Three new species of Neohelicomyces (Tubeufiales, Tubeufiaceae) from freshwater and terrestrial habitats in ChinaAuthorMa, Jianhttps://orcid.org/0009-0008-1291-640XSchool of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang 550003, China & Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, ThailandAuthorGomdola, Deecksha0000-0002-0817-1555Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, ThailandAuthorBoonmee, Saranyaphat0000-0001-5202-2955Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, ThailandAuthorShen, Hong-Wei0000-0003-2508-1970Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand & School of Science, Mae Fah Luang University, Chiang Rai, 57100, ThailandAuthorTang, Xia0000-0003-2705-604XCenter of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand & College of Agriculture and Biological Science, Dali University, Dali, ChinaAuthorZhang, Li-Juan0000-0002-3234-6757School of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang 550003, China & Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, ThailandAuthorLu, Yong-Zhong0000-0002-1033-5782School of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang 550003, ChinaAuthorHyde, Kevin D.0000-0002-2191-0762Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand & Engineering and Research Center for Southwest Bio-Pharmaceutical Resources of National Education Ministry of China, Guizhou University, Guiyang 550025, China & Innovative Institute for Plant Health / Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China, Ministry of Agriculture and Rural Affairs, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, Guangdong, China & Department of Botany and Microbiology, College of Science, King Saud University, Saudi ArabiatextMycoKeys20242024-06-03105317336journal article29806810.3897/mycokeys.105.124129edc0c518-b02b-4848-88d3-deee54448cb7Neohelicomyces guizhouensis
J. Ma, Y. Z. Lu & K. D. Hyde
sp. nov.Fig. 2Etymology.
The epithet “
guizhouensis
” refers to
Guizhou Province
, from where the specimen was collected.
Holotype
.
HKAS
134924
.
Description.Saprobic
on decaying wood in a freshwater habitat.
Sexual morph
Unknown from natural habitat.
Asexual morph
Hyphomycetous, helicosporous.
Colonies
on natural substrate superficial, effuse, gregarious, white to light pink.
Mycelium
semi-immersed, hyaline to pale brown, septate, branched hyphae, smooth, comprising glistening conidial mass.
Conidiophores
78–288 μm long, 4–6 μm wide (x ¯ = 179.5 × 5 μm, n = 20), macronematous, mononematous, erect, flexuous, cylindrical, sometimes branched, septate, hyaline to pale brown, smooth, thick-walled.
Conidiogenous cells
9–18 μm long, 2.5–4.5 μm wide (x ¯ = 14 × 3.5 μm, n = 25), holoblastic, mono- to poly-blastic, integrated, sympodial, intercalary or terminal, cylindrical, with a denticulate protrusion, truncate at apex after conidial secession, hyaline to pale brown, smooth-walled.
Conidia
solitary, acropleurogenous, helicoid, rounded at the tips, 18–21.5 μm in diameter and conidial filament 2–2.7 μm wide (x ¯ = 20 × 2.3 μm, n = 20), 94.5–148.5 μm long (x ¯ = 126.5 μm, n = 30), multi-septate, coiled 2 ¾ – 3 ½ times, becoming loosely coiled in water, guttulate, hyaline, smooth-walled.
Culture characteristics.
Conidia producing germ tubes on
PDA
within 9 hours of incubation at 25 ° C. Colonies on
PDA
are circular with flat surface and undulate edge, reaching
40 mm
diameter after 45 days of incubation at 25 ° C, top view of colony pale pink to brown, reverse brown to dark brown.
Neohelicomyces guizhouensis
(
HKAS
134924
, holotype)
a, b
colonies on the host surface
c, d
conidiophores, conidiogenous cells and conidia
e – g
conidiogenous cells
h – l
conidia
m
germinated conidium
n, o
surface and reverse colonies on
PDA
after 45 days of incubation at 25 ° C. Scale bars: 50 μm (
c
); 30 μm (
d
); 10 μm (
e, g, m
); 5 μm (
f, h – l
).
Material examined.China
,
Guizhou Province
, Zunyi City, Renhuai City, Daba Town, on decaying wood in a freshwater habitat,
17 August 2021
, Jian Ma, RH 4 (
HKAS
134924
,
holotype
;
GZAAS
23–0619
,
isotype
), ex-type living cultures
GZCC
23–0725
;
Ibid
., RH 4.1 (
GZAAS
23–0620
,
paratype
), living culture
GZCC
23–0726
.
Notes.
The newly-identified strains (
GZCC
23–0725
and
GZCC
23–0726
) are phylogenetically grouped with
N. denticulatus
,
N. deschampsiae
,
N. pallidus
and
N. pandanicola
(Fig.
1
). However, it is most closely related to
N. deschampsiae
(
CPC
33686) phylogenetically and a comparison of polymorphic nucleotides across
ITS
and
LSU
sequences between
GZCC
23–0725
and
N. deschampsiae
(
CPC
33686) revealed nucleotide base disparities of 34 / 546 bp (6.3 %, including fourteen gaps) and 4 / 860 bp (0.5 %, including 0 gap), respectively. Morphologically,
N. guizhouensis
is most similar to
N. dehongensis
in having macronematous, mononematous, erect, flexuous branched conidiophores and solitary, helicoid, hyaline conidia (
Dong et al. 2020
). However,
N. dehongensis
can be delineated from
N. guizhouensis
by its longer conidia (145–210 μm vs. 94.5–148.5 μm) and wider conidial filaments (20–25 μm vs. 18–21.5 μm) (
Dong et al. 2020
). Therefore, based on the findings from both molecular and morphological evidence, we propose
N. guizhouensis
as a new species.