Two Superficially Similar Lichen Crusts, Gregorella humida and Moelleropsis nebulosa, and a Description of the New Lichenicolous Fungus Llimoniella gregorellae

Abstract

Vondrák, J., Palice, Z., Mareš, J. & Kocourková, J. 2013. Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa, and a description of the new lichenicolous fungus Llimoniella gregorellae. — Herzogia 26: 31–48. Although some characters distinguishing Gregorella humida and Moelleropsis nebulosa were previously known, sterile specimens and specimens with poorly-developed apothecia are often difficult to separate. We provide morphological and anatomical characters that will allow reliable determination of such difficult collections. The most important character for determination of sterile thalli is the shape of the mycobiont cells in the thallus granules. A key summarizes the diagnostic characters of G. humida and M. nebulosa (and some similar species). The Nostoc photobiont in G. humida is morphologically similar to Nostoc from M. nebulosa but the two are not closely related within the genus. The ecology of both lichen species is similar, but there are differences in the preference for differently acidic substrates and in co-occurring bryophytes and lichens. In Central Europe, M. nebulosa was frequently collected in the first half of the 20th century, but there are few recent records, whereas G. humida was only occasionally collected before the last two decades, but is now regularly collected. Moelleropsis nebulosa rarely hosts lichenicolous fungi, though we have seen Lichenochora mediterranae (previously known only on Fuscopannaria) and Sarcopyrenia sp. on it. Gregorella humida rarely hosts a single lichenicolous fungus, described here as Llimoniella gregorellae, spec. nova, which causes obvious harm to host thalli; ITS sequences indicate that it belongs in Leotiomycetes.

Full text

Herzogia 26 (1), 2013: 31– 48 31
Two superficially similar lichen crusts, Gregorella humida and
Moelleropsis nebulosa, and a description of the new
lichenicolous fungus Llimoniella gregorellae
Jan Vondrák, Zdeněk Palice, Jan Mareš & Jana Kocourková
Abstract: Vondrák, J., Palice, Z., Mareš, J. & Kocourková, J. 2013. Two superficially similar lichen crusts,
Gregorella humida and Moelleropsis nebulosa, and a description of the new lichenicolous fungus Llimoniella grego-
rellae. – Herzogia 26: 31– 48.
Although some characters distinguishing Gregorella humida and Moelleropsis nebulosa were previously known,
sterile specimens and specimens with poorly-developed apothecia are often difficult to separate. We provide mor-
phological and anatomical characters that will allow reliable determination of such difficult collections. The most
important character for determination of sterile thalli is the shape of the mycobiont cells in the thallus granules. A
key summarizes the diagnostic characters of G. humida and M. nebulosa (and some similar species). The Nostoc
photobiont in G. humida is morphologically similar to Nostoc from M. nebulosa but the two are not closely re-
lated within the genus. The ecology of both lichen species is similar, but there are differences in the preference
for differently acidic substrates and in co-occurring bryophytes and lichens. In Central Europe, M. nebulosa was
frequently collected in the first half of the 20th century, but there are few recent records, whereas G. humida was
only occasionally collected before the last two decades, but is now regularly collected. Moelleropsis nebulosa
rarely hosts lichenicolous fungi, though we have seen Lichenochora mediterranae (previously known only on
Fuscopannaria) and Sarcopyrenia sp. on it. Gregorella humida rarely hosts a single lichenicolous fungus, de-
scribed here as Llimoniella gregorellae, spec. nova, which causes obvious harm to host thalli; ITS sequences
indicate that it belongs in Leotiomycetes.
Zusammenfassung: Vondrák, J., Palice, Z., Mareš, J. & Kocourková, J. 2013. Die beiden oberflächlich ähnli-
chen Krustenflechten Gregorella humida und Moelleropsis nebulosa und die Beschreibung des neuen lichenicolen
Pilzes Llimoniella gregorellae. – Herzogia 26: 31– 48.
Obgleich einige Trennmerkmale zwischen Gregorella humida und Moelleropsis nebulosa schon bekannt waren,
sind sterile Proben und Proben mit schlecht entwickelten Apothecien oft schwer zu unterscheiden. Wir liefern
morphologische und anatomische Merkmale, die eine zuverlässige Bestimmung solch schwieriger Aufsammlungen
erlauben. Das wichtigste Merkmal für die Bestimmung steriler Thalli ist die Form der Mykobiontenzellen in den
Thalluskörnchen. Ein Schlüssel wird präsentiert, der die diagnostisch bedeutsamen Merkmale von G. humida und
M. nebulosa (und einiger ähnlicher Arten) zusammenfasst. Der Nostoc-Photobiont von G. humida ähnelt morpho-
logisch dem von M. nebulosa, aber die beiden sind innerhalb der Gattung nicht näher miteinander verwandt. Die
Ökologie der beiden Flechtenarten ist ähnlich, aber es gibt Unterschiede in der Präferenz für unterschiedlich saure
Substrate und in den als Begleitarten auftretenden Moosen und Flechten. In Mitteleuropa wurde M. nebulosa häufig
in der ersten Hälfte des 20. Jahrhunderts gesammelt, aber es gibt wenige aktuelle Funde. Dagegen wurde G. humida
vor den letzten zwei Jahrzehnten nur gelegentlich gesammelt, wird heute aber regelmäßig gefunden. Moelleropsis
nebulosa wird selten von lichenicolen Pilzen besiedelt; wir haben auf dieser Art Lichenochora mediterranae (zuvor
nur von Fuscopannaria bekannt) und Sarcopyrenia sp. gefunden. Auf G. humida kommt selten ein lichenicoler
Pilz vor, der hier als Llimoniella gregorellae beschrieben wird. ITS-Sequenzen weisen darauf hin, dass er zu den
Leotiomycetes gehört.
Keywords: Arctomiaceae, cyanolichens, Leotiomycetes, lichenicolous fungi, Nostoc, Pannariaceae, photobiont.

32 Herzogia 26 (1), 2013
Introduction
The recent placements of Moelleropsis nebulosa and M. humida, now Gregorella humida, into
two distant families (Lumbsch & Huhndorf 2010) has greatly improved our understanding
of these two species, but some problems remain. There is the practical problem of actually
determining collections, as fertile specimens of both species may be very similar and sterile
specimens even more so. There is the theoretical problem that although the species have simi-
lar ecology (epigeic r-strategists), their population histories are very different.
Originally, we merely sought diagnostic characters in apothecia that would distinguish samples
of M. nebulosa with small immarginate apothecia from G. humida, but we also found charac-
ters in the vegetative thallus that distinguish sterile populations of both species. Photobionts,
ecology and distribution of both species were then also studied to find additional differences.
Our attention was drawn to the need to undertake this work when we encountered a sterile
crust that appeared to be morphologically identical to thalli of M. nebulosa but which proved
to have an ITS sequence (GB KC806067; CBFS JV6995) 100 % similar to the one G. humida
sequence in the GenBank, and unrelated to sequences of true M. nebulosa. This result was
surprising to us, as we had previously known G. humida only with a less developed, brownish
thallus. As we were aware of frequent records of sterile crustose cyanolichens morphologi-
cally identical to M. nebulosa it was clear that the question of how to separate the two species
needed to be addressed.
Previous research on Moelleropsis and Gregorella
Although described in 1871 (as Biatora humida Kullh.; combined into Moelleropsis by
Coppins & P.M.Jørg. in 1993; and into Gregorella by Lumbsch in 2005), G. humida was
rarely collected until Cezanne et al. (2003) published many new records of this taxon from
Germany. Subsequently, it has been collected from many other sites (e.g. Czarnota 2003,
Jørgensen 2007a, Woods 2009, Zimmermann et al. 2011). Ekman & Jørgensen (2002)
published the first molecular data from the species, which revealed that it is not related to
the type species of Moelleropsis, M. nebulosa (Hoffm.) Gyeln., and even falls far outside the
family Pannariaceae. Lumbsch et al. (2005) found that it belongs in Arctomiaceae, close to
Arctomia and Wawea, and transferred it into the new monotypic genus Gregorella.
Gregorella humida has been increasingly recorded during the last two decades, but M. nebu-
losa seems to be almost a forgotten species in most regions of Europe, and there are few recent
records (Ekman et al. 2000). It was not always so. There were many reports since 1794 when
it was first described (as Patellaria nebulosa) until quite recently. Between 1900 and 1940, for
example, it was commonly collected and repeatedly published from the Czech Republic (cf.
Vězda & Liška 1999).
Some recent authors have provided data on characters of M. nebulosa and G. humida. Selected
characters observed in material from Nothern Europe, the British Isles, North America and
Central Europe are given in Table 1 (with references). The descriptions of characters presented
by these authors are surprisingly similar but they sometimes differ from our own descriptions.
Materials and methods
Our morphological data are generated from our own collections and herbarium material from
Central Europe (mainly the Czech Republic) housed in PRA-V, PRC and PRM. We used the
following methods throughout (including for the new lichenicolous fungus). Sizes of apothe-

Vondrák et al.: Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa 33
cia, thallus granules and squamules were measured in the dry state under the stereomicroscope.
All other characters were assessed microscopically (1000× magnified) in water, without any
chemical pretreatment. Measurements are accurate to 0.5 µm (ascospores, vegetative fungal
cells), 1 µm (e.g. vegetative diaspores, cyanobacterial colonies) or 10 µm (larger structures,
e.g. hymenium height and width of exciples). All measurements of cells (ascospores, paraphy-
ses) include their walls. Measurements are given as (min.–) X1–X2–X3 (–max.), where min. /
max. are the extremes from all measurements, X1 is the lowest specimen arithmetic mean
observed, X2 is arithmetic mean of all observations, X3 is the highest specimen arithmetic
mean observed. Ten measurements per specimen were always done in each assessed sample.
Total numbers of assessed samples and standard deviations from all measurements are given
for the individual characters in square parentheses [n; SD]. In some characters (e.g. hymenium
width), only the min.–max. span is provided; these characters are considered less crucial and
were assessed less precisely. Morphological terminology follows Smith et al. (2009). Images
from SEM microscopy were used to show differences in surface structures of thalli of both
species. Methods for high-performance liquid chromatography (HPLC) followed Søchting
(1997). Four samples were analyzed: G. humida “PRA, ZP1858” (apothecia + thallus), “CBFS
JV6984” (thallus); M. nebulosa “PRM 633660” (apothecia + thallus), “PRM832462” (thallus).
Fifteen samples of G. humida and eighteen specimens of M. nebulosa were used for pH mea-
surements of the substrate. The pH was measured in well-mixed suspension of c. 1 ml of dry
soil below thalli and 10 ml of distilled water after 15 min. of intensive shaking. The pH of pa-
per sheets and glue used for fixing old lichen samples was also examined, but their possible in-
fluence on pH of fixed herbarium samples was found to be negligible. Co-occurring bryophyte
species were identified from 12 specimens of G. humida and 22 specimens of M. nebulosa.
The ITS sequences of mycobiont and lichenicolous fungus were generated by direct PCR (e.g.
Arup 2006) with PCR cycling parameters following Ekman (2001). Partial 16S rRNA gene
and adjacent ITS region of cyanobacterial photobionts were amplified following Boyer et al.
(2001), using 10 –20 ng of template DNA isolated directly from the lichen thalli by modified
XS extraction protocol (Yilmaz et al. 2009). The PCR products were cloned using the standard
pGEM®-T Easy vector system, and sequenced on the ABI PRISM 3130xl automated sequen-
cer. Obtained sequences were aligned by MAFFT v. 6 (Katoh et. al. 2009) together with 47
Nostoc OTUs, representing the whole known variability of the genus in GenBank, and two
outgroup taxa. A Bayesian tree was generated in MrBayes v. 3.2 (Ronquist & Huelsenbeck
2003) by running two independent runs of 4 Markov chains for 20 million generations with
sampling frequency of 100, and subsequent majority consensus from the last 75 % of the sam-
pled trees. The node bootstrap supports were calculated using maximum likelihood via phyML
v. 3.0 (GTR+G+I likelihood model, 1000 replicates; Guindon & Gascuel 2003) and maxi-
mum parsimony via PAUP v.4.10b (100 random-addition heuristic searches with TBR branch
swapping, 1000 non-parametric bootstrap replicates; Swofford 2002).
Samples investigated
Gregorella humida: Czech Republic. Central Bohemia. Příbram, Lešetice, SE foot of discharge hopper, c. 0.7 km
W of village, alt. 550 m, 49°38'48''N/14°0'37''E, 26 May 2008, J. Malíček & J. Vondrák (CBFS JV6861, 6866; herb.
Malíček 1260); Ibid.: 11 Feb. 2011 (CBFS JV8370; herb. Malíček 3311); Sedlčany, sand-pit on S edge of town,
alt. 375 m, 49°38'58''N/14°25'28''E, on sandy soil, 14 May 2011, J. Malíček (herb. Malíček 3464). East Bohemia.
Krkonoše Mts, Černý Důl: limestone mining area W of the village, a heaped plateau S of the quarry, N50°37,98'/
E015°42,29', alt. 680 – 690 m, on loamy soil, 10 Jun 2005, J. Liška, Z. Palice & Š. Slavíková (PRA, Palice 8904);
Hanušovice, Chrastice, at village, alt. c. 550 m, 2 Oct. 2008, J. Vondrák (CBFS JV6694). North Bohemia. Jizerské
hory Mts, Janov, Hrabětice, alt. 740 m, 25 Jul 2011 & 29 Apr 2012, Z. Palice (PRA, Palice 14802, 15157). South
Bohemia. České Budějovice, Staré Hodějovice, 1.3 km NW of village (at settling-pit), alt. c. 420 m, 48°57'22.362''N/

34 Herzogia 26 (1), 2013
14°30'37.976''E, 2 Feb. 2011, J. Vondrák (CBFS JV8448); Jindřichův Hradec, Kamenice nad Lipou, „Hutě“ settle-
ment close to vil. Bohdalín, alt. c. 600 m, 49°17'42.96''N/15°0'30.05''E, 1 Sep. 2007, J. Vondrák (CBFS JV5627);
Novohradské hory Mts, Pohorská Ves: open place in managed spruce forest along forestry road at W-facing slope at
foothill of the crest of Mt Stubenberg [A], 2 km SE of Žofín settlement, 48°39'36.5''N/14°42'37.2''E, alt. 805 m, 14
Oct. 2010, Z. Palice (PRA Palice 14284); Prachatice, Husinec, Výrov, in industrial zone at main road between Husinec
and Těšovice, alt. c. 500 m, 26 Nov. 2006, J. Vondrák (CBFS JV4901); Ibid.: 23 Sept. 2007, J. Malíček & J. Vondrák
(herb. Malíček 1011); Ibid.: 13 Apr. 2009 (CBFS JV6986); Týn nad Vltavou, Temelín, at railway between Temelín and
nuclear power-plant „Temelín“, alt. 490 m, 49°11'19''N/14°21'57''E, 4 Apr. 2009, J. Vondrák (CBFS JV6984, 6985,
6992, 6995, 6998, dupl. in Herb. Palice); Ibid.: 16 March 2011 (CBFS JV8445); Volary, c. 2 km S of Černý Kříž, in
sand quarry on bare soil, alt. 775 m, 25 Apr. 1996, Z. Palice (PRA-V 3439; herb. Palice); Ibid.: 17 June 1996 (PRA
Palice 1858). Poland. Gorce Mts: Poręba Wielka, alt. 610 m, 2000, P. Czarnota (PRA Palice, s.n., dupl. ex GPN).
Russia. Southern Urals: Orenburg region, Tyul’gan district, vill. Tashla, Tilia cordata-Acer platanoides-Quercus ro-
bur-Ulmus laevis forest in uppermost stream of brook Kuplya, alt. 400 – 480 m, 52°28'21''N/56°16'36''E, on soil at
forest gravel road, 2011, J. Vondrák (CBFS JV9960).
Moelleropsis nebulosa: Austria. Oberösterreich. Schärding, alt. 540 m, 2001, F. Berger (PRA, Palice 12169). Czech
Republic. Central Bohemia. Beroun, Karlštejn, alt. c. 400 m, 5 June 1933, J. Suza (PRM 633652); Beroun, Karlštejn,
loc. Velká hora, 16 Apr. 1926, J. Klika & A. Hilitzer (PRM 832466). East Bohemia. Vápenný Podol, 1910, V. Kuťák
(PRM 832473); Chotěboř, at railway embankment in forest near the town game-keeper house, 1889, C. Bayer (PRC).
North Bohemia. Česká Lípa, Provodín, loc. Provodínské kameny [Meichelsberg], without date, J. Anders (PRM
832475); Louny, Počerady, village Třískolupy [Schiessglock] destroyed by coal mining, loc. “Hora” [probably the
hill Zvonice, 275 m], without date, J. Anders (PRM 832470). West Bohemia. Kdyně, at pathway to Rýzmberk, 6 Sep.
1936, A. Hilitzer (PRM 832465); Šumava Mts, Čeňkova Pila, alt. 720 m, 23 May 1995, Z. Palice 14890 (PRA). South
Moravia. Blansko, Rájec, 350 m, Apr. 1913, J. Suza (PRM 633662); Boskovice, Borotín, alt. 430 m, on soil at road,
Jan. 1934, J. Dyr [Crypt. Čechosl. Exs. 146] (PRA-V 3433, PRC, PRM 633660, 789732, 832460, 865673); Brno,
Jundrov, at hill Holedná, alt. c. 350 m, 38 March 1918, J. Suza (PRM 633655); Brno, Hády, A. Vězda (PRA-V 3438);
Brno, Jehnice, alt. 300 m, 3 March 1920, J. Suza (PRM 633666); Dukovany, loc. Skryjský mlýn, alt. 280 m, 5 March
1920, J. Suza (PRM 633653); Tišnov, in valley of river Loučka, loc. Bruhalův mlýn, 1921, J. Suza (PRM 633664);
Třebíč, at village Kracovice, alt. 500 m, 19 Aug. 1918, J. Suza (PRM 633661); [Velké Meziříčí], beneath the village
Milasín, 1907, M. Servít (PRC); [Velké Meziříčí], Strážek, valley of river Bobrůvka, Feb. 1909, M. Servít (PRC);
[Velké Meziříčí], Strážek, a mill beneath Mitrov settlement, Aug. 1909, M. Servít (PRC); [Velké Meziříčí], Křížanov,
beneath loc. “Sv. Hora”, at road cutting, (?)1909, M. Servít (PRC) [Servít 1910: 49]; Velké Meziříčí, Horní Bory, alt.
500 m, 1921, J. Suza (PRM 633667); Náměšť nad Oslavou, in forest near Koroslepy (Kuroslepy) SE of Náměšť nad
Oslavou, 1909, M.Servít (PRC); Znojmo, at ruin of Nový Hrádek, on soil, 28 March 1932, J. Suza (PRM 633663).
Germany. Sächs. Schweiz: ad terram arenosam muscosam, L. Rabenhorst [Rabenhorst, Lichenes Europaei Exs. 967]
(PRC). Hungary. Bükk Mts, at village Mályinka, alt. 580 m, 27 Aug. 1937, F. Fóriss (Lich. Bükk. Exs. 6; PRM
832462). Slovakia. Piešťany, at village Hradok, alt. 300 m, Apr. 1933, J. Suza (PRM 633656); Povážský Inovec Mts,
Vozokany, loc. „Marhat“, Aug. 1930, J. Suza (PRM 633657); Slovenské Rudohoří Mts, Košické Hamry, alt. c. 400 m,
27 July 1937, J. Suza (PRM 633659, 832461).
Protopannaria pezizoides – samples incorrectly identified as Pannaria (=Moelleropsis) nebulosa: Czech Republic.
Central Bohemia. Slapy, loc. Svatojánské proudy, 4 Nov. 1934, A. Hilitzer (PRM 832463); Štěchovice, loc. Červený
vrch, May 1935, Nebeský & A. Hilitzer (PRM 832464). East Bohemia. Krkonoše, loc. Kotelní jáma, 9 Sep. 1923, A.
Hilitzer (PRM 832477). North Bohemia. Warnsdorf, 12 July 1923, J. Anders (PRM 832478). South Moravia. Blansko,
in valley of brook Křtinský potok, 10 Oct. 1955, A. Vězda (PRA-V 3436); Velká Bíteš, in valley of river Bitýška, at
village Svatoňov, alt. 450 m, 29 Sept. 1963, A. Vězda (Lich. Sel. Exs. 280; PRA-V 5880).
Results and discussion
Characters of the apothecia
Gregorella humida: Apothecia brown to dark brown, flat or ± convex, (0.2–)0.30 – 0.32– 0.34
(– 0.5) mm diam. [3; 0.09]. Thalline exciple absent. True exciple thin, inconspicuous (Fig.
1E) or absent. Hypothecium pale brown or colourless. Hymenium c. 75 –100 µm high, with-
out pigments, but epithecium brownish. Asci cylindrical, with amyloid external sheath but
with KI– tholus (Fig. 2A). Paraphyses not numerous, conglutinated (individual paraphyses
visible after treatment with KOH), anastomosed and branched, c. 1.5 –3.0 µm wide, with tips
sometimes widened up to 4.0 – 4.5 µm. Ascospores (Fig. 2C) uniseriate or biseriate, colourless,
often with 1–2 large oil drops, (8.5 –)12.4 –14.5 –16.1(–19.0) × (5.0 –)7.1– 8.0 –9.8(–15.0) µm

Vondrák et al.: Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa 35
Fig. 1: Gregorella and Moelleropsis; A – fertile Gregorella, CBFS JV6985; B – sterile Gregorella, CBFS JV8370;
C – apothecia of Moelleropsis with well-developed thalline exciple, PRM 633660; D – apothecia of Moelleropsis
with indistinct thalline exciple, PRM 633655; E – Gregorella, vertical section in apothecium, CBFS JV6985
(in water); F – Moelleropsis, vertical section in apothecium, PRM 633655 (in water). Scales: A–D = 1 mm; E,
F = 50 µm.
F
C
B
D
A
E

36 Herzogia 26 (1), 2013
[7; 2.4 (length); 1.7 (width)]; ellipsoid, tear-
shaped, subglobose or rarely narrowly ellip-
soid; length/width ratio (1.0 –)1.7–1.9 –2.1
(–2.8) [7; 0.6]. Yellow-brown pigment in epi-
hymenium ± intensifying in KOH and HNO
3
.
HPLC did not reveal any substances soluble
in acetone.
Moelleropsis nebulosa: Apothecia pale
brown to dark brown, flat, (0.3 –)0.6 – 0.8 –1.1
(–1.6) mm diam. [3; 0.4]. Thalline exciple
absent in young apothecia but distinct in
older apothecia, c. 40 –170 µm thick, formed
of granules c. 60 –170 µm diam. True exci-
ple well-developed in young apothecia (Fig.
1F; with occasional single-celled colourless
setae, up to about 50 µm long), but reduced
in older apothecia, c. 30 –100 µm thick, with-
out pigmentation in section; its internal part
formed of prosoplectenchymatic hyphae c.
1.5 –3 µm thick, external part ± paraplect-
enchymatous, of cells c. 3 –7 × 4 –11 µm.
Hypothecium yellow-brown or colourless.
Hymenium c. 80 –120 µm high, without pig-
ments, but epithecium brownish. Asci cylin-
drical, with amyloid external sheath and with
amyloid tholus similar to the Porpidia-type
(Fig. 2B). Paraphyses numerous, not con-
glutinated (individual paraphyses well visible
in sections), ± anastomosed and branched, c.
2.0 –3.0 µm wide, with tips not widened. Ascospores (Fig. 2D) uniseriate or biseriate, colour-
less, rarely with oil drops, (12.5 –)14.8 –18.5 –21.8(–25.5) × (5.0 –)6.1–7.0 –7.9(–9.0) µm [10;
3.1 (length); 1.0 (width)]; ± uniform in shape: ellipsoid to narrowly ellipsoid; length/width ra-
tio (1.8 –)2.6 –2.7–2.8(– 4.0) [10; 0.4]. Yellow-brown pigment in epihymenium ± intensifying
in KOH and HNO
3
. HPLC did not reveal any substances soluble in acetone.
Moelleropsis nebulosa is rather variable in the apothecial size and in the degree of develop-
ment of a thalline exciple. While its phenotypes with large apothecia having a well-developed
thalline exciple are easily separated from Gregorella humida, specimens with small apothecia
(0.3 – 0.5 mm diam.), without a thalline exciple and with an indistinct true exciple (Fig. 1D) are
macroscopically very similar to G. humida.
The colour of apothecia varies in both species. In dry conditions pale brown apothecia are
often encountered in M. nebulosa but are very rare in G. humida, while dark brown apothecia
are common in G. humida but rather rare in M. nebulosa.
Ascospore shapes and sizes are variable in both species; differences between extreme width
and length values as well as the span of lowest and highest specimen arithmetic means are
great: 3.7 µm (span of specimen means) and 10.5 µm (min.–max. span) in the ascospore length
of G. humida and 7.0 µm (span of specimen means) and 13.0 µm (min.–max. span) in the as-
Fig. 2: Gregorella humida and Moelleropsis nebu-
losa. A – ascus apex in Gregorella; B – ascus apex in
Moelleropsis; C – ascospore variability in Gregorella;
D – ascospore variability in Moelleropsis. Scale = 10 µm.

Vondrák et al.: Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa 37
Table 1: Characters of Gregorella humida and Moelleropsis nebulosa in various literature sources and in this study.
Gregorella humida
Jørgensen (2007a)
(Nothern Europe)
Woods (2009a)
(Great Britain)
Wirth (1 9 9 5 )
(Central Europe)
This study
(Central Europe)
Thallus granules/
goniocysts
30 – 60 µm diam. 30 – 60 µm diam. thinly granular
(30 –)61– 69 – 81
(–130) µm diam. [4;
23]
Exciple
true exciple soon
excluded; thalline
exciple absent
no margin or margin
soon excluded
not visible
true exciple
inconspicuous or
absent; thalline
exciple absent
Asci ascus apex I–
KI+ ascus wall, KI–
tholus
not considered
with amyloid external
sheath but with KI–
tholus
Ascospores
14 –19(–25)
× 7–10 µm
12.5 –19(–24)
× 6.5 –9.5 µm
14 –19 × 7–9.5 µm
(8.5 –)12.4 –14.5 –
16.1(–19.0) × (5.0 –)
7.1– 8.0 –9.8
(–15.0) µm [7; 2.4
(lenght); 1.7 (width)]
Chemistry
no secondary
substances (by TLC)
no secondary
substances (by TLC)
not considered
Yellow-brown
pigment in
epihymenium and
goniocysts (K+,
N+ intensif.), N±
fleetingly pink;
no substances (by
HPLC)
Moelleropsis nebulosa
Jørgensen (2007b)
(Nothern Europe)
Woods (2009b)
(Great Britain)
Jørgensen (2002a)
(North America)
This study
(Central Europe)
Thallus granules/
goniocysts
to 100 µm diam. 30 –100 µm diam. 30 –100 µm diam.
(40 –)61– 84 –110
(–170) µm diam. [4;
35]
Exciple
true exciple present,
up to 100 µm thick;
often with thalline
grains
true exciple to
100 µm thick,
paraplectenchy-
matous; often with
granular thalline
exciple
true exciple present,
paraplectenchy-
matous; thalline
exciple present
true exciple usually
well-developed;
thalline exciple may
be present in older
apothecia (other
details in the text)
Asci
with apical amyloid
structures
apex with KI+ blue
tholus
apex with I+ blue
apical dome
with amyloid
external sheath
and with amyloid
tholus similar to the
Porpidia-type
Ascospores 10 –15 × 5 – 8 µm
(11–)13 –15(–20)
× 6 – 8 µm
10 –15(–20) × 5 – 8 µm
(12.5 –)14.8 –18.5 –
21.8(–25.5) × (5.0 –)
6.1–7.0 –7.9
(–9.0) µm [10; 3.1
(length); 1.0 (width)]
Chemistry
no secondary
substances (by TLC)
no secondary
substances (by TLC)
secondary metabolites
not detected
as in Gregorella
humida

38 Herzogia 26 (1), 2013
cospore length of M. nebulosa. The ascospore size differs considerably between the species.
The ascospore shape is rather uniformly narrowly ellipsoid in M. nebulosa, as shown by the
length / width ratio: 2.6 –2.8 (span of specimen means). In G. humida, the ascospore shape
varies from ellipsoid to subglobose; the length / width ratio of 1.7–2.1 (span of specimen
means). The considerable variation in published information for ascospore sizes (Table 1)
probably reflects the variation between specimens (and insufficient sampling and averaging).
Characters of the thallus
Gregorella humida: Thallus (Figs 1A, B) blue-grey, brown-grey or olive-grey, granulate
or formed of goniocysts. Granules / goniocysts (30 –)61– 69 – 81(–130) µm diam. [4; 23].
Squamules occasionally present, c. 130 – 430 µm diam. Granules / goniocysts formed of para-
plectenchymatous fungal tissue (Fig. 3A) with colourless, mainly ±isodiametric cells, (3.0 –)
5.6 –5.8 – 6.0(– 8.25) µm diam. [3; 1.4]. Shapes of mycobiont cells globose or variously ir-
regular, but rarely strongly elongated in one direction (Fig. 3C). Paraplectenchymatous tissue
fully covers the surface of granules. Photobiont is the cyanobacterium Nostoc sp. in clusters
enclosed by mucilaginous envelopes. Cyanobacterial colonies (12–)17–19 –21(–27) µm diam.
[3; 5.2]. Yellow-brown pigment often conspicuous, intensifying in KOH and HNO
3
; after
HNO
3
fleetingly pink. HPLC did not reveal any substances soluble in acetone.
Thallus may be infected by a lichenicolous member of the Leotiomycetes, which is described
below and placed in Llimoniella. As the species of Llimoniella are narrowly host specific
(Diederich et al. 2010), we consider infections of this fungus as an additional character for
the identification of sterile G. humida thalli.
Moelleropsis nebulosa: Thallus (Figs 1C, D) blue-grey or brown-grey, granulate or formed
of goniocysts. Granules / goniocysts (40 –)61– 84 –110(–170) µm diam. [4; 35]. Squamules
occasionally present, c. 200 –330 µm diam. Granules / goniocysts formed of prosoplectenchyma-
tous fungal tissue (Figs 3B, D) with variously curved and branched, colourless short hyphae,
(4.25 –)6.2– 6.8 –7.6(–10.0) × (1.75 –)2.8 –3.1–3.4(–5.0) µm [3; 1.7 (length); 0.9 (width)].
Prosoplectenchymatous tissue usually not covering the whole surface of the granules; but photo-
biont sheaths partly forming the granule surface. Photobiont is the cyanobacterium Nostoc sp. in
clusters enclosed by mucilaginous envelopes. Cyanobacterial colonies (11–)24 –26 –27(– 49) µm
diam. [2; 10]. Yellow-brown pigment not always conspicuous, but intensifying in KOH and
HNO
3
; after HNO
3
fleetingly pink. HPLC did not reveal any substances soluble in acetone.
Thallus may be infected by the following lichenicolous fungi. (1) Lichenochora mediterra-
neae Calat., Nav.-Ros. & E.Calvo (observed in sample “PRC: Strážek, 1909, M. Servít“),
characterized by forming small faded galls on host; black, partly to fully immersed perithe-
cia with paraplectenchmatous wall; c. 30 –50 × 4.5 – 6.5 µm, 3-septate ascospores in 2-spored,
unitunicate asci; hamathecium of short indistinct chains of ±isodiametric cells. This fungus is
known from Fuscopannaria (e.g. Calatayud et al. 2000) and we suspect it may be host spe-
cific to Fuscopannaria s.lat. including Moelleropsis. (2) Sarcopyrenia sp. (observed in sample
“PRM832462: 1939, F. Fóriss”), characterized by sessile black perithecia with wall consisting
of dark outer part and colourless inner part, formed of large isodiametric cells (c. 10 –25 µm
diam.); ascospores are acicular, c. 20 –30 × 1.5 –2.0 µm, with rounded ends, arranged in bundle
in unitunicate asci. Host range for this fungus is uncertain; a similar undescribed Sarcopyrenia
is reported from another cyanolichen, Lichinella sp. (Tretiach & Navarro-Rosinés 1996).
Both G. humida and M. nebulosa vary a lot in the size of the granules that form the thallus;
they may have large granules of > 100 µm diam. (more common in Moelleropsis nebulosa),

Vondrák et al.: Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa 39
Fig. 3: Gregorella humida and Moelleropsis nebulosa. A, C – thallus granules in Gregorella; B, D – thallus granules in
Moelleropsis. Scales: A, B = 100 µm; C, D = 10 µm.
DC
A B

40 Herzogia 26 (1), 2013
but also small goniocysts of c. 30 – 80 µm diam. (common in both species). Squamules are
± larger and more frequently observed in M. nebulosa than in G. humida. The colour of the
thalli is also variable; ± brownish (more common in Gregorella) or ± greyish (common in both
species). According to our observations, sterile specimens of both species sometimes cannot
be separated in the field.
Key to the species
We combine here diagnostic characters found in the apothecia and the thalli of both species. For
practical reasons, we also include some similar terricolous species, which might be confused
with the studied species; data for the latter were adopted from Jørgensen (2002b, 2007b).
1 Thallus brownish, rarely with a bluish tinge, with abundant squamules; granules may be present, but
large, usually >100 µm diam. In undisturbed natural habitats .......................................................... 2
1* Thallus variously coloured, but often with a bluish tinge; of isidia or granules (goniocysts) c.
50 –150 µm diam.; squamules may be present, but not abundant. In various habitats. .................... 4
2 Squamules up to 1 mm wide; apothecia with entire or indistinctly granulate thalline exciple; asci
with amyloid sheets but without internal amyloid structures. .................. Protopannaria pezizoides
2* Squamules 1–3 mm wide, thalline exciple often excluded; asci with apical amyloid ring structures .
........................................................................................................................................................... 3
3 Thallus dark brown, in herbarium often covered by tiny terpenoid crystals (terpenoids and fatty
acids detectable by TLC); thallus surface covered by imbricate lobes or granules; in arctic-alpine
habitats. ............................................................................................... Fuscopannaria praetermissa
3* Thallus brown or lead blue, without white crystals on the surface; no secondary compounds by TLC;
margin of squamules dissolve in soredia; not known from Europe ...... Fuscopannaria cyanolepra
4(1) Thallus of granules (isidia), 100 –150 µm diam., with distinct upper paraplectenchymatous cortex of
1–3 rows of cells. .................................................................................................. Vahliella atlantica
4* Thallus of non-corticate granules (goniocysts) c. 40 –150 µm diam. ............................................... 5
5 At least some corticate squamules (c. 1–2 mm in diam.) present in the sorediate crust; not known
from Europe (very similar to Moelleropsis nebulosa) .......................... Fuscopannaria cyanolepra
5* Squamules (if present) smaller, up to 0.5 mm, without distinct cortex. Known from Europe ......... 6
6 Apothecia flat or convex, c. 0.2– 0.5 mm diam., without true and thalline exciples. Ascospores 12–
16 × 7–10 µm (span of mean values; 10 measurements per specimen), variable in shape, but mainly
broadly ellipsoid; length/width ratio 1.7–2.1 (span of specimen mean values). Paraphyses congluti-
nated (individual paraphyses well-visible only after treatment with KOH). Asci with amyloid exter-
nal sheath but without amyloid tholus (Fig. 2A). Granules/goniocysts c. 40 –100 µm diam., formed
of paraplectenchymatous tissue, fully covering mucilaginous envelopes of Nostoc (Figs 3A, C) .....
............................................................................................................................. Gregorella humida
6* Apothecia ± flat, c. 0.3 –1.6 mm diam., always with true exciple, well visible in section (but less
conspicuous in young and old apothecia). Thalline exciple formed of granules, usually absent from
young apothecia but present in older apothecia. Ascospores 14.5 –22 × 6 – 8 µm (span of mean va-
lues; 10 measurements per specimen), (narrowly) ellipsoid; length/width ratio 2.6 –2.8 (span of
specimen mean values). Paraphyses not conglutinated (individual paraphyses well-visible in sec-
tion). Asci with amyloid external sheath and with amyloid tholus similar to the Porpidia-type (Fig.
2B). Granules/goniocysts c. 50 –150 µm diam., formed by short hyphae c. 5 –9 × 2– 4 µm, only partly
covering mucilaginous envelopes of Nostoc (Figs 3B, D) ............................ Moelleropsis nebulosa
Photobionts
Morphological appraisals of photobionts from Gregorella humida and Moelleropsis nebulosa
confirmed that they belong to Nostoc (irregularly coiled filaments composed of ± identical sub-

Vondrák et al.: Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa 41
spherical vegetative cells and intercalary heterocytes, enclosed in gelatinous envelopes). The
observed characters did not allow identification of the Nostoc species or clear morhological
separation of G. humida and M. nebulosa photobionts. The 16S rRNA gene sequences of pho-
tobionts from both lichens apparently correspond to the core cluster of Nostoc, which also con-
tains all sequenced symbiotic members of the genus from lichens and plants (Papaefthimou
et al. 2008). Our phylogenetic analysis of Nostoc s. str. contains two original sequences of
cyanobionts from G. humida (JX129884 – Poland “PRA, Palice, s.n.”; JX129885 – Czech
Republic “PRA, Palice 14802”) and two from M. nebulosa (JX129887 – Austria “PRA, Palice
12169”; JX129886 – Czech Republic “PRA, Palice 14890”). Sequences of photobionts from
M. nebulosa clustered tightly together, whereas the sequences from G. humida are similar but
unresolved within a large subclade. Sequences obtained from M. nebulosa are obviously not
closely related those from G. humida (Fig. 4). Moreover, the similar Nostoc sequences for each
of the studied lichen species suggest possible stringent host specifity in these two taxa.
Ecology
Gregorella humida: The studied samples were collected from barren soil (sand or clay) with
low organic content in e.g. road cuttings, loose grasslands, water ditches, sand-pits and rail-
way embankments. Localities are often in urbanized or agricultural landscapes, but also in
open places in managed forests, from lowlands to mountains (up to c. 800 m). Measured
pH of its substrate was 4.9 –5.9 [data from 15 samples]. Bryophytes present in more than
two samples of G. humida are Ceratodon purpureus, Pogonatum aloides and Bryum sp.
Gregorella humida is often accompanied by other inconspicuous crustose pioneer lichens
which are sometimes termed short-living or ephemeral lichens (Poelt & Vězda 1990). We
have recorded a range of co-occurring lichen species similar to that listed by Cezanne et al.
(2003), but we also recorded Baeomyces rufus, Placynthiella uliginosa, Scutula dedicata and
Vezdaea acicularis.
Moelleropsis nebulosa: The studied samples came from mineral or humus-rich soil (rarely
siliceous pebbles and stones) in quarries, road cuttings, forest edges, and railway embank-
ments. This lichen commonly overgrows bryophytes, which suggests fast growth. Localities
are situated in agricultural or near-natural woodland sites from lowlands to mountains (up to c.
750 m). Measured pH of its substrate was 4.1–5.3 [data from 18 samples]. Bryophytes found
in more than two samples of M. nebulosa are Bartramia pomiformis, Brachythecium albicans,
B. glareosum, B. velutinum, Bryoerythrophyllum recurvirostrum, Bryum sp., Ceratodon pur-
pureus, Hypnum cupressiforme, Racomitrium canescens and Tortula subulata. Other lichens
are only occasionally present in herbarium samples of Moelleropsis; patches of Lepraria and
squamules of Cladonia were sometimes intermingled.
We expected that pH measurements would show more acidic substrata for G. humida, which
is only known from siliceous bedrocks, than for M. nebulosa, which sometimes grows on
soils above calcareous bed rocks (also observed by Pykälä 2007). However, our pH mea-
surements clearly showed the opposite. The presence of different bryophytes with the two
lichens suggests a possible explanation. Although some basiphilous bryophytes were found
in specimens of M. nebulosa, most of the species associated with this lichen are pleurocar-
pous mosses which tolerate low pH and prefer humus-rich soils that may be acidic even
over limestone. Gregorella humida usually grows with only a few pioneer moss species on
mineral soils, only occasionally with pleurocarpous mosses, indicating more stable habitats
with organic soils.

42 Herzogia 26 (1), 2013
Fig. 4: Placement of symbionts of Gregorella humida and Moelleropsis nebulosa in the 16S rRNA phylogeny of Nostoc.

Vondrák et al.: Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa 43
Past and present distribution in Central Europe
We have extensive floristic data only from the territory of the Czech Republic. Moelleropsis
nebulosa was collected repeatedly until about 1970, but we know of only one recent record
(Fig. 5). Gregorella humida was probably not collected from the Czech Republic until 1996
(our data), but the number of known localities has increased in recent years (Fig. 5). Literature
data show similar patterns in other Central European countries.
Moelleropsis nebulosa is considered critically endangered in Austria (Türk & Hafellner
1999), extinct in Belgium and Luxembourg (Diederich et al. 2012), extremely rare in Germany
(Wirth et al. 2011), critically endangered in Slovakia (Pišút et al. 2001), regionally extinct
in Poland (Cieśliński et al. 2006) and vulnerable in Switzerland (Scheidegger et al. 2002).
Evidently M. nebulosa has become scarce during the 20
th
century throughout Central Europe.
Gregorella humida is known only from few old records for Central Europe (most of them
before 1900; cf. Cezanne et al. 2003). A new attention to G. humida was evoked by Poelt &
Vězda (1990) and since that time it has been increasingly recorded (e.g. Ernst 1993, Berger
& Priemetzhofer 2000, van den Boom 2000, Cezanne et al. 2003, 2008, Czarnota 2003,
Sparrius 2003, Zimmermann et al. 2011). This fact does not necessarily mean that G. humida
was rare in the past, especially as it often grows on even less natural sites than M. nebulosa
and such urbanized or agricultural habitats were little investigated in the past. Moreover, G.
humida usually forms less conspicuous crusts than M. nebulosa, and such small lichens were
often not collected in the past.
We have no data on the population dynamics of either species, but we consider the species to
be more or less ephemeral and restricted to human managed habitats at particular stages of
succession. These sites are established by random disturbances and their locations change with
time. The difference in the recent distribution of the studied lichens in Central Europe may be
explained by changing types, strength and frequencies of anthropogenic disturbances in the
landscape from one historical period to another. Broadly speaking, slight and small-scale dis-
turbances in the past have been replaced by stronger and more extensive ones in recent times.
Possibly M. nebulosa cannot tolerate strong disturbance, whereas G. humida can and may even
prefer it. Another possibility is that the strain of Nostoc in M. nebulosa might be more sensi-
tive to air pollution. The reductions in range of the related terricolous lichen, Protopannaria
pezizoides, may have similar causes.
Recent records of abundant G. humida may be only snapshots of a temporary phenomenon.
When we repeatedly visited two localities in the Czech Republic (May 2008/February 2011,
April 2009/March 2011), we observed very different abundances and viabilities of local G.
humida populations. At the earlier visits, large sterile populations were present, with some
apothecia of a lichenicolous fungus. At the later visits, we have seen only unhealthy looking
remnants of populations obviously affected by the same lichenicolous fungus. It seems pos-
sible that the lichenicolous fungus (perhaps in combination with other factors) may seriously
reduce individual populations of G. humida.
Description of the Leotiomycete on Gregorella humida
Llimoniella gregorellae Kocourk. & Vondrák, sp. nov. [MycoBank 801903; ITS sequences of
the holotype: JX996120, JX996122]. (Fig. 6)
Diagnosis: Similar to Llimoniella terricola, but with larger ascomata, 150 – 400 µm diam.,
somewhat thicker paraphyses, 1–1.5 µm in lower part, and longer asci, 55 –90 µm. Host is a
member of Arctomiaceae.

44 Herzogia 26 (1), 2013
Typus: Czech Republic. South Bohemia: Týn nad Vltavou, Temelín, at railway between
Temelín and nuclear power-plant „Temelín“, alt. 490 m, 49°11'19''N/14°21'57''E, on soil on
railway embankment, lichenicolous on Gregorella humida, J. Vondrák, 16.3.2011 (CBFS
JV9955 – holotype; Hb. myco. K & K – isotype).
Description: Fungus lichenicolous on the thallus of Gregorella humida, at first not causing
visible damage to the host (Fig. 6A), but later destroying the thallus (Fig. 6C). Thallus in-
conspicuous; vegetative hyphae indistinguishable within host tissues. Ascomata apothecia,
(110 –)140 –150 –160(–250) µm diam. [2; 39], immersed to sessile, base broadly attached to
the host thallus, roundish, dispersed or in groups, brown to black, matt to slightly shiny, when
wet with dark reddish brown disc. Young erumpent apothecia with rough surface, flat or later
concave with elevated margin.
Exciple c. 20 –50 µm wide, orange-brown in section (Fig. 6B), without hairs, prosoplectenchy-
matous, composed of thin-walled, branched and anastomosing hyphae, 2– 4 µm wide, em-
bedded in dense gel (dissolving in K). Exciple sometimes externally surrounded with thin,
subhyaline necrotic layer, especially in lower part, in contact with host thallus. Basal exciple /
hypothecium up to c. 50 µm high, pale orange brown. Hymenium c. 90 –110 µm high, co-
lourless to yellowish, ± inspersed, strongly gelatinous. Epihymenium pale orange brown.
Paraphyses numerous, simple or branched in upper part, conglutinated in hymenial gel, which
is soluble in KOH. Paraphyses in lower hymenium (1.5 –)2.0(–2.5) µm wide [2; 0.3]; paraphy-
ses tips (1.5 –)2.5 –3.0 – 3.5(– 4.0) µm wide [2; 0.7; measured after KOH treatment].
Asci (Fig. 6D) cylindrical, apically slightly applanate, thin walled, wall not thickened apically,
(40 –)52–53 –54(– 62) × (6.5 –)7.4 –7.7– 8.1(–9.0) µm [2; 6.2 (height); 0.8 (width)].
Ascospores (Fig. 6E) uniseriate, colourless, non-septate, variable in shape, but mostly broadly
ellipsoid to almost globose, usually with a single large guttule; (5.0 –)7.0 –7.3 –7.6(–9.5) × (4.0 –)
Fig. 5: Distribution of Gregorella humida and Moelleropsis nebulosa in the Czech Republic.

Vondrák et al.: Two superficially similar lichen crusts, Gregorella humida and Moelleropsis nebulosa 45
5.3 –5.3 –5.4(–7.0) µm [2; 1.2 (length); 0.9 (width)], ascospore length/width ratio (1.1–)
1.3 –1.4 –1.4(–1.9) [2; 0.2].
Conidiomata not observed, but conidiogenous cells originating in basal exciple, ampulli-
form, orange brown (colour and reactions as for exciple), c. 3 –5 × 2–5 µm. Conidia entero-
blastic, acrogenous, oblong to bacilliform, hyaline, non-septate, about 1.5 µm long. This type
of conidiogenesis was observed in several apothecia and we suggest it belongs to Llimoniella
gregorellae, not to any parasitic hyphomycete.
Reactions: exciple and hypothecium K+ brown-purple (persistent), N+ yellow-orange (persis-
tent); Hymenium and Asci I–.
Phylogeny: We generated three ITS sequences from Llimoniella gregorellae; from samples
CBFS JV9955 (JX996120, JX996122) and JV8374 (JX996121). These sequences are identical
and their closest BLAST results are various unidentified Leotiomycetes (several records with
79 % identity and 99 % coverage). In Myconet (Lumbsch & Huhndorf 2010), Llimoniella is
placed into Helotiales (Leotiomycetes), genera incertae sedis. Our data are probably the first
molecular evidence for placement of Llimoniella into Leotiomycetes, because no Llimoniella
sequences are present in the GenBank.
Remarks: The new fungus very likely belongs to Llimoniella s.lat. as understood by
Diederich et al. (2010). The species is characterized by following characters: (1) cylindric
Fig. 6: Llimoniella gregorellae. A – apothecia on living thallus of Gregorella humida, CBFS JV6984; B – apothecium,
vertical section, isotype; C – apothecia on dead host, holotype; D – ascus with ascospores, isotype; E – paraphyses,
isotype (D, E, observed after KOH treatment). Scales: A, C = 0.5 mm, B = 100 µm, D, E = 10 µm.
A B
C ED

46 Herzogia 26 (1), 2013
thin-walled, non-amyloid asci, without apical chamber, (2) uniseriate, broadly ellipsoid and
small ascospores with a large single guttula, (3) prosoplectenchymatous exciple of thin-walled
orange-brown hyphae, K+ purple-brown, (4) paraphyses tips not distinctly widened.
Two other species of Llimoniella are known from cyanolichens, both without K+ purplish
pigment in the exciple; L. heppiae (Nav.-Ros., Hladún & Llimona) Diederich & Ertz has also
wider paraphyses tips, 5 – 6 µm, longer ascospores, about 10 –13 µm, and darker epihyme-
nium (Diederich et al. 2010), and L. terricola (Arnold) M.Schultz, Diederich & Ertz has
larger ascomata, 150 – 400 µm diam., somewhat thicker paraphyses, 1–1.5 µm in lower part,
and longer asci, 55 –90 µm (Ertz & Diederich 2006). Both fungi are also host specific to
lichens of Heppiaceae (Lichinomycetes) and a visible damage of their hosts was not observed
(Diederich et al. 2010). We suppose that L. terricola is the most similar known species to L.
gregorellae.
Paratypes: Czech Republic. Central Bohemia: Příbram, Lešetice, SE foot of discharge
hopper c. 0.7 km W of village, alt. 550 m, 49°38'48''N/14°0'37''E, on soil at base of hopper,
lichenicolous on sterile crust of Gregorella humida, J. Vondrák, 11.2.2011 (CBFS JV8374,
9953); South Bohemia: Týn nad Vltavou, Temelín, at railway between Temelín and nuclear
power-plant „Temelín“, alt. 490 m, 49°11'19''N/14°21'57''E, on soil on railway embankment,
lichenicolous on Gregorella humida, J. Vondrák, 4.4.2009 (CBFS JV6984, 9954).
Acknowledgements
Linda in Arcadia kindly revised the English. Jiří Košnar identified bryophytes and helped us with interpretation of data
from them. Vojtěch Kasalický assisted with measuring of pH. Jiří Liška helped us with reading of some old herbarium
labels. Jiří Machač assisted by SEM photographing. Pavel Hrouzek performed HPLC chromatography. Jiří Malíček
kindly provided Gregorella records. Our research was supported by the grant GAJU 135/2010/P, the long-term re-
search development project of Institute of Botany AS ČR (RVO 67985939), and institutional resources of Ministry of
Education,Youth and Sports of the Czech Republic.
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Manuscript accepted: 26 March 2013.
Addresses of the authors
Jan Vondrák, Institute of Botany, Academy of Sciences, Zámek 1, 25243 Průhonice,
Czech Republic; Department of Botany, Faculty of Science, University of South Bohemia,
Branišovská 31, 37005 České Budějovice, Czech Republic. E-mail: j.vondrak@seznam.cz
Zdeněk Palice, Institute of Botany, Academy of Sciences, Zámek 1, 25243 Průhonice, Czech
Republic; Department of Botany, Faculty of Natural Sciences, Charles University, Benátská 2,
12801 Praha 1, Czech Republic. E-mail: zdenek.palice@ibot.cas.cz
Jan Mareš, Department of Botany, Faculty of Science, University of South Bohemia,
Branišovská 31, 37005 České Budějovice, Czech Republic; Centre for Phycology, Institute of
Botany ASCR, Dukelská 135, 37982 Třeboň, Czech Republic. E-mail: jan.mares@centrum.cz
Jana Kocourková, Department of Ecology, Faculty of Environmental Sciences, Czech
University of Life Sciences, Prague, Kamýcká 129, 16521 Praha 6 - Suchdol, Czech Republic.
E-mail: kocourkovaj@fzp.czu.cz