7/28/2019 Crypto My Cota

1/3

ARTICLE

v o l u m e 2 n o . 2 173

2011 International Mycological Association

You are free to share - to copy, distribute and transmit the work, under the following conditions:Aibin: Youmustattributetheworkinthemannerspeciedbytheauthororlicensor(butnotinanywaythatsuggeststhattheyendorseyouoryouruseofthework).

Nn-mmia: Youmaynotusethisworkforcommercialpurposes.

N iai wks: Youmaynotalter,transform,orbuilduponthiswork.

For any reuse or distribution, you must make clear to others the license terms of this work, which can be found at http://creativecommons.org/licenses/by-nc-nd/3.0/legalcode. Any of the above conditions can be waived if you get

permission from the copyright holder. Nothing in this license impairs or restricts the authors moral rights.

INtroductIoN

The designation cryptomycota was introduced by Jones

et al. (2011) toaccommodateawell-supportedclade(using

ribosomalDNA (rDNA)phylogenies)of organismsputatively

branchingdeepwithinthefungalradiation.Therankofphylum

is the most appropriate for this group as current results show

that it has fungal characteristics but is distinct from other fungi

innothavingachitin-richcellwallinthemajorstagesofitslife-

cyclesofaridentied,includingputativetrophicinteractions.However, Cryptomycota was not validly published as a

scienticnameinthatworkasnoLatindiagnosiswasprovided

(McNeillet al.2006:Art.36).ALatindiagnosisisprovidedhere

inordertoformallyestablishthename.Inaddition,comments

are made on our decision to introduce this name rather than

take up the earlier informal name Rozellida, and on the

distinctivefeaturesofthephylumanditsposition.

tAXoNoMY

cypmya M.D.M.Jones&T.A.Richards,phy.n.

MycoBankMB563383

Etymology: crypto- hidden; and -mycota,aphylumoffungi.

Fungiunicellulares,zoosporisunicellularis,uniagellatibus,agellis

microtubularis,cystessinetunicachitinosavelcellulosa.Consortia

epibionticaformata.

Fungi unicellular, zoospores single-celled with a single

microtubular agellum,and cystswithout a chitin/cellulose

cellwall.Formingepibionticassociations.

Representatives: GenBank accession nos AJ130857,

AJ130849.1,AJ130850,FJ687265,FJ687267andFJ687268,

and Rozella.

Illustrations: Jones et al.(2011:gs1d,2ae).

dIScuSSIoN

It has been demonstrated that Rozella occupies a deep

branching position in phylogenetic analyses of kingdom

Fungi(Jameset al.2006a,b),althoughbootstrapsupportfor

this relationship is inconsistent and often weak in the most

comprehensivelysampledphylogenies(Jameset al.2006a,

b, Jones et al.2011). Thename Rozellidawas coinedby

Laraet al.(2010)toaccommodateRozella and a number of

environmentalsequences that formadistinctclade,butwe

refer to this group henceforth as Cryptomycota for reasons

indicatedbelow.Joneset al.(2011)showedthatCryptomycota

are more diverse than previously recognised and that the

moleculardiversityofthisgroupmaybeasdiverseastherest

of the known FungiaccordingtorDNAgenemarkers.

Members ofCryptomycota are found in freshwater, soil,

sediment,andsomemarinehabitats.Joneset al.(2011)used

Validation and justication of the phylum name Cryptomycota phy. n.

MeredithD.M.Jones1,2,ThomasA.Richards 1,2,DavidL.Hawksworth3,andDavidBass2

1SchoolofBiosciences,UniversityofExeter,ExeterEX44QD,UK;correspondingauthore-mail:d.bass@nhm.ac.uk

2DepartmentofZoology,NaturalHistoryMuseum,CromwellRoad,LondonSW75BD,UK

3

DepartamentodeBiologaVegetalII,FacultaddeFarmacia,UniversidadComplutensedeMadrid,PlazaRamnyCajal,28040Madrid,Spain;andDepartmentofBotany,NaturalHistoryMuseum,CromwellRoad,LondonSW75BD,UK

Absa:The recently proposed new phylum name Cryptomycotaphyl.nov.isvalidlypublishedinordertofacilitateits

useinfuturediscussionsoftheecology,biology,andphylogeneticrelationshipsoftheconstituentorganisms.Thisname

ispreferredoverthepreviouslytentativelyproposedRozellidaasnewdatasuggestthatthelife-styleandmorphology

ofRozella isnotrepresentativeofthelargeradiationtowhichitandother Cryptomycotabelong.Furthermore,taxaat

higherrankssuchasphylumareconsideredbetternotbasedonindividualnamesofincludedgenera,butratheronsome

specialcharacteristicsinthiscasethecrypticnatureofthisgroupandthattheywereinitiallyrevealedbymolecular

methodsratherthanmorphologicaldiscovery.Ifthegroupwerelaterviewedasamemberofadifferentkingdom,the

nameshouldberetainedtoindicateitsfungalafnities,asisthepracticeforotherfungal-likeprotistgroups.

Article info:Submitted26September2011;Accepted2November2011;Published11November2011.

Ky ws:

chitin

chytrid

Fungi

phylogeny

Rozella

Rozellida

doi:10.5598/imafungus.2011.02.02.08 IMA FuNguS voluMe 2 No 2: 173175

7/28/2019 Crypto My Cota

2/3

Jns et al.

ARTICLE

4 i m a f u n G u S

lineage-specicuorescence in situ hybridization (FISH),cell

wall stains, and immuno-uorescence staining to show two

distinct lineages within Cryptomycota,whichcomprisedovoid

cells ofca.5mdiam,existinginatleastthreemorphologies

in freshwater environments: uniagellate zoospores, more

variably-shapedcellswithoutagellaattachedtoothereukaryotic

microscopicorganisms(e.g.diatomhosts),andnon-agellatecysts.Noneofthesestageswereshowntopossessachitinor

cellulosewall,althoughotherlife-cyclephaseswithachitinand/

orcellulosecellwallmayremainundetected.Achitincellwallis

sometimescitedasdeningfeatureofkingdomFungi, although

we note that this is not a reliable diagnostic feature as distantly

related protist groups also possess chitin on their cell surface

(e.g.Kneippet al.1998).

ThenameRozellidawasappliedtothisphylumbyLara

et al.(2010)butinaninformalwaybetweeninvertedcommas

andwithnoformaldiagnosis.TheICZN(InternationalCode

of Zoological Nomenclature; International Commission on

Zoological Nomenclature 1999) does not apply to namesabovetherankoffamily-group,butifitwereinthoseranks

it would be viewed asunavailable asa conditional name

(Art. 15.1). For names introduced under the ICZN which

later are found to belong to Fungi, the ICN (International

Code of Nomenclature for algae, fungi, and plants) now

acceptsthemasavailableunderArt.45.4(asrevisedatthe

MelbourneCongressinJuly2011;McNeillet al.2011).Thus,

noLatindiagnosiswasrequired,asitwasforfungalnames

introducedbetween1935and1January2012).However,we

are inclined not to accept Rozellida because of the use of

theinvertedcommassuggestingtheusagewasa tentative

suggestion and in any case note that it is not mandatory tofollowtheprincipleofpriorityofpublicationfornamesabove

therankoffamily(ICN)orfamilygroup(ICZN).Indeed,the

ICZNdoesnotcoverrankshigherthanfamilygroup.

We decided that it would be better not to denitely

establish a name based on Rozellaforseveralreasons:

(1) The fungal terminationtobeusedfornames inthe

rank of phylum is -mycotaundertheICN(McNeillet al.2006;

Art16.4),and thatterminationhasalsobeenusedforphyla

traditionally studied by mycologists but which are no longer

considered Fungi butplaced inother kingdoms.Examples

include Hyphochytriomycota R.H.Whittaker(Whittaker1969:

154)nowplacedinStraminipilaM.W.Dick2001,Myxomycota

Bold(Bold1957:152)forslimemouldsintheProtozoa, and

Oomycota Arx (Arx 1967: 16) for fungal analogues in the

Straminipila.Thispractice hasbeenemployedin standard

referenceworks (e.g. Kirket al. 2001) andalso themost

recenttextbooks(e.g.Mooreet al.2011).

(2)Cryptomycota represent a very diverse radiation,

potentiallyequivalenttoorlargerthantherestoftheknown

fungi. Of the three lineageswithin the radiation for which

morphologicaldataexist,Rozellaappearstobeexceptional

in that it is primarily an intracellular parasite; indeed the

possession of intracellular sporangia is included in the

generic description ofRozella species(Held1981).Toextend

the implication of this life-cycle characteristic across the rest

of the radiation where there is no evidence of this life-

cyclecharacteristicwouldbemisleading.Laraet al.(2010)

were also hesitant commending the use of the proposed

namebetweenquotationmarksuntilmorphologicaland/or

ultrastructuralsynapomorphiesaredenedtodiagnoseand

validatethisentiregroup.Joneset al.(2011)demonstrate

that this key characteristic ofRozelladoesnotseemtoextend

across the whole group and therefore the name Rozellida isnotrepresentativeofthegroupasawhole.

(3) Itisimportanttorecognizethatourcurrentknowledge

of the life stages of the newly discovered Cryptomycota

and of Rozella isvery incomplete.As Joneset al. (2011)

suggest, chitin may be present in the walls of some currently

unknown Cryptomycotalife-cyclestage(s)and/orpresentin

uncharacterized lineages within Cryptomycota,andevenin

currently unknown stages in Rozella.Itwouldbepremature,

therefore, to separate Cryptomycota from the kingdom Fungi

on the single character that they do not possess chitin walls

(which,asmentionedaboveisnotdiagnosticforFungi).

(4)Cryptomycota have some strong resemblances toChytridiomycota (chytrids) in both structure (e.g. agellar

apparatus)andecology,ifnotincellwallchemistry.Thereis

noagreeddeningnon-molecularcharacteristicforidentifying

the boundaries of kingdom Fungi.Therefore,asseveralother

key characteristics are shared by Cryptomycota and some

Fungi, the former are most sensibly and parsimoniously

considered as belonging to the latter as they form the closest

branches on phylogenetic trees (James et al. 2006a, b,

Laraet al. 2010,Jones et al.2011).Thisstanceisentirely

consistent with the historical position regarding Rozella: for

the last 40 years leading mycologists have classied this

genus within Fungi(e.g.Held,1981;Kirket al.2008).(5)Cryptomycota(includingRozella)consistentlybranch

with Fungiinallphylogeniessofarconstructed.However,their

position as the primary branch within fungi is much weaker

(e.g.Jameset al.2006;Joneset al.2011).Indeed,theycould

actually occupy a higher branching position within Fungi.If

this is the case, their lack of some traditionally diagnostic

fungal features such as a chitin cell wall may be the result of

secondary losses, which would not preclude them from being

considered Fungi.Inthiscase,excludingCryptomycota from

the Fungicould potentially make the rest of fungi paraphyletic

ahighlyundesirableandnotlogicallysustainablesituation.

Intheabsenceofastrongmorphologicalargumenttoexclude

this group from the fungal kingdom we must therefore look

totheonlyavailabledata,whichisphylogenetic,andargues

that Cryptomycota are most reasonably considered to be

withinFungi.

(6)Consequently,weagreewithLaraet al.(2010)that

there are sound reasons for considering Rozella(andnow

we suggest otherCryptomycota)asFungi.Whetherornot

Cryptomycota other than Rozella prove tobephagocytotic

(whichinitselfwouldnotbeasufcientlystronglydeterministic

traitfor inclusion in orexclusion from Fungi, as some

plant lineagesandoomyceteshavealsolostphagotrophy),

theirchytrid-likeuniagellatezoosporestageandparticularly

their phylogenetic position argue most parsimoniously for a

fungalafliation.

7/28/2019 Crypto My Cota

3/3

Validation of the phylum name Cryptomycota

ARTICLE

175v o l u m e 2 n o . 2

(7) Thenamesusedfortaxaatthehighestranks,suchas

phylum, are better not based on names of included genera,

but rather on some special characteristic, as is the case with,

forexample,the phylaAscomycota and Basidiomycota.In

this way the names immediately convey some feature of

the taxon. In this case,wehighlight the cryptic nature of

Cryptomycota in that they were hidden from science untilrevealed bymolecularmethods rather thanmorphological

discovery.

Inconclusion,weconsider the formal validation of the

name Cryptomycotatobejustied,andcommenditforuse

forthisgroupoforganismsasitemphasisesthefungalafnity

and attributes of the organisms so far known within this

group.Evenifinsomefutureclassicationtheseorganisms

were placed outside the Fungi, we consider the name should

beretainedtoreecttheirnatureasfungalanalogues.

AcKNoWledgeMeNtS

WethankRamonMassana,IreneForn,CaterinaGadelha,andMartin

Eganforusefuldiscussions,andJoostAStalpersforcheckingthe

Latindiagnosis.D.L.H.acknowledgessupportfromtheMinisterio

deCienciaeInnovacininSpain(projectCGL2008-01600).

reFereNceS

ArxJAvon(1967)Pilzkunde: Ein kurzer Abriss der Mykologie under

besonderer Bercksichtigung der Pilze in Reinkultu. Lehre: J

Cramer.

BoldHA(1957)Morphology of Plants. NewYork:HarperRow.

HeldAA(1981)Rozella and Rozellopsis: naked endoparasitic fungi

whichdressupastheirhosts.Botanical Review47:451515.

International Commission on Zoological Nomenclature (1999)

International Code of Zoological Nomenclature. 4thedn.London:

InternationalTrustforZoologicalNomenclature.

JamesTY,KauffF,SchochCL,MathenyPB,HofstetterV,CoxCJ

[and64others],(2006a)Reconstructingtheearlyevolutionof

Fungiusingasix-genephylogeny.Nature443:818822.

JamesTY,LetcherPM,LongcoreJE,Mozley-StandridgeSE,PorterD, Powell MJ, Grifth GW, Vilgalys R (2006b) A molecular

phylogeny of the agellated fungi (Chytridiomycota) and

description of a new phylum (Blastocladiomycota).Mycologia

98:860871.

JonesMDM, Forn I,GadelhaC,EganMJ,BassD,MassanaR,

Richards TA (2011) Discovery of novel intermediate forms

redenesthefungaltreeoflife.Nature474:200203.

KirkPM,CannonPF,DavidJC,StalpersJA(eds)(2001)Ainsworth

& Bisbys Dictionary of the Fungi. 9th edn.Wallingford: CABI

Publishing.

KirkPM,CannonPF,MinterDW,StalpersJA(eds)(2008)Ainsworth

& Bisbys Dictionary of the Fungi. 10th edn.Wallingford:CABIPublishing.

Kneipp LF, Andrade AF, de Souza W, Angluster J, Alviano CS,

TravassosLR (1998)Trichomonas vaginalis and Trichomonas

foetus: expression of chitin at the cell surface.Experimental

Parasitology89:195204.

LaraE,MoreiraD,Lpez-GarciaP(2010)Theenvironmentalclade

LKM11andRozella form the deepest branching clade ofFungi.

Protist161:116121.

McNeillJ,TurlandNJ,MonroA,LepschiB(2011)XVIIIInternational

BotanicalCongress:preliminarymailvoteandreportofcongress

actiononnomenclatureproposals.Taxon60:15071520.

MooreD,RobsonGD,TrinciAPJ(2011) 21st Century Guidebook to

Fungi. Cambridge:CambridgeUniversityPress.

Whittaker RH (1969) New concepts of kingdoms of organisms.

Science163:150160.