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The new genus and species Deltopyxis triangulispora is described. It is so far known from 14 sites in the south of Luxembourg and one in the neighbouring region of France. The discomycete forms very small, blackish-brown apothecia on bark, more rarely on wood, but par-ticularly on more or less strongly senescent hymenia of Vuilleminia spp. The apothecia occur on dead, cor-ticated, internally very slightly to rather strongly white-rotten, attached or broken, periodically dry branches at a height of about 1–3 m above ground. In most of the collections Vuilleminia was present and covered the bast on one side of the branch, while the periderm still covered the remaining areas. D. triangulispora is so far recorded on angiosperm shrubs of the genera Corylus, Crataegus, Ilex, Prunus, and Salix, which had an ad-vanced age or were already dead. The species prefers undisturbed, usually thermophilous hedges or open woodlands, especially close to their edges, but some-times occurs also in dense, more air-humid woods. The fungus is characterized by 64-spored, elongate sac-cate, short-stalked, inamyloid, rather thin-walled asci which arise from croziers and open at the apex by a broad slit-like pore. The hyaline ascospores have a dis-tinctly triangular shape when seen in profile view, but look slightly flattened, (ellipsoid-)deltoid in front view. In the living ascus they are arranged in a dense elon-gate cluster, which is forcibly discharged as one entity. The position of Deltopyxis within the Ascomycota is unknown. Kurzfassung: Deltopyxis triangulispora gen. et sp. nov., ein viel-sporiger, Tromeropsis-ähnlicher Discomyzet von unklarer systematischer Stellung Die neue Gattung und Art Deltopyxis triangulispora wird beschrieben. Bislang sind 14 Standorte im Süden Luxemburgs und eine in der angrenzenden Region Frankreichs bekannt. Der Discomyzet bildet sehr kleine, schwarzbraune Apothezien auf Rinde, seltener Holz, und besonders auf mehr oder weniger stark gealterten Hymenien von Vuilleminia-Arten. Apothezien traten aus-schließlich auf toten, berindeten, intern leicht bis ziem-lich stark weißfaulen, ansitzenden oder gebrochenen, wiederholt trockenfallenden Ästen in einer Höhe von ungefähr 1-3 m über dem Boden auf. In den meisten Kollektionen war Vuilleminia auf einer Seite des Asts vorhanden, während das Periderm den Bast auf den verbleibenden Astflächen noch bedeckte. D. triangulis­ pora konnte bislang auf Angiospermen-Sträuchern der Gattungen Corylus, Crataegus, Ilex, Prunus und Salix nachgewiesen werden, welche ein fortgeschrittenes Alter zeigten oder bereits abgestorben waren. Die Art bevorzugt ungestörte, normalerweise wärmeliebende Hecken oder offene Wälder, vorzugsweise in Wald-randnähe, kommt aber manchmal aber auch in dichten, luftfeuchteren Wäldern vor. Der Pilz ist gekennzeichnet durch 64-sporige, länglich-sackförmige, kurz gestielte, inamyloide, ziemlich dünnwandige Asci, die aus Haken entstehen und sich apikal mittels eines schlitzförmigen Porus öffnen. Die hyalinen Ascosporen haben in Profil-ansicht eine deutlich dreieckige Form, während sie in Rückenansicht leicht abgeflacht, (ellipsoid-)rauten-bis drachenförmig aussehen. Im lebenden Ascus sind sie in einer dichten, länglichen Traube angeordnet, welche als eine Einheit aktiv abgeschossen wird. Die Position von Deltopyxis innerhalb der Schlauchpilze ist unbekannt.
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Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. 175
Abstract
The new genus and species Deltopyxis triangulispora
is described. It is so far known from 14 sites in the south
of Luxembourg and one in the neighbouring region of
France. The discomycete forms very small, blackish-
brown apothecia on bark, more rarely on wood, but par-
ticularly on more or less strongly senescent hymenia
of Vuilleminia spp. The apothecia occur on dead, cor-
ticated, internally very slightly to rather strongly white-
rotten, attached or broken, periodically dry branches at
a height of about 1–3 m above ground. In most of the
collections Vuilleminia was present and covered the
bast on one side of the branch, while the periderm still
covered the remaining areas. D. triangulispora is so far
recorded on angiosperm shrubs of the genera Corylus,
Crataegus, Ilex, Prunus, and Salix, which had an ad-
vanced age or were already dead. The species prefers
undisturbed, usually thermophilous hedges or open
woodlands, especially close to their edges, but some-
times occurs also in dense, more air-humid woods. The
fungus is characterized by 64-spored, elongate sac-
cate, short-stalked, inamyloid, rather thin-walled asci
which arise from croziers and open at the apex by a
broad slit-like pore. The hyaline ascospores have a dis-
tinctly triangular shape when seen in profile view, but
look slightly flattened, (ellipsoid-)deltoid in front view.
In the living ascus they are arranged in a dense elon-
gate cluster, which is forcibly discharged as one entity.
The position of Deltopyxis within the Ascomycota is
unknown.
Kurzfassung
Deltopyxis triangulispora gen. et sp. nov., ein viel-
sporiger, Tromeropsis-ähnlicher Discomyzet von
unklarer systematischer Stellung
Die neue Gattung und Art Deltopyxis triangulispora
wird beschrieben. Bislang sind 14 Standorte im Süden
Luxemburgs und eine in der angrenzenden Region
Frankreichs bekannt. Der Discomyzet bildet sehr kleine,
schwarzbraune Apothezien auf Rinde, seltener Holz,
und besonders auf mehr oder weniger stark gealterten
Hymenien von Vuilleminia-Arten. Apothezien traten au
s-
schließlich auf toten, berindeten, intern leicht bis ziem-
lich stark weißfaulen, ansitzenden oder gebrochenen,
wiederholt trockenfallenden Ästen in einer Höhe von
ungefähr 1-3 m über dem Boden auf. In den meisten
Kollektionen war Vuilleminia auf einer Seite des Asts
vorhanden, während das Periderm den Bast auf den
verbleibenden Astflächen noch bedeckte. D. triangulis-
pora konnte bislang auf Angiospermen-Sträuchern der
Gattungen Corylus, Crataegus, Ilex, Prunus und Salix
nachgewiesen werden, welche ein fortgeschrittenes
Alter zeigten oder bereits abgestorben waren. Die Art
bevorzugt ungestörte, normalerweise wärmeliebende
Hecken oder offene Wälder, vorzugsweise in Wald-
randnähe, kommt aber manchmal aber auch in dichten,
luftfeuchteren Wäldern vor. Der Pilz ist gekennzeichnet
durch 64-sporige, länglich-sackförmige, kurz gestielte,
inamyloide, ziemlich dünnwandige Asci, die aus Haken
entstehen und sich apikal mittels eines schlitzförmigen
Porus öffnen. Die hyalinen Ascosporen haben in Profil-
ansicht eine deutlich dreieckige Form, während sie in
Rückenansicht leicht abgeflacht, (ellipsoid-)rauten- bis
drachenförmig aussehen. Im lebenden Ascus sind sie
in einer dichten, länglichen Traube angeordnet, welche
als eine Einheit aktiv abgeschossen wird. Die Position
von Deltopyxis innerhalb der Schlauchpilze ist unbe-
kannt.
Autoren
Ha n s -ot t o Ba r a l , Blaihofstr. 42, Tübingen, D-72074
Germany, E-Mail: zotto@arcor.de
Gu y Ma r s o n , 45 B, rue de Bettembourg, Hesperange,
L-5810 Luxembourg
1 Introduction
During various searching trips for desiccation-
tolerant ascomycetes on xeric (= exposed, peri-
odically dry), dead branches, the second author
discovered in 1991 a very small blackish-brown
discomycete with polysporous asci and triangu-
lar spores, which could not be identified with the
consulted literature. It somewhat resembled the
unispecific genus Tromeropsis sH e r w o o d . How-
ever, a number of characteristics deviate from
Tromeropsis, therefore, we place this apparently
undescribed species in a new genus.
In most of the collections the species was found
fruiting on the hymenia of slightly to very strongly
decayed Vuilleminia. This saprobiontic corticioid
Deltopyxis triangulispora gen. et sp. nov.,
a polysporous Tromeropsis-like discomycete
of unclear relationship
Ha n s -ot t o Ba r a l & Gu y Ma r s o n
176 andrias, 19 (2012)
genus of basidiomycetes decorticates dead at-
tached branches by rupturing the periderm. Ho-
wever, on some of the recorded hosts of D. trian-
gulispora (Salix, Ilex) the presence of Vuilleminia
could not be demonstrated. The fungus appears
to have been overlooked because of its minute
apothecia and its exclusive occurrence on xeric
branches, a habitat which is currently neglected
by collectors. Our collecting activities showed
that such branches carry a vast diversity of little
known ascomycetes.
2 Materials and Methods
2.1 Microscopy
Observations were made with a Zeiss Stan-
dard 14 microscope with 100× oil immersion
phase contrast achromat objective, and a mo-
dified Olympus CH–2 microscope with a Zeiss
100/1.25 oil immersion planachromat objective
and Zeiss Kpl W 16 ×/16 wide field oculars. All
collections were examined in tap water, mostly in
the living state (see Baral 1992), after rehydrating
the branches which were dry when collected. IKI
was added either directly to a water mount, or af-
ter treatment with KOH. The presence of gel was
tested using CRB added to a water mount. CRSDS
was applied to a mount in KOH. Photographic
images (macro- and microphotos) were obtained
using a Nikon Coolpix E4500 and a Canon S70
by using different macrolenses, and all drawings
were done free-hand.
2.2 Cultures and media
Pure cultures were obtained from ascospores
shot on Corn Meal Agar (Sigma-Aldrich, Fluka
analytical #42347). 4g CMA and 12 g Agar-Agar
(Merck #1615) were dissolved in 1l water, which
corresponds to a dilution of 1:4 of the recommen-
ded concentration. The agar plates where incuba-
ted at room temperature. Illumination with UV-A
(365 nm) for some hours was partly applied.
2.3 Deposition of cultures and dried
specimens
Type material is deposited in the public herba-
ria at Botanische Staatssammlung München (M)
and Staatliches Museum für Naturkunde Karlsru-
he (KR), further specimens in the private herba-
ria of the authors (H.B., G.M.). The pure culture
is deposited at Centraalbureau voor Schimmel-
cultures (CBS). A sequence is deposited in Gen-
Bank (JQ688406).
3 Results
Abbreviations: * = living state, † = dead state.
Relative lipid content: 0 = without lipid bodies (=
LBs), 5 = maximum possible lipid content rela-
tive to ascospore volume. Values in { } indicate
the number of collections that were examined. IKI
= Lugol’s solution, ~1% I2, 2% KI, in H2O; KOH
= potassium hydroxide, 5–10%; CRSDS = Congo
Red with SDS (sodium dodecyl sulfate); CRB =
Brilliant Cresyl Blue, ~1% in H2O; KClO = potas-
sium hypochlorite.
Deltopyxis triangulispora Ba r a l &
G. Ma r s o n gen. et sp. nov.
Mycobank: MB 564441, 564489
Diagnosis generico-specifica: Apothecia solita-
ria vel gregaria, 0.07-0.35 mm diam, 60-160 µm
alta, sessilia, brunneoatra, orbicularia, superficia-
lia, margine distincta, leniter crenulata. Asci in sta-
tu vivo 30-50 × 10-13 µm, clavato-fusoidei, apice
late rotundati, tenuitunicati, inamyloidei (IKI), 64-
spori, saepe non stipitati, e uncis nati. Ascosporae
in statu vivo 2.5-4 × 2-3 µm, triangulares, guttulis
oleagineis 1-4 praeditae. Paraphyses rectae, non
ramosae, dense septatae, in statu vivo 1.5-2.8
µm latae, apice clavatae vel capitatae, 2-3.3 µm
latae, cellulae terminales 2.3-7 µm longae, ex-
sudato granulato, intense flavo-brunneo tectae.
Excipulum ectale e textura prismatica-angulare,
10-95 µm altum, cellulae 5-17 × 3-9 µm, angulo
arduo orientatae, multi- ad eguttulatae, gelatina
intercellularis pallide ochracea, extus exsuda-
to crasso, obscure rubrobrunneo vel (olivaceo-)
brunneo tectum, in solutione KOH non dissoluto,
excipulum marginem versus 15-30 µm crassum,
textura prismatica-globulosa. Habitat ad corticem
vel lignum ramulorum durorum siccorum Coryli,
Crataegi, Ilicis, Pruni vel Salicis, in societate vel
supra basidiomata Vuilleminiae et algas.
Holotypus: Luxembourg, Dudelange, Därebësch,
24.XII.1991, in Vuilleminia senescente ad corti-
cem ramuli sicci Crataegi, Guy Marson, holo typus
in M-0190818 (ex H.B. 4576a) isotypus G.M.
4668.
Etymology: named after the triangular, in dorsal
view deltoid ascospores and the resemblance
with the genus Phaeopyxis.
Apothecia rehydrated (0.07-)0.1-0.28(-0.35) mm
diam {8}, 60-160 µm thick {7}, scattered to gregar-
ious, singly or crowded in small groups, sessile or
Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. 177
with an indistinct stipe-like base, superficial, round,
hymenium flat, light cream to dark brownish-grey
or blackish, margin dark brown to black, always
indistinctly to distinctly crenulate-pustulate, hair-
less, protruding (0-)5-20 µm beyond hymenium
{4}, exterior on flanks ± glabrous. Asci *(30-)32-
40(-50) × (8-)9.5-12(-13) µm {6}, † (23-) 35-40(-45)
× (7-)8-10 µm (spores alive) {5}, †24-35(-45) ×
(6.5-)7-10(-11) µm {7} (spores dead), ellipsoid-
clavate-fusoid, 64-spored (50-64 spores counted)
{6}, spores in living mature asci forming a central
column *23-33 × 6.5-9 µm, in dead asci filling the
whole ascus lumen; apex of mature asci broadly
hemisphaerical, rather thin-walled (*0.3-0.4 µm,
†H2O 0.5-0.6 µm), in KOH subapical and upper
lateral wall dictinctly swollen (especially in imma-
ture asci), 0.5-1.4 µm thick {4}, with a ± distinct
apical chamber (here wall 0.3-0.7 µm thick), open-
ing by a large slit-like pore, entirely IKI- {4} (with
or without pretreatment with 5 % KOH), wall sur-
face in CRB faintly to deeply lilac {2}, ectotunica of
apex in KOH+CRSDS partly distinctly reddish; base
± unstalked, rarely stalked, arising from croziers
without perforation {6}; immature living asci with
fusion nucleus 5 µm diam {2}, nucleolus 2.5 µm
diam, asci multinucleate prior to spore delimita-
tion, ascoplasma staining red-brown in IKI only at
the base of some submature asci. Ascospores
slightly to strongly triangular in profile view, medi-
um flattened and ± deltoid to ovoid in dorsal view,
*(2.5-)2.8-3.5(-4) × (2-)2.2-2.8(-3) µm {7}, †2.3-3
× 1.8-2.3 µm {1}, *1.8-2.3 µm wide in dorsal view
(†1.7-1.9 µm); with 1-4 LBs 0.5-1.2 µm diam {4}
(often only near one end, relative lipid content 2-3),
KOH-inert, CRB-; wall surface CRB-, CR-; germi-
nating ascospores rarely seen, budding to form
cylindric(-ellipsoid) phialoconidia *2-3 × 1-1.2
µm {1} with 1-2 small LBs. Paraphyses straight,
consistently unbranched along their entire length,
without anastomoses, laterally emerging from ex-
cipular cells at the junction of hymenium and ectal
excipulum, terminal cells *2.7-6 × (2-)2.5-3 ( -3.3)
µm {4}, †2.3l-7 {2} × (1.3-)1.8-2.7(-3) µm {4} (3-4
µm wide including gel sheath), slightly to distinctly
clavate-capitate, lower cells *(4-)5-9(-10) × (1.5-)
1.7-2.3(-2.7) µm {5}, †(4-)5-6.5(-7.5) × (1-)1.3-1.8
(-2) µm {2}, near base *4-7× 2.2-3.5 µm (†1.6-
2.3 µm wide); 2-4 µm longer than living asci, 4-9
µm longer than dead asci; living cells constricted
at septa, containing a few small LBs, some ter-
minal or lower cells with a very indistinct, tran-
sient, globose body 1-1.2 µm diam; middle part
agglutinated with asci by a gel (CRB bright lilac);
exudate directly attached or over a 0.5-1.5 µm
thick gel, cloddy to granular, pale to deep yellow-
ish- to ochraceous- or olivaceous-brown, 0.2-0.6
up to 1-2 µm thick, unchanged in KOH. Medul-
lary excipulum 5-30 µm thick, of hyaline, dense,
slightly gelatinized, partly horizontally oriented
textura globulosa-angularis-prismatica, cells *2-5
µm wide, multiguttulate to eguttulate, indistinctly
delimited from ectal excipulum. Ectal excipulum
at base and lower flanks of textura (prismatica-)
globulosa-angularis, (10-) 30-95 µm thick {4}, light
brown (subhyaline near base), orientation irregu-
lar or at a 30-90° angle towards surface, individual
cells *(5-)6-12(-17) × (3-)4-7(-9) µm {5}, contain-
ing a few or many larger and smaller hyaline LBs
(0.2-)1-2(-3) µm diam, also ± eguttulate depend-
ing on the population, at mid flanks and margin
15-30 µm thick, of textura prismatica-globulosa ±
irregularly oriented at 10-90°, cells *(2.5-)3-5(-6)
x (2-)2.5-3.5(-4) µm {2}; cells (†) thin-walled but
agglutinated by a medium refractive intercellular
gel */†1-2(-3) µm thick, lower flanks medium gela-
tinized, at mid flanks strongly so, gel in CRB deep
lilac; inner cells at margin forming periphyses-like
outgrowths; intercellular pigment at lower flanks
scattered, light reddish ochre-brown, towards
margin abundant, bright (olivaceous-)yellowish-
ochraceous to red-brown; all parts of ascocarp
inamyloid (IKI); exudate on excipular surface
forming large, 1-2 µm thick, deep red-brown to ol-
ivaceous-brown clods, scattered on flanks, dense
at margin; pigment unchanged in KOH though
sometimes darker, not dissolved (even when
heated), stained blue in CRB, entirely discoloured
in KClO. Anchoring hyphae very sparse, hyaline,
smooth, *1.5-2 µm wide, wall 0.2 µm thick {2}. —
Anamorph: Conidiomata 0.12-0.25(-3.5) mm
diam, round, densely gregarious, partly confluent
and then reaching 0.8 mm diam, sessile, with a
bright ochre- to red-brown peridium composed of
globose, light brown cells; at first globose, black,
apically closed, opening by a transversal slit,
margin indistinctly crenulate, producing a whitish
slimy conidial mass. Conidiophores subglobose
to obpyriform, with a short to long neck, *4.5-8
× (2.5-)3-3.3 µm, conidiogenesis phialidic with
minute collarette. Phialoconidia *(2.7-)3.2-4.5 ×
(1-)1.1-1.4(-1.5) µm, straight to slightly curved,
eguttulate or with a single minute LB.
Ecology: collected in ca. 1-3 m above ground, on
(9-)12-25(-34) mm thick, corticated or partly de-
corticated, dead, internally little to rather strong-
ly white-rotten, attached or sometimes broken
branches of Corylus avellana {1}, Crataegus sp.
178 andrias, 19 (2012)
{6}, C. laevigata {1}, C. monogyna {4}, Ilex aqui-
folium {1}, Prunus spinosa {7}, Salix caprea {1},
Salix ×capreola {1}, Salix (?)cinerea {1}, on little to
mostly medium (sometimes strongly) rotten bark
{3} and wood {4}, often on slightly to very strong-
ly decayed Vuilleminia spp. {16}, V. cystidiata {3},
periderm usually present only on one side of the
branch, ruptured and rolled aside by Vuillemi-
nia which is either still perceptible or has disap-
peared, in the latter case apothecia on exposed
bast, sometimes over narrow cracks of periderm,
or on periderm around spines (Prunus), with ab-
undant green aerophytic algae around and below
apothecia, but often also without. Assoc.: Capro-
nia aff. chlorospora {4}, Catillaria nigroclavata {1},
Chaetosphaeria myriocarpa {1}, Claussenomyces
sp. (on Vuilleminia) {2}, C. atrovirens (conidia ellip-
soid) {1}, C. aff. atrovirens (conidia allantoid) {1},
indet. Corticiaceae {2}, Cryptocoryneum conden-
satum {1}, Dacrymyces sp. {1}, Dactylospora spp.
{13}, Eutypella prunastri {1}, Frullania dilatata {2},
Gloniopsis smilacis {1}, Hyphodiscus aff. hymenio-
philus {3}, Hyphodontia sambuci {1}, Hypnum cu-
pressiforme {3}, Lepraria sp. {4}, Melanelia exas-
peratula {2}, Thyridaria sp. {2}, Metzgeria sp. {1},
?Nitschkia sp. {1}, Orbilia eucalypti {1}, O. vinosa
{1}, Parmelia sulcata {2}, Patellariopsis atrovinosa
{1}, Peniophora sp. {1}, Physcia sp. {2}, Platismatia
glauca {1}, Polydesmia pruinosa {1}, Porina aenea
{2}, Rhizodiscina lignyota {2}, Ulota crispa {1}. Al-
titude: 220–395 m. Geology: mostly ± calcare-
ous: Lower Keuper (Bunte Mergel), Lower Liassic
(Grès de Luxembourg, Marnes et Calcaires de
Strassen), Upper Liassic (minette, Toarcien; Bet-
tembourg bituminous shale), Lower Dogger (coral
limestone). Phenology: throughout the year. De-
siccation tolerance: After 7–10 weeks alive in all
parts; after 17 months still many spores and exci-
pular cells, and some paraphysis cells viable.
Specimens examined (all collected by G. Ma r -
s o n , ø = no specimen preserved):
France, Lorraine, Moselle: 2.8 km SE of Dude-
lange, 1.5 km WNW of Zoufftgen, Nachtweide,
255 m, Crataegus monogyna, on very old Vuil-
leminia, 4.XI.2011 (G.M. 2011.11.04. #01).
Luxembourg: Mersch, 4 km S of Larochette, 2
km E of Fischbach, E of Folkend, Wald, 350 m,
Ilex aquifolium, on wood, 25.IV.1994 (ø); – ibid.,
Ilex aquifolium, on wood and bark, 6.XII.2011
(G.M. 2011.12.06. #01). Luxembourg, 5.5
km NNW of Luxembourg, 1.5 km E of Bridel,
Plakigebierg, 280 m, Prunus spinosa, on Vuille-
minia, 7.III.2003 (H.B. 7316). – 6 km S of Luxem-
bourg, 0.8 km SE of Fentange, Wënkel, 265 m,
Salix caprea, on ?bark, 7.III.1993 (ø). – Capel-
len, 5 km ENE of Pétange, 1 km E of Hautch-
arage, Reischlaedchen, 328 m, Prunus spinosa,
on Vuilleminia cystidiata, 27.III.1999 (ø?). – Gre-
venmacher, 4 km NNE of Grevenmacher, 2 km
NW of Mertert, Schlaufiels, N of Schlammbaach,
220 m, Corylus avellana, on old Vuilleminia,
19.III.1995 (H.B. 5281b). Esch-sur-Alzette, 2.3
km SE of Dudelange, Därebësch, 272 m, Prunus
spinosa, on bark, 12.XII.1991 (H.B. 4571a, G.M.
4643); – ibid., Crataegus sp., on Vuilleminia,
24.XII.1991 (M [ex H.B. 4576a], holotype; G.M.
4668, isotype); – ibid., Prunus spinosa, on bark,
23.II.1992 (G.M. 4786); ibid., ?Crataegus, on
old Vuilleminia, 17.IV.1996 (ø?); ibid., Prunus
spinosa, on Vuilleminia cystidiata, 20.V.2001 (ø);
– ibid., Crataegus laevigata, on old ?Vuilleminia,
28.II.1998 (H.B. 6071a); – ibid., Crataegus sp., on
Vuilleminia, 2.XI.2000 (H.B. 6820a); – ibid., Pru-
nus spinosa and Crataegus sp., on Vuilleminia
cystidiata, also on bark, 30.X.2011 (KR 0029475,
ex H.B. 9634a);ibid., Crataegus, on old Vuille-
minia, 14.I.2012 (ø). – 2.5 km NNE of Dudelange,
1.2 km S of Bettembourg, near railway area, 280
m, Salix (?)cinerea, on wood, 16.X.2000 (H.B.
6808a. – 1.5 km W of Dudelange, Haard, 345 m,
Crataegus monogyna, on Vuilleminia, 30.V.2010
(G.M. 2010.05.30. #01). – 2 km SE of Dudelange,
Bloklapp, 288 m, Prunus spinosa, on old Vuille-
minia,, 19.I.2007 (ø?). – 1.5 km S of Differdange-
Obercorn, Kiemreech, 395 m, Crataegus mono-
gyna, on old Vuilleminia, 6.VIII.2008 (ø). – 1 km
S of Differdange-Obercorn, Kallek, 380 m, Cra-
taegus monogyna, on old Vuilleminia, 16.VI.2010
(H.B. 9626a). 5 km SSW of Luxembourg, 0.7
km N of Kockelscheuer, 305 m, Salix ×capreola,
on wood, 10.XI.2000 (H.B. 6836b). – 1.5 km SW
of Kayl, Léiffrächen, 388 m, Crataegus sp., on
Vuilleminia, 7.X.2011 (H.B. 9625b). – 1 km NW
of Rumelange, Holleschbierg, 380 m, Crataegus,
on old Vuilleminia, partly on apothecia of Dacty-
lospora sp., 6.IV.2010 (ø).
4 Discussion
Based on its peculiar features of triangular spo-
res and multispored asci, Deltopyxis triangulispo-
ra is a well-characterized fungus. In several of its
characteristics, it showed some variation among
the studied populations. However, this variation
was never so strong that we excluded any of our
collections from the description.
Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. 179
Apothecia. The small ascomata of Deltopyxis tri-
angulispora are clearly recognizable only in the
hydrated state. Their size is usually 0.1-0.2 mm
but varies between 0.07-0.15 and 0.2-0.28 mm,
rarely 0.35 mm, sometimes within a collection.
According to the apothecial diameter, the height
of the apothecia varies considerably. The hyme-
nium is usually greyish-cream but especially in
larger or older apothecia it may get dark blackish-
brown due to more abundant exudate over the
paraphyses.
Young (immature) apothecia of D. triangulispora
are blackish and almost globose when rehydra-
ted, with a diameter of 70-80 µm and a height of
60-70 µm. At their apex they possess a 15-20 µm
wide pore. At this development stage no or only
a few very immature asci are present. When the
first asci attain maturity, the hymenium is distinct-
ly exposed and bordered by the protruding dark
margin.
Hamathecium ontogeny. In young apothecia
the paraphyses grow upwards from the bottom
of the young hymenium, but also from the sides
of the hymenial cavity. Those that arise from the
bottom form their short, capitate terminal cell
only when they reach their final length.
During apothecial growth, new paraphyses were
seen to be formed exclusively at the margin. At
the junction of hymenium and ectal excipulum,
new paraphyses emerge laterally from inner cells
of the ectal excipulum (Fig. 1.3). When starting
as lateral outgrowths, they resemble periphyses,
but they soon bend upwards and elongate until
they reach the hymenial surface. At this develop-
ment stage they are still much shorter than the
adult paraphyses, but they will elongate when the
lateral excipulum becomes the bottom of the ex-
panding hymenium.
Young paraphyses in Deltopyxis were never ob-
served to develop between the asci, neither
emerging from the subhymenium, nor by branch-
ing of adult paraphyses. This peculiar feature of
marginal development of new paraphyses might
support the isolated position of Deltopyxis in com-
parison to members of the Helotiales and Orbil-
iomycetes, in which young paraphyses generally
develop also between the asci during apothecial
growth.
Lipid bodies in excipular cells. In the holotype
and some other collections, the cells of the ectal
excipulum contained a more or less high amount
of larger and smaller lipid bodies (LBs, Figs 1.1d,
1.2b, 5c). In some other collections the cells were
often devoid of these droplets or contained them
in lower abundance. We conclude that the lipid
content in the excipular cells is subjected to exter-
nal circumstances rather than having a genetical
origin.
Asci. Based on our observation of living asci at
different stages of development, the ascospores
of Deltopyxis triangulispora are formed by multiple
mitoses after meiosis of the fusion nucleus, i.e.,
the asci are “truly polysporous” in the terminol-
ogy of Ma r t e n s (1937). True polyspory is also ob-
served in the genera Sarea Fr. and Tromeropsis
with similar elongate-saccate, multispored asci
and small ascospores (Ha w k s w o r t H & sH e r w o o d
1981).
The asci are unitunicate and open by a large api-
cal pore which is distinctly slit-like (Fig. 5g images
on the upper right). An apical thickening is only
slightly developed. In very young asci the entire
ascus is thick-walled in the dead state (e.g., when
mounted in KOH, Fig. 5g, images on the left), ex-
cept for a small region at the very apex. Later the
thickened part of the wall is restricted to the apical
region (Fig. 1.1i), though this wall thickening is of-
ten rather inconspicuous, and immature asci may
also be uniformly thin-walled (Fig. 1.1g).
The asci are inamyloid in IKI, with or without KOH
pretreatment. In CRSDS the ectotunica is distinct-
ly stained, but only in the apical region (Fig. 5g,
in another collection the wall did not stain). This
congophily of the apical ectotunica could not be
observed in any of those taxa of Helotiales and
Orbiliomycetes that we have tested so far.
The spores are arranged in a dense elongate
cluster in the living ascus (Figs 1e, 5f, 6c), which
is actively discharged. When rehydrated and
placed in a Petri dish, apothecia started to eject
spore clusters after ca. 5 min. When shot on agar,
the spores form dense, single-layered heaps
which allow quite exact counting of the spores
(Fig. 5h-i). These heaps suggest that the spores
are ejected as one entity, similar as in the Orbil-
iomycetes.
Ascus length was in some specimens consistently
around 25-30 µm but in others always around 30-
40 µm. Likewise, the width of the asci varied be-
tween 7-9 and 10-12 µm. These differences are
only to a certain degree due to real variation, but
mainly depend on the living versus dead state.
However, contrary to many other ascomycetes,
the asci of Deltopyxis shrink only insignificantly
when they loose turgor, as long as the spores re-
main alive. In fact, adding KOH to dead asci that
contain living spores provokes an unexpected as-
cus shrinkage for 10-17 % in length and 5-20 %
180 andrias, 19 (2012)
in width due to shrinkage of the included spores
(a similar effect is induced by shortly heating the
slide). Living asci shrink to a similar rate (10-15 %
in length and 15-20 % in width) when killed by
KOH or heat.
The effect is provoked by an increase in water
content and volume of the living spores as soon
as the ascus turgor is released. In the spore clus-
ter the spores are rather strongly dehydrated.
When the asci loose turgor, the spores fill the
complete ascus by keeping the elastic ascus
wall in a state of tension (Fig. 6d-e). As a conse-
quence, such dead asci are scarcely smaller in
size than living asci (Figs 5f, 6c). This peculiarity
of D. triangulispora might be due to the saccate
shape of the asci which are not much longer than
the pars sporifera.
Despite the observed real variation in ascus size,
the asci appear to be always 64-spored, with rare
exceptions of single asci with perhaps only 32
spores or intermediate spore numbers. The varia-
tion in length is partly explained by the occasional
presence of a more or less pronounced stalk.
The first collection from Folkend near Fischbach
on Ilex consisted of only two apothecia. This spec-
imen differed in the asci which were noted much
shorter (*21 × 9 µm, with a pars sporifera of only
20 × 6 µm). Ascospore size was not evaluated;
also spore number was not noted but might well
have been only 32. This site was revisited in 2011,
but again only a few apothecia could be detected.
Here the asci were distinctly longer (†23-27 × 7.5-
10 µm, containing living spores). They were clearly
more than 32-spored and matched the specimens
on the other hosts in every respect.
Ascospores. The living ascospores are quite con-
sistent in size when measured outside the asci.
Their shape is somewhat variable, but strongly
depends on the direction of view: the character-
istic triangular shape is only seen in profile view,
whereas in dorsal view they look ± deltoid and es-
pecially in oblique view more ellipsoid (Figs 1.1l,
1.2d upper right). Shrinkage of the spores when
killed by KOH lies in the range of 5-20 % in both
length and width.
In turgescent asci the angular spore shape per-
mits a very dense packing within the spore cluster.
This is best seen in asci that lost turgor prior to
spore release: the living spores completely fill the
ascus and fit together like a honeycomb.
Anamorph. In one collection of D. triangulispora
a few ascospores were seen to show yeast-like
germination, i.e. to bud off conidia at one end,
apparently by phialidic conidiogenesis (Fig. 1.4).
This phenomenon seems to be rare because it
was not observed in any of the other collections
studied.
When the ascospores were shot on agar, they
formed dense heaps. Germination did either not
occur at all, or spores germinated only 7 days af-
ter shooting, especially when the heaps were sep-
arated with a glass rod. Often, germinated spores
very soon stopped growing, but in one culture
(on CMA1:4) they formed a very slow-growing
mycelium, with up to 110 µm long hyphae within
ca. 25 days after germination, i.e., ca. 30 µm per
week. When transferred one week later to another
plate, the hyaline mycelium formed a dense mat
that hardly increased in diameter within the next
month. Simultaneously, several dozens of ochre-
to red-brown conidiomata developed (Fig. 6f-g).
These somewhat resemble the ascomata in both
size and shape, but open by a transversal slit.
The abundantly produced phialoconidia resemble
those formed on the ascospores but are longer
and partly also wider.
The conidia of Deltopyxis resemble those obtained
by we B e r (2002) in pure culture of Tromeropsis
microtheca, the ascospores of which produced a
likewise slowly growing mycelium on agar (MEA).
However, the small, ± cylindrical, straight to me-
dium curved conidia of T. microtheca emerged
from little pegs on integrated conidiogenous cells
(conidiogenesis holoblastic). Also larger conidia
were observed which germinated yeast-like to
form small conidia.
Ecology. The sites where Deltopyxis triangulispo-
ra was collected are open woodlands or hedges,
particularly at ± S-exposed slopes but also in ar-
eas with indistinct inclination. The geology was
generally more or less calcareous or basic, and
the vegetation usually thermophilous. The inhab-
ited substrates are dead branches with a usually
initial to optimal, rarely final stage of wood decay,
attached to living or dead shrubs or small trees
one or a few meters above ground, sometimes
also broken but hanging on other branches. Quite
an undisturbed vegetation over many years is a
prerequisite for the detection of many of these
desiccation-tolerant ascomycetes that are con-
fined to xeric branches. Most of the branches on
which D. triangulispora occured were previously
infected by Vuilleminia which was, however, no
more viable when this and other discomycetes
appeared on their basidiomata or on the bark
around. Such branches are usually entirely corti-
cated, but with the periderm replaced by the Vuil-
leminia on one side (Figs. 2c, 3a). The branches
Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. 181
were usually broken only terminally, but are quite
easy to break near the trunk due to an often ad-
vanced wood decay (white rot) caused by Vuil-
leminia. Sometimes they were already broken
towards the trunk and hang on lower branches.
The apothecia of Deltopyxis triangulispora are
preferably found on the very thin layer of the fruit-
bodies of Vuilleminia, either when these were still
whitish to skin-coloured, or on the darker, more
grey-brown to olivaceous marginal regions (Figs.
3a,e, 4b-c). D. triangulispora may also sparsely
occur on bark remote from Vuilleminia, and here
usually over small holes or clefts of the periderm
(Figs. 3b, g, 4d).
In the collections on Salix and Ilex no Vuilleminia
could be noted at all, however. Here the branches
were partly or entirely decorticated, and the apoth-
ecia grew mainly on wood, though often close to
other corticioid basidiomycetes (Peniophora, Hy-
phodontia). Also in a collection on Prunus spinosa
from Därebësch (H.B. 4571a) no Vuilleminia could
be observed, instead, the branch was entirely cor-
ticated.
Frequently, Deltopyxis triangulispora occurs in
close association with species of Dactylospora
and Capronia, which likewise preferably grow on
senescent Vuilleminia. In a single collection, D.
triangulispora even grew partly on the apothecia
of Dactylospora (Fig. 4a). This raises the ques-
tion whether D. triangulispora shows some fun-
gicolous connection to Dactylospora rather than
Vuilleminia.
Aerophytic algae and various lichens and mosses
typically occur on the inhabited branches, but are
not always present. Sometimes they even cover
the apothecia and need to be removed by a jet of
water in order to detect the apothecia.
Relationship. D. triangulispora was first consid-
ered by us to belong in the genus Tromeropsis
(Ascomycota incertae sedis). We studied T. m i -
crotheca ( P. ka r s t .) sH e r w o o d from several col-
lections and found that it differs in many points,
which appears to justify separation at the generic
level (see also the redescription by Ha w k s w o r t H &
sH e r w o o d 1981). T. microtheca resembles D. trian-
gulispora in the dark apothecia and multispored,
inamyloid asci that arise from croziers and open
by a large apical slit. T. microtheca differs in (1)
apothecia with an even margin, (2) an ectal ex-
cipulum of elongate, vertically oriented cortical
cells, (3) paraphyses with uninflated terminal cells
which are much longer than wide, young paraphy-
ses at the margin not formed as in Deltopyxis, (4)
strongly refractive, hyaline, KOH-soluble extracel-
lular drops between the paraphyses in the middle
and lower part of the hymenium, (5) an also later-
ally thickened ascus wall in the apical half of the
mature ascus (dead state), (6) a negative stain of
the entire ascus wall in CRSDS, (7) an often long,
flexuous ascus stalk, (8) 128-spored asci, (9) cy-
lindric-ellipsoid ascospores, and (10) occurrence
on coniferous substrate. Particularly the criteria
1-6 are considered diagnostic at the generic level.
The brief and rather inaccurate description of the
genus Microspora Ve l e n . [non Microspora tH u r e t
1850, algae] with the single species M. dura
Ve l e n ., reported from coniferous wood by Ve l e -
n o V s k ý (1934), resembles Deltopyxis in some re-
spects. However, it was found to be a synonym of
Tromeropsis microtheca, based on a study of syn-
type collections preserved at PRM (Ba r a l ined.).
Several members of Lecanoromycetes show
a certain similarity with Deltopyxis. The genus
Dactylospora ko e r B . resembles not only macro-
scopically, but also in the construction of the ectal
excipulum. It differs in mostly 8-spored asci with
a strong hemiamyloid iodine reaction of the thin
lateral wall and a thick, strongly euamyloid apical
cap, also in brown, septate, elongate ascospores.
The genus Steinia kö r B . resembles Deltopyxis in
its elongate-saccate, 16-spored asci and subglo-
bose ascospores, but the hymenium is hemiamy-
loid, also the asci possess an euamyloid tholus,
the paraphyses are much narrower and some-
what curved, and the apothecia have a convex im-
marginate disc (see ka n t V i l a s & Mcca r t H y 1999).
The lichenized or lichenicolous genus Polysporina
Věz d a resembles Deltopyxis in its multispored asci,
but deviates in richly branched and anastomosing
paraphyses with uninflated apices, and in amyloid
asci (see ka n t V i l a s 1998). Macroscopically, Cat-
illaria nigroclavata (ny l .) sc H u l e r can easily be
confused with Deltopyxis, when the latter forms
larger apothecia.
The resinicolous genus Sarea Fr. closely resem-
bles Deltopyxis in the saccate multispored asci
and the paraphyses tipped by pigmented exu-
date (see also Ha w k s w o r t H & sH e r w o o d 1981).
It differs in asci with a strongly hemiamyloid thick
external gel and an inamyloid tholus with a ros-
trate opening mechanism. The ascus wall layers
are unstained in CRSDS, and the paraphyses are
sometimes branched above and below and are
not formed in the manner as described for Del-
topyxis. The ectal excipulum is internally hyaline,
sharply delimited, heavily gelatinized, of vertically
oriented elongate cells. The pycnidial anamorph
of Sarea is quite similar to that of Deltopyxis.
182 andrias, 19 (2012)
The genus Rhizodiscina Ha F e l l n e r (Patellariales,
Dothideomycetes) is superficially rather similar to
Dactylospora and Deltopyxis. It is characterized
by faintly euamyloid or sometimes inamyloid, sac-
cate, 8-spored asci with a thick inamyloid tholus,
brown, 1-septate ascospores, and projecting,
brown, 3-4.5 µm wide anchoring hyphae.
Quite a lot of genera of Helotiales (Leotiomycetes)
with small, sessile, blackish apothecia bear some
similarity with Deltopyxis. However, the rather
saccate asci in Deltopyxis seem to indicate that
this genus does not belong to the Helotiales. Five
mainly lichenicolous genera with black apothecia
are in the following compared with Deltopyxis:
Geltingia al s t r u p & d. H a w k s w ., Llimoniella Ha-
F e l l n e r & na V .-ro s ., Phaeopyxis ra M B o l d & tr i e -
B e l , Rhymbocarpus zo p F , and Skyttea sH e r w o o d ,
D. Haw k s w . & co p p i n s . Skyttea differs in asci with
strongly thickened apical and thin lateral wall, also
in elongate, hyaline to brown, hair-like cells at
the protruding margin (sH e r w o o d , Ha w k s w o r t H &
co p p i n s 1981). Hair-like structures are partly also
typical of Rhymbocarpus, in which the asci are not
or only slightly thick-walled at the apex. The genus
Llimoniella resembles Deltopyxis in the structure
of the ectal excipulum and the rather thin-walled
asci. It differs in a purplish pigment that turns vi-
olaceous in KOH, and in addition an olivaceous
pigment that turns bright green herein (di e d e r i c H
& et a y o 2000). The type species of Geltingia,
G. associata al s t r u p & d. Ha w k s w ., strongly re-
sembles Deltopyxis in median section and in the
slightly thickened apical ascus wall with a slight
apical chamber, according to the redescription
by di e d e r i c H et al. (2010 Figs 2E, 5). Also Rhym-
bocarpus aggregatus et a y o & di e d e r i c H (2011,
Fig. 1C-E) concurs in median section with Delto-
pyxis. The asci in Phaeopyxis have an immature
overall thickened wall (laterally †1-1.5 µm thick,
apically †1.5-3.5 µm) and partly show a faintly
amyloid iodine reaction; the brown excipular and
hymenial pigment often stains ± violet-brown in
KOH (ra M B o l d & tr i e B e l 1990).
A specimen of Phaeopyxis punctum (Ma s s a l .)
ra M B o l d et al., identified by r. sa n t e s s o n and G.
ra M B o l d (H.B. 4341), was examined by us: the
(bluish) black-brown exudate did not change its
colour in KOH. In contrast to Deltopyxis, the apical
ascus wall did not stain in CRSDS.
All five genera differ from Deltopyxis in their
8-spored, rather narrowly cylindrical asci, in api-
cally not or only slightly inflated paraphyses in
which the terminal cells are generally about 5-10×
longer than wide, in a tendency of the paraphyses
to being branched at the uppermost septum or at
least towards the base, in ellipsoid-ovoid or cylin-
dric-oblong to fusiform ascospores with a usually
rather high lipid content, and in a mostly licheni-
colous habitat, the apothecia being often deeply
immersed or erumpent (except for Llimoniella).
A certain similarity is seen between Deltopyxis
and the type species of Patinella sa c c ., P. h y -
alophaea sa c c ., which was placed with hesitation
by na n n F e l d t (1932) in the Orbiliaceae because of
capitate paraphyses and angular excipular cells,
and later in the Dermateaceae by sp o o n e r (1987).
Reexamination of the type material (Ba r a l ined.)
confirmed placement in the Helotiales, but its re-
lationship to a family is quite difficult to assess.
The apices of the narrow, 8-spored asci have a
pronounced inamyloid apical thickening, and the
strongly capitate, dark brown apices of the long
terminal cells of paraphyses appear as being
thick-walled. The spores have a similar size and
lipid content as in Deltopyxis but are ellipsoid.
The genera Claussenomyces ki r s c H s t . (in the
current circumscription) and Tympanis to d e fre-
quently possess polysporous asci, but this feature
is due to budding of 8 ascospores within the pre-
mature ascus, very different from Deltopyxis. Also
here the asci open by a large apical slit, but the as-
cus wall is congophilous laterally rather than api-
cally [observed in C. kirschsteinianus (ki r s c H s t .)
G. Ma r s o n & Ba r a l and C. atrovirens (pe r s .) ko r F
& aB a w i agg.]. Several further genera with black
apothecia exist in the Helotiales, but none of them
appears to be related to Deltopyxis.
There exist also some undescribed species of
Orbiliomycetes with black-olivaceous apothecia
and 8-16-spored asci (Ba r a l et al. in prep.). Their
ascospores contain spore bodies that disap-
pear when KOH is added, whereas the drops in
the spores of Deltopyxis resist herein and are,
therefore, classified as lipid bodies. Moreover, the
asci have a furcate base without croziers, unlike
Deltopyxis. In its extraordinary spore shape, D.
triangulispora reminds of some undescribed spe-
cies of Orbilia Fr. in which triangular spores actu-
ally occur, but particularly the absence of a spore
body and the fact that small conidia bud from the
ascospores make such relationship highly im-
probable. Like Deltopyxis, the asci of Orbilia open
by an apical slit; yet, it was never the ectotunica
that stained in CRSDS, but instead the endotunica
showed a congophilous reaction in species with a
thick-walled ascus apex.
Phylogenetic placement: a sequence of the ITS1-
5.8S-ITS2 rDNA gained from pure culture (H.B.
Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. 183
9625b) was provided by s. He r M a n t . Two clarify
the phylogenetic placement of Deltopyxis within
the Ascomycota proved impossible with this gene
region, but it allows at least to exclude a closer
relationship with the Orbiliomycetes. This class
is characterized by a signature in the 5.8S rDNA
which was used by sM i t H & Ja F F e e (2009) as one
of three Orbiliales-specific primers (Orb5.8s1F,
see Tab. 1) . Deltopyxis differs from this signature
in three positions, while it concurs in this signature
with many if not all of the remaining Ascomycota
from which a sequence is available in GenBank.
However, it must be mentioned that a few basal
members of Orbiliomycetes, from which we got
sequences, differ from this primer signature at
the last position by a base that corresponds to
the remaining Ascomycota.
Ackowledgements
da G M a r tr i e B e l and pa u l di e d e r i c H are thanked for sug-
gestions concerning related genera, p. d i e d e r i c H for
the identification of some lichens, and p. d i e d e r i c H and
wa l t e r Ga M s for reviewing the manuscript. We are also
thankful to sy lV i e He r M a n t (National Museum of Natural
History, Luxembourg) for gaining a sequence of Delto-
pyxis triangulispora.
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Table 1. Alignment of Orbiliales-specific signature (Orb5.8s1F) in the 5.8S rDNA with the deviating signature of a few
basal Orbiliomycetes and the signature of Deltopyxis and the remaining Ascomycota. Different bases in bold type.
Group 5.8S rDNA
Orbiliomycetes (Orb5.8s1F) G C A G C G A A A C G C G A T A G T
Orbiliomycetes (basal) G C A G C G A A A C G C G A T A G G
Deltopyxis and other Ascomycota G C A G C G A A A T G C G A T A A G
184 andrias, 19 (2012)
Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. Tafel 1
Fig. 1. Deltopyxis triangulispora. 1a)-b) apothecia (rehydrated, a with Capronia aff. chlorospora); 1c), 2a) median sec-
tion of apothecium; 1d) median section of ectal excipulum at apothecial base (cortex); 2b) dto., inner part; 1e) mature
and young ascus (with fusion nucleus), very young ascus in process of crozier formation; 1f), 2c) paraphyses; 1g)-k)
ascus apices (1g) immature, 1h)-j) mature, 1k) emptied); 1l), 2d) ascospores (right spore in 1l) and two upper right
spores in 2d) in dorsal view); 3. median section of margin (excipulum, marginal hymenium); 4a). yeast-like budding of
ascospores; 4b) conidia formed on ascospores. – 1. from Därebësch (Dudelange), on Crataegus, H.B. 4576a (holo-
type), 2. ibid., H.B. 6071a (topotype), 3. ibid., on Prunus spinosa, H.B. 9634a, 4. from Léiffrächen (Kayl), on Crataegus,
H.B. 9625b.
Tafel 2 andrias, 19 (2012)
Fig. 2. Collection sites of Deltopyxis triangulispora. a) Därebësch (Dudelange, type locality), open Crataegus and Prunus spinosa bushes at the border of a pas-
ture; b) Léiffrächen (Kayl), Crataegus bushes in a more dense and air-humid woodland; c) Därebësch, Crataegus branch in situ, with Vuilleminia (14.I.2012).
Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. Tafel 3
Fig. 3. Branches of Crataegus with Deltopyxis triangulispora (rehydrated, white arrows). a)-c), g) from Léiffrächen
(Kayl, H.B. 9625b); d) from Därebësch (Dudelange, H.B. 9634a); e)-f) from Kallek (Obercorn). – a), c) on periderm
over small holes (a) with Vuilleminia below, c) detail of a); d), g) on border of senescent Vuilleminia; e), f) on very
old ?Vuilleminia. – a)-c) with Melanelia exasperatula; g) with Lepraria sp.; b), g) with Dactylospora sp.; f) with Cha-
etosphaeria myriocarpa.
Tafel 4 andrias, 19 (2012)
Fig. 4. Apothecia of Deltopyxis triangulispora on the natural substrate (rehydrated). a) from Holleschbierg (Rumelange); b) from Kiemreech (Obercorn); c) from
Haard (Dudelange); d) from Därebësch (Dudelange, H.B. 9634a); – a)-c) over senescent Vuilleminia (a) on old apothecia of Dactylospora sp.); d) on bark (single
oversized apothecium over split through periderm). – a)-c) Crataegus sp., d) Prunus spinosa
Ba r a l & Ma r s o n : Deltopyxis triangulispora gen. et sp. nov. Tafel 5
Fig. 5. Microscopic teleomorph features of Deltopyxis triangulispora (living state in tap water, except for g) in
KOH+CRSDS). a)-b) median section of apothecium on Vuilleminia; c)-d) dto., cells of ectal excipulum containing LBs;
e. top view on crenulate, dark olivaceous-brown margin; f) turgescent mature asci in context of hymenium; g) as-
cus apices at different stages of development, showing thickened wall in young asci (left), slit-like broad pore after
ejection (upper right), and congophilous ectotunica at apex; h)-i) spore heaps on agar; j)-k) ascospores. – a)-b), i)
Léiffrächen (Kayl, on Crataegus, H.B. 9625b); f) from Kiemreech (Obercorn, on Crataegus monogyna, 6.VIII.2008);
h), k). Därebësch (Dudelange, H.B. 9634a, Prunus spinosa); j) from Holleschbierg (Rumelange).
Tafel 6 andrias, 19 (2012)
Fig. 6. Microscopic teleo- (a-e) and anamorph (f-k) features of Deltopyxis triangulispora (living state in tap water).
a)-b) median section of young apothecia; c-e. mature asci containing living spores (c) ascus turgescent, d)-e) asci
dead); f)-g) anamorph produced in pure culture, conidiomata rupturing by a slit; h) young mycelium from germinated
ascospores; i) mycelium around conidiomata; j) globose cells of peridium; k) phialides and phialoconidia. – a)-c)
Därebësch (Dudelange, H.B. 9634a, Prunus spinosa); d)-e) Wald (Koedange, on Ilex, 25.XII.2011); f)-k). Léiffrächen
(Kayl, on Crataegus, H.B. 9625b).
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