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Ci a ion: Ba os, J.; Seena, S. Fungi in
F eshwa e s: P io i ising Aqua ic
Hyphomyce es in Conse a ion
Goals. Wa e 2022,14, 605.
h ps://doi.o g/10.3390/w14040605
Academic Edi o : Jun Yang
Recei ed: 30 Decembe 2021
Accep ed: 15 Feb ua y 2022
Published: 16 Feb ua y 2022
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wa e
Re iew
Fungi in F eshwa e s: P io i ising Aqua ic Hyphomyce es in
Conse a ion Goals
Juliana Ba os and Sahade an Seena *
MARE-Ma ine and En i onmen al Sciences Cen e, Depa men o Li e Sciences, Uni e si y o Coimb a,
3004-517 Coimb a, Po ugal; [email p o ec ed]
*Co espondence: [email p o ec ed] o [email p o ec ed]
Abs ac :
Dep i a ion o p o ec ion o aqua ic hyphomyce es is dis u bing because hey a e key
playe s in eshwa e ecosys ems ac oss he globe. To a ain a mo e holis ic conse a ion pa adigm o
biodi e si y in eshwa e s, i is necessa y o b oaden ou ecological pe cep ion o mic o ungi, mainly
in aqua ic hyphomyce es. A conside able g oundwo k s ill needs o be accomplished in p og essing
owa ds conse ing aqua ic hyphomyce es. O e coming he pauci y o in o ma ion ega ding he
a e and endange ed species, biogeog aphy and abo e all, a global biodi e si y da abase, would
be a signi ican con ibu ion in he ini ia ion o an o e a ching conse a ion s a egy o aqua ic
hyphomyce es. Being awa e ha he biodi e si y decline in eshwa e s is ala ming, he e we seek
o explo e why biodi e si y da a o aqua ic hyphomyce es a e missing. This a icle closely exam-
ines he h ea s o he biodi e si y o aqua ic hyphomyce es and eshwa e ecosys ems. Mo ing
o wa d, we ad oca e a s uc u ed app oach o gaining a ho ough unde s anding o emb ace aqua ic
hyphomyce es biodi e si y in o he conse a ion s a egies. Including aqua ic hyphomyce es in
he conse a ion objec i es may a ac mo e unding oppo uni ies o global su eys o ini ia e a
ungal inclusi e conse a ion e a. Fungal conse a ion en u es can p o i om in e disciplina y
collabo a ions and cu ing-edge science and echnology, leading o in o med decision making o
biodi e si y assessmen and managemen .
Keywo ds: mic o ungi; biodi e si y; IUCN; CBD; conse a ion s a egies; mac o ungi
1. In oduc ion
F eshwa e s comp ise less han 3% o he o al wa e on ea h [
1
,
2
] and a e home o
mo e han 100,000 desc ibed species. Ba ely 0.006% o he eshwa e s a e i e s [
3
] and
s eams cons i u e 80% o hei ne wo ks [
1
,
3
]. F eshwa e is i al o sus aining li e on
ea h and p o iding c ucial bene i s o ou su i al and well-being (e.g., d inkable wa e ,
ag icul u e, powe gene a ion, sani a ion and ec ea ion) [
4
]. The e e -inc easing demand
o eshwa e s makes hem pa icula ly ulne able and consequen ly he mos endange ed
ecosys ems on he plane . The e o e, he e is a g owing need o s ike a balance be ween
ul illing ou basic needs and he conse a ion o aqua ic ecosys ems [
5
]. To da e, billions
o people a ound he globe ha e been and a e s ill dep i ed o sa e d inking wa e [
6
].
In addi ion, he ecen co ona i us pandemic since 2019 emphasised an u gen need o
adequa e solu ions o mee mode n socie y’s wa e needs while main aining and p o ec ing
eshwa e ecosys ems’ s uc u e, unc ioning and biodi e si y.
Biodi e si y is undamen al o human well-being and heal h [
7
]; ne e heless, bio-
di e si y loss is occu ing a unp eceden ed le els. Ala mingly, 83% o he desc ibed
wo ld eshwa e species and 30% o eshwa e ecosys ems ha e anished since 1970 [
8
].
Howe e , we ha e jus begun o add ess he eshwa e biodi e si y conce ns and ecog-
nise i as a p io i y o conse a ion s a egies since he ea ly 2000s [
5
,
9
–
11
]. Cu en ly,
a ound one- hi d o he eshwa e biodi e si y is a isk o ex inc ion, owing o an h o-
pogenic dis u bances, such as o e -exploi a ion [
2
], habi a loss [
12
], pollu ion discha ge [
5
],
Wa e 2022,14, 605. h ps://doi.o g/10.3390/w14040605 h ps://www.mdpi.com/jou nal/wa e
Wa e 2022,14, 605 2 o 16
and in oduc ion o exo ic species [
13
]. Mo eo e , he ex inc ion o species is expec ed o
exace ba e wi h he e e -inc easing popula ion and he ongoing clima e change [6].
Fungi o m a majo sha e o global biodi e si y; bo h mac o ungi and mic o ungi
cons i u e a ound 10 o 20% o he o al species [
14
]. Gene ally, eshwa e ungi a e
mic oscopic and do no bea any isible ui ing bodies [
15
]. Aqua ic hyphomyce es
(Ingoldian ungi, eshwa e hyphomyce es o amphibious ungi) a e a phylogene ically
he e ogeneous g oup o anamo phic mic o ungi abound in well-oxygena ed eshwa e s.
They commonly occu on he decaying o ganic ma e and elease copious quan i ies o
asexual spo es (conidia) in o he lo ic habi a s [
16
]. These spo es a e mainly e a adia e o
sigmoid in shape (Figu e 1).
Wa e 2022, 13, x FOR PEER REVIEW 2 o 15
dis u bances, such as o e -exploi a ion [2], habi a loss [12], pollu ion discha ge [5], and
in oduc ion o exo ic species [13]. Mo eo e , he ex inc ion o species is expec ed o exac-
e ba e wi h he e e -inc easing popula ion and he ongoing clima e change [6].
Fungi o m a majo sha e o global biodi e si y; bo h mac o ungi and mic o ungi
cons i u e a ound 10 o 20% o he o al species [14]. Gene ally, eshwa e ungi a e mi-
c oscopic and do no bea any isible ui ing bodies [15]. Aqua ic hyphomyce es (Ingold-
ian ungi, eshwa e hyphomyce es o amphibious ungi) a e a phylogene ically he e o-
geneous g oup o anamo phic mic o ungi abound in well-oxygena ed eshwa e s. They
commonly occu on he decaying o ganic ma e and elease copious quan i ies o asexual
spo es (conidia) in o he lo ic habi a s [16]. These spo es a e mainly e a adia e o sigmoid
in shape (Figu e 1).
Figu e 1. Spo es ( ep oduc i e s uc u es) o aqua ic hyphomyce es, (a) Heliscella s ella a, (b) Te -
achae um elegans, (c) Neonec ia lugdunensis, (d) Dend ospo a e ec a, (e) Cla a iopsis aqua ica and ( )
A iculospo a e acladia.
Aqua ic hyphomyce es we e acciden ally disco e ed in 1942 by Ingold while looking
o chy ids [16]. They we e g ea ly igno ed un il he limnologis s ealised he signi ican
con ibu ion o alloch honous o ganic ma e ials o s eam ood webs [17]. Aqua ic hypho-
myce es play a pa amoun ole in he decomposi ion o de i us h ough hei enzyma ic
ac i i ies, consequen ly enhancing he pala abili y and nu i ional quali y o he li e o
he in e eb a es [18]. This ac i i y acili a es he ans e o ene gy and nu ien s o highe
ophic le els [18,19]. Wi h he ad ancemen in axonomic esea ch, 335 mo phospecies
o aqua ic hyphomyce es ha e been iden i ied ( o e iew, see Dua e e al. [20]), belong-
ing mainly o Ascomyco a wi h a small pe cen age a ibu ed o Basidiomyco a [21]. By
he 2000s, g owing e idence sugges ed ha he aqua ic hyphomyce es species ichness o
iden i y migh in luence he eshwa e ecosys em p ocesses [22,23]. This undamen al as-
pec es o ed he in e es in he po en ial connec ion be ween aqua ic hyphomyce es’ bio-
di e si y and eshwa e ecosys em p ocesses, heal h and in eg i y [23–27]. The ongoing
global changes and an h opogenic impac s on he eshwa e s ha e encou aged mo e in-
sigh s in o hei biodi e si y changes and occu ence in he li le-explo ed egions ac oss
he globe [20].
E en hough aqua ic hyphomyce es a e he co ne s one o he eshwa e ecosys-
ems’ unc ional in eg i y and heal h [28], hei conse a ion s a us is obscu e. I is o u -
mos impo ance o sys ema ically analyse hei cu en s a us and u u e i conse a ion
measu es a e o be adminis e ed. This app oach will help o unde s and he knowledge
gap and implemen esea ch in o adequa e managemen p ac ices. Mo eo e , applying
cu ing-edge molecula echniques o iden i y aqua ic hyphomyce es species and he abil-
i y o e alua e he en i e ungal communi ies will enable esea che s o de e mine and
Figu e 1.
Spo es ( ep oduc i e s uc u es) o aqua ic hyphomyce es, (
a
)Heliscella s ella a, (
b
)Te a-
chae um elegans, (
c
)Neonec ia lugdunensis, (
d
)Dend ospo a e ec a, (
e
)Cla a iopsis aqua ica and (
)A ic-
ulospo a e acladia.
Aqua ic hyphomyce es we e acciden ally disco e ed in 1942 by Ingold while looking
o chy ids [
16
]. They we e g ea ly igno ed un il he limnologis s ealised he signi i-
can con ibu ion o alloch honous o ganic ma e ials o s eam ood webs [
17
]. Aqua ic
hyphomyce es play a pa amoun ole in he decomposi ion o de i us h ough hei enzy-
ma ic ac i i ies, consequen ly enhancing he pala abili y and nu i ional quali y o he li e
o he in e eb a es [
18
]. This ac i i y acili a es he ans e o ene gy and nu ien s o
highe ophic le els [
18
,
19
]. Wi h he ad ancemen in axonomic esea ch, 335 mo phos-
pecies o aqua ic hyphomyce es ha e been iden i ied ( o e iew, see Dua e e al. [
20
]),
belonging mainly o Ascomyco a wi h a small pe cen age a ibu ed o Basidiomyco a [
21
].
By he 2000s, g owing e idence sugges ed ha he aqua ic hyphomyce es species ichness
o iden i y migh in luence he eshwa e ecosys em p ocesses [
22
,
23
]. This undamen al
aspec es o ed he in e es in he po en ial connec ion be ween aqua ic hyphomyce es’
biodi e si y and eshwa e ecosys em p ocesses, heal h and in eg i y [
23
–
27
]. The ongoing
global changes and an h opogenic impac s on he eshwa e s ha e encou aged mo e
insigh s in o hei biodi e si y changes and occu ence in he li le-explo ed egions ac oss
he globe [20].
E en hough aqua ic hyphomyce es a e he co ne s one o he eshwa e ecosys ems’
unc ional in eg i y and heal h [
28
], hei conse a ion s a us is obscu e. I is o u mos
impo ance o sys ema ically analyse hei cu en s a us and u u e i conse a ion mea-
su es a e o be adminis e ed. This app oach will help o unde s and he knowledge gap
and implemen esea ch in o adequa e managemen p ac ices. Mo eo e , applying cu ing-
edge molecula echniques o iden i y aqua ic hyphomyce es species and he abili y o
Wa e 2022,14, 605 3 o 16
e alua e he en i e ungal communi ies will enable esea che s o de e mine and es ablish
he ends in biodi e si y and gene ic pa e ns. These mode n echniques, which a ou
species de ec ion in he absence o ep oduc i e s uc u es, may open new a enues o
ungal conse a ion.
The Con en ion on Biological Di e si y (CBD) is he i s global ag eemen o em-
b ace all ace s o biological di e si y. The CBD a ge s inco po a ing all g oups o o -
ganisms and conse ing hei biodi e si y. They designa ed 2010 as he In e na ional
Yea o Biodi e si y, bu hei logo demons a ed jus plan s and animals and in hei
o icial p omo ional ideo, ungi we e no e en men ioned. Howe e , he conse a ion
o mac o ungi became global in 2019 and he mac o ungal ed lis escala ed om 66 o
280 (h p://iucn.ekoo.se/iucn/plans/; accessed on 28 Decembe 2021). The In e na ional
Union o Conse a ion o Na u e’s (IUCN) e o s o assess ungi is an icipa ed o ocus
on mac o ungi (Ascomyce es and Basidiomyce es) in he u u e. Mic o ungi, including
aqua ic hyphomyce es, a e o phaned in he Rio con en ions, al hough many species may
be endemic o e en endange ed. The global Red Lis ini ia i e’s g oss ma ginalisa ion o
hese ungi impedes hei inclusion in conse a ion discussions and mee ings, unding
ini ia i es, policy decision making and mos impo an ly, conse a ion ac ions. Pa icula ly
wi h inc easing knowledge on he ole o aqua ic hyphomyce es in eshwa e s, aising
awa eness ega ding hei ecological impo ance and he necessi y o conse e hem is
becoming inc easingly mo e pi o al. Ad ancing he conse a ion ision o aqua ic hy-
phomyce es can only be achie ed by enhancing he coo dina ion among he limnologis s,
mycologis s and he b oade conse a ion communi ies o os e s a egies. He e, we i s
iden i y he h ea s o eshwa e ecosys ems and biodi e si y o aqua ic hyphomyce es.
The impac o h ea s, such as hyd ological al e a ions, ag icul u al ac i i ies, in asi e
species, clima e changes and o he majo pollu an s on aqua ic hyphomyce es, is discussed.
Second, we call a en ion o he ac ha adequa e knowledge on he biodi e si y o aqua ic
hyphomyce es is missing, al hough he biodi e si y decline in eshwa e s is ala ming.
Thi d, we ecommend a esponsible app oach owa ds unde s anding he biodi e si y o all
ungi, including aqua ic hyphomyce es and emb acing hem in biodi e si y conse a ion
s a egies. This app oach will bene i scien is s, mainly limnologis s, mycologis s, conse a-
ionis s and a b oade public, namely, policymake s, go e nmen al and non-go e nmen al
o ganisa ions, o he s akeholde s and socie y.
2. Th ea s o F eshwa e Ecosys ems and Biodi e si y o Aqua ic Hyphomyce es
Globally o e he pas 100 yea s, eshwa e demand has inc eased six- old [
29
]. I is
p edic ed ha by 2030, wa e equi emen s may exceed 50% o i s p o isioning capaci y [
30
].
E o s ha e been mainly di ec ed o ‘ensu e wa e a ailabili y o all’ (Sus ainable De elop-
men Goal 6), o en neglec ing biodi e si y and ecosys em unc ioning o eshwa e s. Mos
o he enginee ed solu ions culmina e in addi ional p essu es on he ecosys em and signi i-
can changes in he global wa e cycle [
31
]. This exace ba ed wa e necessi y by mode n
human socie y may be p ima ily a ibu ed o he combina ion o economic de elopmen ,
popula ion g ow h and al e a ions in consump ion pa e ns. The en i onmen al changes
due o hese h ea s, such as modi ica ions in pH, ca bon and ni ogen cycles, empe a u e,
low and uno pa e ns [
5
], modula es he biodi e si y o he impac ed a ea, p omo ing
shi s in species dominance and, mos impo an ly, a decline in biodi e si y.
I is a signi ican challenge among limnologis s o de e mine how he en i onmen al
ac o s, including hei o e laps, a ec he ela ionship be ween biodi e si y and ecosys em
unc ioning [
32
]. Globally, aqua ic hyphomyce es a e common o as - lowing unpollu ed
eshwa e s [
33
]; hey a e sensi i e o a ious en i onmen al s esses al e ing hei di e si y,
ac i i y and communi y composi ion, comp omising de i al ood webs [
34
]. Howe e ,
aqua ic hyphomyce es a e also e idenced o cope wi h a wide ange o en i onmen al
s ess, such as pollu ion o d ough [
33
]. Thus, hey a e p oposed as sensi i e indica o s
o en i onmen al changes and o isk assessmen s udies [
35
]. Howe e , i is no e iden
whe he he en i onmen al s esso s lead o he ex inc ion o aqua ic hyphomyce es species.
Wa e 2022,14, 605 4 o 16
Apa om he undeniable o e -exploi a ion [
2
] o eshwa e s, o he an h opogenic
ac o s esponsible o he deg ada ion o eshwa e ecosys ems and biodi e si y o aqua ic
hyphomyce es a e hyd ological al e a ions, ag icul u al p ac ices, in asi e species, clima e
change and o he pollu an s [2].
2.1. Hyd ological Al e a ions
O e he las cen u y, i e s and s eams ha e been hea ily modi ied o human de el-
opmen al pu poses [
36
], esul ing in an al e ed global wa e cycle. Hyd ological al e a ions
a e he main abio ic ac o go e ning eshwa e ecosys ems’ s uc u e, unc ioning and
in eg i y [
37
]. I also de e mines he ex en , dep h and low eloci y o eshwa e s, and
consequen ly, he anspo o nu ien s and sedimen s. To da e, ba ely 37% o i e s longe
han 1000 km emain ee- lowing h oughou hei en i e leng h [
10
]. Dams ha e been con-
s uc ed on mos o he majo i e s in he wo ld [
38
], playing a pi o al ole in modi ying
hei low and inunda ion pa e ns; o ins ance, Colo ado, Ganges and Yellow Ri e s ha e
hei lows hea ily comp omised by he cons uc ion o a la ge numbe o dams [
5
]. Dams
also p omo e d ough due o he di e sion o wa e in he i e s [
39
]. Such modi ica ions
lead o al e a ions in habi a condi ions and mig a ion o species and ma e cycling, such
as ca bon and nu ien s [
40
]. No ably, damming o i e s egula es he biodi e si y o
aqua ic hyphomyce es and hei ecological p ocesses [
41
]. A s udy conduc ed in 17 s eams
impac ed by he p esence o dams demons a ed ha decomposi ion o o ganic ma e
dec eased downs eam due o al e a ions in he na u al low egime o s eams. This could
be a ibu ed o he al e a ions in nu ien and ca bon low along he wa e cou se [42].
2.2. Ag icul u al P ac ices
Ri e s and s eams a e p o oundly linked o hei su ounding e es ial ecosys-
ems [
19
,
43
,
44
], owing o su ace uno and elemen al cycling; hence, any ac i i y ha
modi ies e es ial s uc u e and composi ion will consequen ly impac eshwa e ecosys-
ems. Annually, a ound 70% o he a ailable su ace wa e is used only o sus ain ag i-
cul u al p ac ices [
45
]. Ag icul u e also p omo es he eplacemen o na u al ege a ion,
he eby changing he i e ine canopy, inpu s o alloch honous o ganic ma e , shading
and wa e empe a u e, modi ying he ecosys em s uc u e and unc ioning. In addi ion,
su ace uno om ag icul u al land may ca y chemicals and e ilise s con aining high
le els o nu ien s [
5
]. High nu ien loads alone o when accompanied by o he en i-
onmen al ac o s, such as empe a u e [
46
], a e able o s imula e he g ow h o aqua ic
hyphomyce es [
34
,
47
,
48
]. The ew a ailable s udies on he impac s o high nu ien loads
on he aqua ic hyphomyce es demons a e ha hei esponse di e s be ween species [
49
].
Besides nu ien s, ag icul u e uno ca ies la ge quan i ies o ag ochemicals, such as
pes icides [
50
], ungicides [
50
] and sal s [
51
], wi h po en ial impac s on he biodi e si y o
aqua ic hyphomyce es [
52
]. In gene al, he esponse o aqua ic hyphomyce es o ag ochem-
icals is species-speci ic and g ea ly depends on hei chemical p ope ies. A clea di e ence
be ween he esponse o species o concen a ions and ypes (he bicides and ungicides)
has been obse ed when aqua ic hyphomyce e species we e exposed o he bicides and
ungicides in a p e ious s udy [50].
2.3. In asi e Species
Human ac i i ies ha e been des oying geog aphical ba ie s wo ldwide [
53
]; conse-
quen ly, he bounda ies be ween na i e and non-na i e species a e likely o become blu ed.
The in asi e ipa ian species may modi y he habi a condi ions, esul ing in compe i ion
o esou ces and space. The eplacemen o ipa ian na i e ege a ion by in asi e species
may impac he di e si y o aqua ic hyphomyce es and eshwa e ecosys em unc ion-
ing [
54
,
55
]. Fo ins ance, he ichness o he aqua ic hyphomyce es species was highe
in he e e ence s eam han in he s eam su ounded by he in asi e (Acacia) species
a ec ing he lea li e decomposi ion [
56
]. Exo ic species may also con ibu e o ecosys-
em biodi e si y by in e ac ing o ac ing as unc ional homologs, sus aining impo an
Wa e 2022,14, 605 5 o 16
ecosys em se ices [
57
]. Howe e , in mos cases, when in asi e species h i e, i causes
as dispa i ies owing o he lack o p eda o s, exploding hei popula ion a he expense o
na i e species [
58
]. In addi ion, edis ibu ion o na i e eshwa e species is in luenced by
global clima e change inducing he mig a ion o species looking o mo e sui able habi a s.
2.4. Clima e Changes
E ec s o clima e change a e nume ous; o ins ance, an inc ease in empe a u e may
accele a e he wa e e apo a ion a es, acili a ing he o es i e o mel ing o ice, modi ying
s eam low and inunda ion pa e ns [
59
]. S udies demons a e ha eshwa e ecosys ems
a e becoming wa me , mo e acidic and less oxygena ed [
60
]. I he wa e becomes oo
wa m o he i e ine species, hey may p obably dispe se o coole habi a s, impeded
by ac o s such as habi a a ailabili y and compe i ion [
5
]. Rega ding he s eams, he
clima e change c isis is pa icula ly mo e ala ming, as he olume o wa e is lowe han
in la ge i e s; he e o e, hea ing is much as e , comp omising se e al i al ecological
unc ions, such as g oundwa e echa ge, nu ien cycling and biodi e si y [
61
]. Fu he -
mo e, he measu es aken o o e come clima e change and wa e a ailabili y a e likely
o exace ba e biodi e si y loss because i ocuses mainly on ul illing human needs by
side-lining biodi e si y [
62
]. Conce ning aqua ic hyphomyce es, he empe a u e is e-
ga ded as a i al en i onmen al ac o a ec ing hei me abolic unc ions and ul ima ely,
g ow h and su i al [
63
]. Tempe a u e luc ua ions in luence he abundance o aqua ic
hyphomyce es species and ungal communi y composi ion [
63
–
65
], a ec ing o ganic ma e
decomposi ion [
66
]. An e icien and sus ainable wa e managemen amewo k should
conside ecosys em-based app oaches, ensu ing he esilience and long- e m s abili y o
eshwa e s [67].
2.5. O he Majo Pollu an s
F eshwa e s a e ulne able o a wide ange o pollu an s [
61
], such as ossil uels,
me als, xenobio ics and syn he ic ho mones, nega i ely impac ing he eshwa e bio a.
The a mosphe e is a sink o unwan ed gaseous by-p oduc s o igina ing mainly by he
combus ion o ossil uels, eleased in o he ai as ni ogen dioxide, sulphu dioxide, ca bon
monoxide o hyd oca bons [
68
]. These con aminan s a e gene ally washed away by ain,
making he eshwa e s mo e acidic. I is demons a ed ha co-exposu es o acid ain and
zinc oxide (ZnO) nanopa icles could accele a e s eam ungal communi y di e si y and
decomposi ion o o ganic ma e [69].
Mining ac i i ies mobilise sedimen s, inc ease me al concen a ions and modi y wa-
e pH [
2
]. Me als may esul in ungal biodi e si y loss in eshwa e s by educing he
occu ence o sensi i e species [
70
,
71
]. None heless, aqua ic hyphomyce es ha e been
epo ed om a ious me al-con amina ed s eams, p obably due o hei cellula ole -
ance and esis ance mechanisms o cope wi h me als [
72
–
76
]. Howe e , me al ole ance
mechanisms demand subs an ial ene gy, which may a ec hei e iciency in ep oduc ion,
g ow h [73,77–79] and hei unc ions (li e decomposi ion) [76].
Syn he ic ho mones ound in bi h con ol pills dis up he endoc ine sys ems o
eshwa e o ganisms such as in e eb a es and ish [
80
]. Xenobio ic compounds, such
as nonylphenols, which a e widely used as a su ac an [
81
], may also ac as endoc ine
dis up o s by imi a ing na u al ho mones, blocking o inhibi ing hei p oduc ion by he
o ganisms [
80
]. In aqua ic hyphomyce es, a low concen a ion o nonylphenols (50
µ
g L
−1
)
enhanced hei ep oduc i e capaci y [
82
]. In addi ion, an ibio ics in he was ewa e s may
inc ease he esis ance o he a ge ed o ganisms and may impac ecologically ele an
non a ge ed o ganisms [
83
]. Howe e , aqua ic hyphomyce es we e no e idenced o be
ole an o an ibio ics [84].
Fu he mo e, hea om indus ial and powe sec o e luen s [
12
] poses a signi i-
can h ea o eshwa e ecosys ems [
85
]. The wa e e ie ed om he wa e cou ses
o cool down a he mal plan is e e ed o he i e a much highe empe a u es [
86
].
Tempe a u e is one o he mos impo an ac o s modula ing he s uc u e o aqua ic

Wa e 2022,14, 605 6 o 16
hyphomyce e communi ies [
66
], which may lead o se e e consequences o eshwa e
ecological p ocesses.
Recen ly, nanoma e ials (nanopa icles and nanoplas ics), plas isphe e (mic obial com-
muni y es ablished on mic oplas ics) and mic oplas ics ha e been conside ed as a p edomi-
nan h ea o eshwa e s [
75
,
87
–
90
]. Inc eased elease o nanoma e ials in o he eshwa e s
may induce shi s in aqua ic hyphomyce e communi ies wi h impac s on biodi e si y and
ecological p ocesses [
87
]. In gene al, wi h an inc easing concen a ion o nanoma e ials in
he eshwa e s, he ep oduc i e a e o aqua ic hyphomyce es diminishes.
3. Biodi e si y Decline in F eshwa e s Is Ala ming bu Adequa e Knowledge on he
Biodi e si y o Aqua ic Hyphomyce es Is Missing
Besides c i ical bene i s p o ided by eshwa e s, such as he con ibu ion o he econ-
omy (e.g., elec ici y o ishe y) and p o isioning o ecosys ems se ices (e.g., d inkable
wa e ), eshwa e biodi e si y o e s an i eplaceable global biodi e si y da abank [
2
,
32
]. I
suppo s app oxima ely 9.5% o he o al species desc ibed [
2
,
12
,
62
]. In addi ion, 30% o he
o al eshwa e species is comp ised o e eb a es, including app oxima ely 17,800 ish,
700 bi ds [
85
] and 250 u le species [
91
]. I is well es ablished ha biologically di e se
eshwa e o ganisms con e adequa e ecological esilience in he ace o a changing en i-
onmen [
92
]. Howe e , we a e ye o ully app ecia e he biodi e si y o ungi, including
aqua ic hyphomyce es in he eshwa e s. The F eshwa e Animal Biodi e si y Assessmen
(FADA) [
91
] p o ides a la ge da abase on ish, ep iles, amphibians and some in e e-
b a es [
93
]. I is e iden ha biodi e si y assessmen and conse a ion s a egies ocus
on mac o-o ganisms [
94
]. The s udies on mic obes ela e mos ly o hei h ea s o la ge
o ganisms, a he han hei biodi e si y and conse a ion.
The IUCN Red Lis o Th ea ened Species p o ides only a pa ial co e o a ound 20%
o he known eshwa e species [
4
]. E en so, his limi ed biodi e si y co e age e eals ha
app oxima ely 30% o he species assessed a e ca ego ised as h ea ened [
4
,
85
]. Amongs
he h ea ened species, u les (62%), gas opods (47%), mammals (42%), amphibians (33%),
decapods (30%), ish (28%) and bi ds (20%) a e a isk o ex inc ion [
85
]. The mos ecen
Li ing Plane Repo 2020, de i ed om 3741 moni o ed popula ions o eshwa e species
(944 e eb a es), indica ed a decline in hei abundance by 84% in he las 50 yea s [
8
].
I sugges s ha he biodi e si y loss in eshwa e migh be a mo e c i ical han wha
is documen ed.
In he 2000s, knowledge o eshwa e biodi e si y has inc eased [
95
]. I is es ima ed
ha a ound 2000 species o aqua ic ungi a e es ic ed o eshwa e s [
21
,
91
]. To he bes o
ou knowledge, he i s and only ini ia i e o biodi e si y conse a ion o mic o ungi was
unde aken ia a p ojec (2007–2010) unded by he UK Da win Ini ia i e a emp ing o
conse e hese ulne able ungi in he e es ial, eshwa e and ma ine ecosys ems. This
p ojec p io i ised h ee specialis g oups, namely: (1) non-lichen- o ming Ascomyce es
and conidial ungi, (2) us s and smu s and (3) ch omis ans, chy ids, Myxomyce es and
Zygomyce es. I is su p ising ha almos a e 80 yea s o he disco e y o aqua ic hy-
phomyce es, he e a e no p ojec s dedica ed o assessing hei global biodi e si y. Howe e ,
he occu ence o aqua ic hyphomyce es, including he impac o en i onmen al s esso s,
a e well documen ed in some empe a e egions [
20
]. Sho age o well- ained axonomis s,
cons ain s in scien i ic capaci y, accessibili y o geog aphic egions and insu icien unds
ha e es ic ed in-dep h in es iga ions. The lack o adequa e knowledge ega ding hei
biodi e si y and dis ibu ion pa e ns [
20
] cu ails he de elopmen o an adequa e conse -
a ion plan. We a e ye o app ecia e he aqua ic hyphomyce es species ichness, pa e ns
o biodi e si y (alpha and be a), cosmopoli anism and endemism. The e is also a need
o dis inguish a e species om endange ed species; o he aspec s such as hei dis ibu-
ion pa e ns and adap a ions in he An h opocene emain unexplo ed. Mo eo e , he
biodi e si y o aqua ic hyphomyce es is g ea ly in luenced by seasons demanding ig-
o ous e o s h oughou he yea . The only s udy ega ding he popula ion gene ics o
aqua ic hyphomyce es, spanning wo yea s and wo seasonal cycles, demons a ed ha
Wa e 2022,14, 605 7 o 16
he gene ic di e si y o Te acladium ma chalianum a ied signi ican ly [
96
]. Addi ionally, a
unique s udy along b oad la i udinal g adien e eals ha he species ichness o aqua ic
hyphomyce es [
97
] and o he aqua ic ungi associa ed wi h lea li e [
65
] peaked a mid-
la i udes and diminished u he owa ds he ex emes o he la i udinal g adien [
97
].
A compelling solu ion o imp o e ou knowledge on a b oade scale may be o c ea e
awa eness among ecologis s o coope a e and conduc coo dina ed s udies ac oss he globe.
4. A Responsible App oach owa ds Unde s anding he Biodi e si y o All Fungi,
including Aqua ic Hyphomyce es, Is Needed
To da e, he conse a ion s a us o mos o he ungal species is unknown. Conse a-
ion agendas a ge ing ungi a e mainly ep esen ed by mac o ungi. They a e dis inguish-
able om o he ungi by hei isible spo e-bea ing leshy ui ing body. To da e, 425 mac o-
ungal species ha e been e alua ed by he IUCN Red Lis o Th ea ened Species [
98
].
Clea ly, he e is a endency o p o ec isually no iceable and amilia species, se e ely
educing ou ocus on he global ungal ex inc ion a e.
In isible o he naked eye, mic o ungi make up he g ea majo i y o undesc ibed
ungal axa [
15
]. They a e g ea ly p esen in ou li es and economy. Al hough some
mic o ungal species a e pa hogenic o plan s and animals, comp omising c ops, li es ock
p oduc ion and human beings, mos mic o ungi a e highly bene icial o ou socie y. Fo
example, he mic o ungi belonging o he genus Penicillium a e he sou ce o penicillin, a
g oup o an ibac e ial d ugs, which e olu ionised he heal h ca e indus y [
15
]. In addi ion,
he ood indus y elies g ea ly on yeas s o he p epa a ion o b ead and bee [
15
,
99
].
Mo eo e , as euka yo ic o ganisms, yeas s a e excellen model esea ch o ganisms, ushe ing
conside able ad ancemen s in mode n gene ics [
15
,
99
]. Mos p edominan ly, mic o ungi
a e c ucial o sus aining a wide ange o ecosys em p ocesses, main aining li e on he
plane [
15
,
65
]. The mos acknowledged is he myco hizal ungi, accomplishing a symbio ic
pa ne ship wi h app oxima ely 90% o all plan oo s [
100
]; hese ungi acili a e he plan s’
g ow h by imp o ing he acquisi ion o nu ien s om he soil; simul aneously he plan
oo s p o ide a eliable subs a e o myco hizal ungal g ow h and ep oduc ion [
101
]. In
gene al, mic o ungi ha e impac ed ou en i onmen o billions o yea s in a mul i ude
o ways and a e con inuously ouching millions o human li es. Howe e , hey need
special a en ion because hey a e la gely dis ega ded in he en i onmen . Ou lapse in
es ima ing he biodi e si y o he mic o ungi, including aqua ic hyphomyce es, impedes
hei inclusion in he conse a ion goals. Taking s eps owa ds illing his knowledge gap is
pi o al o assis ing e icien conse a ion policies and obus en i onmen al managemen
s a egies o sus ain eshwa e ecosys ems.
5. Emb acing Aqua ic Fungi in he F eshwa e Biodi e si y Conse a ion S a egies
The con inuous deg ada ion o eshwa e ecosys ems and he se ices hey p o ide
ha e led o he implemen a ion o a ious in e na ional o ganisa ions and ag eemen s (see
Table 1), aiming o bend he cu e o eshwa e biodi e si y loss [
85
]. Se e al biodi e si y
conse a ion o ganisa ions (Table 1) a e in ol ed in he da a ga he ing and biodi e si y
analysis. The indica o s p oduced by hese p ojec s a e gene ally used o moni o biodi e -
si y ends [
102
], aise awa eness among he public and policymake s [
103
] and in luence
go e nmen s and o he s akeholde s by p o iding an un es ic ed low o in o ma ion
and ad ice. Howe e , in mos cases, due o ine icien managemen , he da a ga he ed
emain unde u ilised, con ounding he de elopmen o da a-d i en policy decisions o he
es ablishmen o biodi e si y conse a ion a ge s [
104
]. Despi e suppo ing an imp essi e
numbe o species and p o iding se e al i eplaceable ecosys em se ices, eshwa e
biodi e si y is disp opo iona ely unde p io i ised. Fu u e s a egies and ac ions should
di e a g ea e ocus on he dis inc i e ecology o eshwa e o ganisms and hei h ea s.
Mo e speci ically, i is high ime o acknowledge ha we a e ye o edi ec ou a en ion o
an aqua ic ungal inclusi e conse a ion s a egy.
Wa e 2022,14, 605 8 o 16
Table 1. In e na ional miles ones in conse a ion s a egies.
Yea Miles one Conse a ion S a egies
1948 In e na ional Union o he
Conse a ion o Na u e (IUCN)
•Union composed by app oxima ely 1400 membe s (coun ies,
go e nmen s and ci il o ganisa ions).
•I is mainly in ol ed in da a ga he ing, analysis and educa ion.
•To in luence go e nmen , and s akeholde s by p o iding in o ma ion,
ad ice and pa ne ships.
1961 Wo ld Wildli e Fund o
Na u e (WWF)
•O ganisa ion wo king in wilde ness p ese a ion and educ ion o
human impac on he en i onmen .
•Responsible o publishing ‘The Li ing Plane Repo ’ e e y wo yea s
since 1998.
1964 Fi s edi ion o IUCN Red Lis
•The wo ld’s mos comp ehensi e ca alogue o he global conse a ion
s a us o se e al biological species was published.
1971 G een Peace
•Independen global ne wo k aiming o sa egua d en i onmen
and biodi e si y.
•Focus on issues such as: clima e change, de o es a ion, o e ishing,
comme cial whaling, gene ic enginee ing and an i-nuclea ma e ials.
1971 * The Ramsa Con en ion on we lands
•Fi s in e na ional ag eemen o conse a ion and sus ainable use o
we lands; i came in o o ce in 1975.
•Rep esen a i es o he con ac ing pa ies mee e e y h ee yea s o
discuss achie emen s and u he s eps.
1972
Uni ed Na ions Con e ence on he
Human En i onmen (S ockholm
Decla a ion)
•Held in S ockholm, esul ing in he beginning o an in e na ional
en i onmen al law, alongside wi h he i s ag eemen (26 p inciples and
109 ecommenda ions) ega ding en i onmen , de elopmen , human
igh s and p o ec ion o na u al esou ces.
1972 The Uni ed Na ions En i onmen
P og amme (UNEP)
•
O ganisa ion aiming o de elop in e na ional en i onmen al ag eemen s
on clima e change, managemen o ma ine and e es ial ecosys ems
(including inland wa e s) and g een economic de elopmen .
1973
Con en ion on In e na ional T ade in
Endange ed Species o Wild Fauna
and Flo a (CITES)
•One o he oldes conse a ion ag eemen s s ill in ac ion; i came in o
o ce in 1975.
•
Mainly o p o ec plan s and animals a isk o ex inc ion and ensu e ha
in e na ional ade in wild specimens does no h ea en hei su i al in
he wild.
1982 The Wo ld Resou ces Ins i u e (WRI)
•Comp ised by local and na ional go e nmen s alongside wi h p i a e
and public co po a ions.
•O e in o ma ion on global clima e change issues, sus ainable ma ke s,
ecosys em p o ec ion and en i onmen al go e nance se ices.
1988 In e go e nmen al Panel on Clima e
Change (IPCC)
•One o he Uni ed Na ion’s in e go e nmen al bodies.
•
Responsible o compiling knowledge on human-induced clima e change,
p o iding scien i ic in o ma ion o he impac s on he na u al, poli ical
and economic sec o s.
1991 * Wo ld Wa e Week
•
Non-p o i annual e en on global wa e issues, o ganised by S ockholm
In e na ional Wa e Ins i u e.
•Responsible o ind solu ions o he wa e - ela ed challenges h ough
pa ne ships wi h o ganisa ions om a ious coun ies and sec o s.
1992 Ea h Summi -Con en ion on
Biological Di e si y (CBD)
•E en held in Rio de Janei o; i came in o o ce in 1993, es ablishing a
mul ila e al ea y (CBD).
•
Ta ge he conse a ion o biodi e si y in all i s aspec s, sus ainable use o
na u e componen s and ai sha ing o bene i s a ising om
gene ic esou ces.
Wa e 2022,14, 605 9 o 16
Table 1. Con .
Yea Miles one Conse a ion S a egies
2000 The Ca agena P o ocol
•A p o ocol ha a ises as a supplemen a y ag eemen o he CBD (1992).
•Aim o gua an ee biosa e y in he mo emen s o li ing modi ied
o ganisms (LMOs) be ween coun ies; i en e ed in o o ce in 2003.
2000 The Millennium De elopmen
Goals (MDGs)
•Comp ises eigh in e na ional de elopmen goals.
•
Focus mainly on human popula ion needs, only goal 7, a ge ed o ensu e
en i onmen al sus ainabili y by 2015.
2001–
2005
The Millennium Ecosys em
Assessmen (MEA)
•Comp ehensi e assessmen , a ge ing he consequences o ecosys ems
changes due o an h opogenic ac i i ies as well as es ablishing scien i ic
basis o he de elopmen o conse a ion and sus ainable de elopmen .
2002 The Wo ld Summi on Sus ainable
De elopmen
•Held in Johannesbu g (“Rio + 10”), i uni ed heads o s a e, delega es,
NGOs and businesses g oups.
•Add ess he imp o emen o people’s li es while conse ing na u e in a
wo ld wi h a g owing popula ion and e e -inc easing esou ce demands.
2002 S a egic Plan o he Con en ion on
Biological Di e si y
•
A new s a egic plan o e ec i ely hal he loss o biodi e si y and secu e
he con inui y o i s bene icial uses h ough he conse a ion and
sus ainable use o i s componen s.
•Raise he conce n o ai and equi able sha ing o bene i s a ising om
no el gene ic esou ces.
2010 The Uni ed Na ions Wo ld Wa e
De elopmen Repo (WWDR)
•The UN-Wa e ’s epo ackling wa e demand and sani a ion issues,
published by UNESCO.
•I p o ides insigh s and knowledge conce ning he s a e, use and
managemen o eshwa e s, as well as o mula ion and implemen a ion
o sus ainable wa e policies.
2010 S a egic Plan o Biodi e si y
Re ision 2011–2020
•Held in Nagoya, Japan, he mee ing upda ed he S a egic Plan o
Biodi e si y o he 2011–2020 pe iod, p o iding a amewo k on
biodi e si y o he UN and pa ne s engaged in
biodi e si y managemen .
•
Resul ed in he signa u e o he Nagoya P o ocol and he de elopmen o
he Aichi Biodi e si y Ta ge .
2010 The Nagoya P o ocol
•A supplemen a y ag eemen o he CBD (1992).
•
To a ge he implemen a ion o one om he h ee objec i es o he CBD:
he ai and equi able sha ing o bene i s a ising ou o he u ilisa ion o
gene ic esou ces, se ing ou obliga ions o i s con ac ing pa ies.
2010 The Aichi Biodi e si y Ta ge s
•A 10-yea plan, c ea ed by he CDB pa ies, sub-di ided in o 20 a ge s,
aiming o p o ec and conse e na u al sys ems.
2010
The In e go e nmen al Science-Policy
Pla o m on Biodi e si y and
Ecosys em Se ices (IPBES)
•In e go e nmen al o ganisa ion es ablished o imp o e he in e ace
be ween science and poli ics on issues o biodi e si y and
ecosys em se ices.
•I en e ed in o o ce in 2013.
2012 The wo ld’s 100 mos
h ea ened species
•IUCN epo wi h he 100 mos h ea ened species was published by he
Zoological Socie y o London as a book, named P iceless o Wo hless?
•
The lis con ain species h ea ened o ex inc ion, s essing ha ‘all species
ha e an inhe en igh o exis ’.
2015 Sus ainable De elopmen
Goals (SDGs)
•De eloped by he UN o eplace he MDGs.
•The SDGs un om 2015 o 2030, se ing a 15-yea plan o achie e 17
goals, aiming o end po e y, p o ec he plane and imp o e he quali y
o li e on ea h.
Wa e 2022,14, 605 16 o 16
106.
Gonçal es, S.C.; Haelewa e s, D.; Fu ci, G.; Muelle , G.M. Include All Fungi in Biodi e si y Goals. Science
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,373, 403.
[C ossRe ]
107.
Maye s, J. Wa e Ecosys em Se ices and Po e y Unde Clima e Change: Key Issues and Resea ch P io i ies: Repo o a Scoping Exe cise
o Help De elop a Resea ch P og amme o he UK Depa men o In e na ional De elopmen ; IIED: London, UK, 2009.