological amplitude, occurring in old and secondary woodlands, moist woodland carrs, wayside trees, and isolated trees in exposed moorland situations. In non- polluted areas it occurs on trees with acid to neutral bark, such as Alnus, Betula, Castanea, Carpinus, Fagus, Ilex, Quercus, Salix and Sorbus aucuparia. It may also be found on trees with a normally higher bark pH, e.g. Acer, Fraxinus and rarely Ulmus, where the bark has been acidified due to excessive leaching or by air pol- lutants. In moderately polluted districts it sometimes becomes a co-dominant species in communities including Lecanora conizaeoides, Hypogymnia physodes, Buellia griseovirens and Haematomma caesium. Other species commonly associated with M. sterilis in the British Isles are Catillaria griffithii, Lecanora chlarona, L. expallens, Graphis elegans, Ochrolechia turneri, Rinodina efflorescens, Evernia prunastri, Parmelia saxatilis, P. subaurifera, P. sulcata, Platismatia glauca, Dicranoweisia cirrata and Hypnum cupressiforme. Additional associate species on lignum include Lecanora varia, Lecidea symmicta aggr., Micarea denigrata, Ochrolechia androgyna, Xylographa abietina, X. vitiligo and Bryoria fuscescens. Although M. sterilis is now common and widespread, no specimens collected before 1955 (V.C. 17, Surrey: Shere, Bentlys, Hurt Wood, 51/0.4, on young Quercus, April 1955, J. R. Laundon 1107, BM) have been found. In common with Lecanora conizaeoides, Chaenotheca ferruginea and Parmeliopsis ambigua, it has markedly and rapidly increased in abundance in many parts of the country. Until recently it has been much misunderstood, no doubt due to its great variability linked
160 THE LICHENOLOGIST Vol. 11
2 3 4 5 6
FIG. 10. Distribution of Mycoblastus sterilis in the British Isles.
with a rather wide ecological amplitude, and specimens of it have previously
commonly been assigned to Buellia griseovirens and Fuscidea lightfootii. Reports of
P D + red soralia in F. lightfootii (e.g. Laundon, 1963) are due to confusions with
M. sterilis and Rinodina effiorescens.
M. sterilis has not been found with apothecia or pycnidia, but does resemble in
thallus structure or chemistry some species of Mycoblastus, such as M. affinis and
M. fucatus. However, such resemblances may be merely superficial and the new
species may prove to belong elsewhere, for example, in Buellia or Lecanora.
Apart from its morphological features, M. sterilis is readily separated from
Fuscidea lightfootii and Haematomma caesium (Coppins and James, 1978) by the
PD + red reaction. Buellia griseovirens has a thinner thallus and smaller and more1979 New or interesting British lichens—Coppins & James 161
consistently delimited soralia, K + yellow, P D + yellow (atranorin and norstictic
acid). Other sterile crustose lichens occurring on acid bark or lignum with PD +
red, delimited soralia include Mycoblastus fucatus (lignum only), Rinodina efflorescens
(see below), a Pertusaria sp. on Betula, Sorbus and Pinus in the Scottish Highlands,
and a group of very similar species, some of which have been referred to Lecidea
cinnabarina by British authors. (The status of the latter in the British Isles is under
investigation; some of the material on smooth bark in Scotland appears not to be
that species but a representative of a seemingly undescribed genus.)
In northern Britain, Norway and Sweden, M. sterilis has been found with black
apothecia-like structures, 0-2-0-6(-l) mm diam. However, when wet these structures
become soft and gelatinous, and on close examination prove to be the fruit-bodies of
an apparently undescribed Tremella lacking clamp-connections and with 2-celled
basidia (Fig. 11). It recalls T. simplex Jacks. & Martin, a fungicolous, host-
FIG. 11. Tremella sp. on Mycoblastus sterilis (Coppins 3921, E). A, Immature and mature
basidia. B, Conidiospores. Scale = 10 \i,m.
specific parasite of Aleurodiscus amorphus (Corticiaceae) (Torkelsen, 1968). This
seems to be the first report of a lichenicolous member of the Tremellales. The lichen
thallus appears to be little affected, and the Tremella can probably be regarded as a
parasymbiont. M. sterilis is also host to another parasymbiont (or weak parasite)
with small, immersed apothecia, with ellipsoid, simple, biguttulate ascospores,
6-7-5 x 3-4-5 \>.m. It is related to 'Beloniella' nitschkei (Korber) Rehm, which occurs162 THE LICHENOLOGIST Vol.11
on the thallus of Thelotrema lepadinum (see Hawksworth, 1975). In addition, three
related species are known on Buellia punctata, Haematomma caesium and Pertusaria
hymenea; their taxonomy will be dealt with in a separate publication.
Extra-British specimens of M. sterilis examined: Norway: Vest-Agder, Sogndalen,
Birkelandsvatn, alt. 50-100 m, on smooth bark, with Tremella sp., 1 August 1978, T.
Tensberg 3201 (BM).—Sweden: Norrbotten, Tarendo par., 6-5 km south of Masugusbyn,
Rissa Nature Reserve, 67° 24' N, 22° 03' E, alt. c. 300 m, on trunk of Betula with Lecidea
fuscescens, L. tornoensis and Parmeliopsis ambigua, with Tremella sp., 16 July 1977, B. J.
Coppins & L. Tibell (E); Uppland, 10 km north of Osterbybruk, Norrberget, on Corylus with
Buellia griseovirens and Haematomma elatinum, with Tremella sp., 10 July 1977, B.J. Coppins
& L. Tibell (E), and Stavby, woods north-west of Vasby, on lignum of fence-rail, with
Tremella sp., 9 July 1977, B.J. Coppins (E).—Denmark: Jylland, Viborg, Hald, Langskov,
Egedal, on Populus tremula, 8 August 1977, F. Rose (hb. Rose), and Engesvang, Stenholt
Skov, on Quercus, 24 May 1976, F. Rose & M. Skytte Christiansen (E.)—France: Normandie,
Orne, Foret d'Andaine, on Fagus with Haematomma caesium, 30 July 1978, F. Rose (hb. Rose).
Opegrapha corticola Coppins & P. James sp. nov.
Thallus effusus, griseus ad brunneo-griseus. Soralia numerosa, coalescentia, ulcerosa,
pallide hinnulea vel pallide ochracea. Apothecia et pycnidia ignota. Thallus et soralia K —,
C —, KC —, PD— ; plerumque sine materia chemica, rarissimo cum duobus chemicis ignotis.
Typus: V.C. H3, West Cork: quattuor milia occidentalis e Baltimore, in Populo nigra
prope oram, 27.ii.1965, P. W. James (BM—holotypus).
Thallus corticolous, widespreading, effuse, continuous, thin and closely following
the contours of the substrate, partly endophloeodal, surface smooth, matt, some-
times becoming scabrid-granular, grey in shaded situations, becoming darker and
with a brown tinge in more exposed situations. Prothallus absent, or, if present, more
or less evanescent, inapparent, pale grey. Soralia numerous, randomly distributed,
very variable, at first minute and fleck-like, becoming confluent to form patches
2-3 mm diam, eventually coalescing into irregular, ulcerose, pale fawn to pale brown
yellow or pale ochre-coloured (pale cream-coloured in the herbarium) areas, appear-
ing mostly as plane, or excavate, or sometimes convex, eroded patches.
Apothecia and pycnidia not known.
Thallus not corticate, consisting of intricately contorted hyphae, more or less
enveloping cells of the phycobiont {Trentepohlia sp.); cells of phycobiont 10-17 jj.m
diam, walls c. 2 am thick. Soralia fine-granular, individual granules 20-30 [i.m
diam, often coalescing to form coarser aggregates.
Chemistry: K —, C —, KC —, PD —, UV—; no lichen substances detected by
t.l.c. or m.c.t., or (rarely) two unidentified UV+ red spots on untreated assays.
This new species is distinguished by the corticolous habit, the large, irregular,
eventually ulcerose, fawn to ochre-yellow soralia, and the presence of Trentepohlia
as the phycobiont. O. corticola most closely resembles O. gyrocarpa, normally a
saxicolous species, which may occasionally occur on smooth bark of trees, such as
Ilex, Sorbus aucuparia and Betula, particularly near water in well-wooded moun-
tain valleys and sheltered moist woodlands, in western areas of Britain. In O.
gyrocarpa the soralia are C + orange-red, due to gyrophoric acid, and are UV +
bright pale yellow (possibly due to an unidentified xanthone); schizopeltic acid is
also present. By contrast, the soralia of O. corticola are C— and U V - ; t.l.c. assays
sometimes reveal two unidentified pigments. Furthermore, O. corticola favours
the dry bark of well-lit, mature, wayside trees, especially in coastal areas, althoughYou can also read
