Septonema lohmanii G. Delgado & O. Koukol, sp. nov., a new species in Mytilinidiales (Dothideomycetes) and the phylogenetic position of S. fasciculare (Corda) S. Hughes
Author
Delgado, Gregorio
EMLab P & K Houston, 10900 Brittmoore Park Drive Suite G, Houston, TX 77041 (United States) and Department of Mycology, Institute of Ecology, Evolution and Diversity, Goethe Universität Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt am Main (Germany) gdelgado @ emlabpk. com (corresponding author)
Author
Koukol, Ondřej
Department of Botany, Faculty of Science, Charles University, Benátská 2, CZ- 128 01 Praha 2 (Czech Republic)
Author
Miller, Andrew N.
Illinois Natural History Survey, University of Illinois, 1816 South Oak Street, Champaign, IL 61820 (United States)
Author
Piepenbring, Meike
Department of Mycology, Institute of Ecology, Evolution and Diversity, Goethe Universität Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt am Main (Germany)
text
Cryptogamie, Mycologie
2019
2019-03-13
20
2
3
21
journal article
244479
10.5252/cryptogamie-mycologie2019v40a2
e80dd547-3693-49a9-a1a7-d53d70b88481
1776-100X
7825465
Septonema fasciculare
(Corda) S. Hughes
(
Figs 5
,
6
)
In Canadian Journal of Botany
36: 803 (1958)
.
MATERIAL EXAMINED. —
Belgium
.
Haasrode, Meerdaalwoud, on the outer side of bark of
Pinus sylvestris
L
.,
16.
V
.1966
, coll.
G
.
L
. Hennebert, isol.
G
.
L
. Hennebert (
MUCL
[
MUCL
8886], deposited as
Septonema secedens
).
Canada
.
Quebec province
, Gatineau Parkway, near Pink Lake, on bark of Coniferae,
X.1959
, coll.
W
.
B
. Kendrick, det.
W
.
B
. Kendrick (
IMI
[
IMI
84944a]). —
Septonema secedens
Corda
, Great Britain, Surrey County, Ashtead Common, on bark of
Betula
sp.
,
12.
I
.1947
, coll.
S
.
J
. Hughes, det.
S
.
J
. Hughes (
IMI
[
IMI
9939]);
ibid
., Oxshott, on periderm of
Betula
sp.
,
7.III.1948
(
IMI
[
IMI
25538a]).
DESCRIPTION
Colonies
on natural substrate effuse, hairy or cottony, black.
Mycelium
partly superficial, partly immersed composed of branched, septate, smooth, brown hyphae, 1.5-2 µm wide.
Conidiophores
macronematous, monomenatous, erect, simple, straight or flexuous, sometimes bent at a 90° angle or rarely bifurcating, cylindrical, septate, smooth, brown, sometimes paler distally and constricted at the septa delimiting terminal or subterminal cells, up to 480 µm long, 3-4 µm wide, 5-9 µm wide at the base.
Conidiogenous cells
monoblastic or polyblastic, integrated, terminal or intercalary, occasionally intercalary-pleurogenous, determinate, cylindrical, subcylindrical or somewhat clavate at the tip, pale brown, brown or grayish brown, 0-1(-4) septate, sometimes constricted at the basal delimiting septa, 17-28 × 3-5(-6) µm, with 1-2 truncate or subdenticulate, neither thickened nor darkened apical conidiogenous loci giving rise to ramoconidia.
Ramoconidia
cylindrical to narrowly clavate, sometimes fusoid-ellipsoid, 0-1(-3)-septate, thick-walled, smooth, pale brown to brown or dark grayish brown, in chains of up to 3, 15-21(-25) × 3-5 µm, with 1-2 truncate or subdenticulate apical conidiogenous loci;
conidia
cylindrical, sometimes slightly attenuated in their central part, pale grayish brown to grayish brown, 1-4-septate, mostly 3, rarely up to 7 septa, thin-walled, smooth, with rounded ends, (11-)13-22(-30) × 4-5 µm, in simple or rarely branched acropetal chains of up to 9 conidia.
Colonies
on MEA restricted, very slow growing, reaching
4-5 mm
diam. after 1 month at room temperature (22-25° C), circular, black, velvety, convex, raised
1-2 mm
, sometimes with a slight amount of dark gray aerial mycelium in the center, margin entire, reverse black, sporulation not observed after four months.
NOTES
The strain MUCL 8886 did not sporulate on any of the culture media used including nutrient poor water agar with sterile wooden toothpicks. Morphological examination of the herbarium specimen source of this strain showed that it is conspecific with
S. fasciculare
and not with
S. secedens
. The specimen closely matches previous descriptions of
S. fasciculare
(
Ellis 1976
; Holubovà-Jechovà 1978) in forming black, hairy to cottony colonies on bark of
Pinus
species
, particularly
P. sylvestris
, and having simple conidiophores up to 880 µm long, cylindrical, grayish brown to brown, mostly 3- but also 1-, 2- or 4-septate conidia with rounded ends, 14-20 µm long, consistently 4-5 µm wide and produced in branched, acropetal chains (
Fig. 6
B-J). Further evidence of conspecificity was found by comparing MUCL 8886 with specimen IMI 84944a belonging to
S. fasciculare
.
Septonema secedens
, on the other hand, differs from
S. fasciculare
by forming olivaceous brown to dark brown, velvety colonies on natural substrate, shorter, branched conidiophores up to 200 µm long and pale brown to brown, wider conidia 5-7 µm wide, with truncate ends (
Fig. 6
K-N). A comparison between MUCL 8886 and
two specimens
of
S. secedens
deposited in IMI (9939 and 25538a) confirmed that they belong to different taxa. Dried cultures found inside the herbarium packet of MUCL 8886 and grown on MA (Malt Agar) or MEA according to their labels were sterile as well.