Trans. Br. mycol, Soc. 73 (1) 75-79 (1979)

[ 75 ]

Printed in Great Britain

A NEW DEMATIACEOUS HYPHOMYCETE FROM LEAF LITTER

By P. M. KIRK

Commonwealth Mycological Institute, Ferry Lane, Kew, Richmond, Surrey, England, TW93AF

A singular fungus, Lobatopedis foliicola P. M. Kirk gen. et sp.nov., is described from thedecaying leaves of deciduous trees collected in England. Its relationship with other foli-icolous hyphomycetes is discussed.

In temperate regions, hyphomycetes occurring onthe rotting wood and cupules of a large number ofdeciduous trees are well-documented (Ellis, 1971,1974, 1976; Sutton, 1973, 1975), whilst thoseoccurring on decaying leaves are relativelyunknown. Several studies on the mycoflora oftropical and subtropical leaf litter indicate thatthis substrate provides a rich source of interestinghyphomycetes (Pirozynski & Patil, 1970; Sutton,1978; Sutton & Hodges, 1975a, b, 1976a, b). Inthis paper a very distinct fungus which has beenfound in England on the decaying leaves ofdeciduous trees is described and its relationship tosome other hyphomycetes occupying a similarecological niche is discussed.

TAXONOMY

Lobatopedis P. M. Kirk gen.nov.(etym. Latin, "lobatus ', lobed + 'pedis', foot)

Coloniae amphigenae, effusae, pilosae, atrobrunneaead atrae, Mycelium immersum, ex hyphis septatis,pallide ad medio brunneis compositum. Conidiophoramacronemata, mononemata, erecta vel recumbens,recta vel flexuosa, simplicia vel cum 1 ad plures,brevis vel longis ramosa, medio ad atrobrunnea cumseptatis prominens, ex cellis basilaribus radiatimlobatis, atrobrunneis, parietibus orienta. Cellulae coni-diogenae in conidiophora incorporatae, terminalis,monoblasticae, determinatae. Conidia holoblastica,acrogena, solitaria vel catenata, sicca, medio ad atro-brunnea cum septatis prominens.Sp. typo L. foliicola P. M. Kirk

Colonies amphigenous, effuse, hairy, dark brown toblack. Mycelium immersed, composed of pale tomid brown septate hyphae. Conidiophores macro-matous, mononematous, arising singly from darkbrown, radially-lobed basal cells, erect to recum-bent, straight or flexuous, simple or with one toseveral short or long acropleurogenous branches,mid to dark brown with prominent septa. Conidio-genous cells integrated, terminal, monoblastic,determinate. Conidia holoblastic, aerogenous,solitary or catenate, dry, mid to dark brown withprominent septa.

Lobatopedis foliicola P. M. Kirk sp.nov.(etym. Latin, 'folium+ -cola ', leaf dweller)

Coloniae amphigenae, effusae, pilosae, atrobrunneaead atrae, Mycelium immersum, ex hyphis laevibus,septatis, pallidead medio brunneis, ramosis,parietibustenuis, usque ad 5 I'm compositum. Conidiophoramacronemata, mononemata, simplicia vel cum 1 adplures, brevisvellongis ramosis,medioad atrobrunneacum septatis prominens, parietibus crassis, levibus,80-1000 I'm alta, 9-15 I'm lata, ad basim 5-8 I'm lata,ad apicem 4-6 I'm lata, ex cellis basilaribus radiatimlobatis, usque ad 25 I'm latis, atrobrunneis, parietibusorienta. Cellulae conidiogenae in conidiophora incor-poratae, terminales, monoblasticae, determinatae.Conidia holoblastica, acrogena, solitaria vel catenata,sicca, simplicia, ellipsoidea, medio ad atrobrunnea,cum 7-14 septatis prominens, laevia, 5C>-90 I'm longa,9-15 I'm lata, ad basim 4-6 I'm lata.

In foliis dejectis putridis Quercus borealis Michx.,Close Wood, Meriden, Warwickshire, 30 Oct. 1977,M. C. Clark (MC 2121), IMI 222919, holotypus.

Colonies amphigenous, effuse, hairy, dark brownto black. Mycelium immersed, composed of thin-walled, smooth, septate, pale to mid brown,branched hyphae up to 5 I'm wide, producingfine filaments which penetrate the outer wall of thesubstrate epidermis and cuticle to give rise to theconidiophores. Conidiophores macronematous,mononematous, arising singly from dark brown,radially-lobed basal cells up to 25 I'm wide, erectto recumbent, straight or flexuous; simple or withone to several short or long acropleurogenousbranches, mid to dark brown with prominentsepta, thick-walled, smooth, 80-100 I'm or more inlength, 9-15 I'm wide, 5-8 I'm wide at the base,tapering to 4-6 I'm wide at the point of conidiumsecession. Conidiogenous cells integrated, terminal,monoblastic, determinate. Conidia holoblastic,aerogenous, solitary or catenate, dry, simple,ellipsoidal, mid to dark brown, with 7-14 promi-nent septa, thick-walled, smooth, 50-90 I'm long,9-15 I'm wide in the broadest part, 4-6 I'm wideat the base.

Specimensexamined. On dead leafof Fagussyloatica L.,Richmond Park, Surrey, U.K., 11 Aug. 1974, J. P.

0007-1536/79/2828-5200 $01.00 © 1979 The British Mycological Society

Lobatopedis foliicola gen. et sp.noo.

Fig. 1. Lobatopedis foliicola. Relatively short conidiophores arising from radially lobed basal cells. Solitaryand catenate conidia (x 720).

P.M. Kirk

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I

I 1

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25 urn

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Fig. 2. Lobatopedis joliicola. Relatively long conidiophores with short and long lateral branches bearing solitaryand catenate conidia (x 720).

Lobatopedis foliicola gen. et. sp.nov.Ellis, IMI 187023; On dead leaf of Quercus sp.,Temple Balsall, Warwickshire, U.K., 16 Sept. 1977,M. C. Clark (MC 2063), IMI 216754; On dead leaf ofQuercus borealis Michx., Close Wood, Meriden,Warwickshire, U.K., 30 Oct. 1977, M. C. Clark(MC 2121), IMI 222919, holotype,

DISCUSSION

The radially-lobed basal cells from which theconidiophores of L. foliicola originate are identicalto those found in the genera belonging to theBeltraniaceae (Sacc.) Nannizzi (pirozynski, 1963).This family consists, at present, of five genera,Beltrania Penzig (1882), Beltraniella Subramanian(1952), Beltraniopsis Batista & Bezerra (1961),Hemibeltrania Pirozynski (1963), and Pseudo-beltrania P. Hennings (1902), the genus EllisiopsisBatista (1956) being considered a synonym ofBeltraniella (Pirozynski &Patil, 1970). In Beltrania,Beltraniella and Beltraniopsis, in addition to theconidiophores, sterile or fertile setae are producedwhich also arise from radially-lobed basal cells.The basal cells which bear the setae and conidia-phores are produced from the submerged myce-lium by fine filaments which penetrate theepidermis and cuticle of the substrate. Thisarrangement is identical to that found in L.foliicola and is presumably a result of theirsimilar habitats. The species belonging in theBeltraniaceae are mainly tropical to sub-tropicalin occurrence and are usually found on the fallenand decaying leaves of a number of host plants.Beltrania rhombica Penzig (1882), the type speciesof the genus, and Beltrania querna Harkness (1884)are, however, also known from British collections -(Sutton & Pirozynski, 1965; unpublished data fromherb. IMI). The similarity between L. foliicolaand members of the Beltraniaceae is restricted tothese basal cells since the typically biconic append-icu1ate conidia produced on denticulate conidio-genous cells which characterize the Beltraniaceaeare quite different from the analogous structures ofL. foliicola.

Several other genera are characterized byconidiophores with more or less distinctly lobedbasal cells, e.g, Chaetendophragmia Matsushima(1971), Kramasamuha Subramanian & Vittal(1973), and Subulispora Tubaki (Tubaki &Yokoyama, 1971). The species belonging in thesegenera also have a predominantly foliicolous habitbut they are all morphologically distinct fromL. foliicola.

The monoblastic, determinate, non-cicatrizedconidiogenous cells of L. foliicola are similar tothose of species referred to the genus Hetero-conium Petrak (1949). However, in H. citharexyliPetrak (1949), the type species of the genus, the

conidiophores are often percurrent and arisedirectly from the mostly superficial myceliumand are clearly unlike those of L. foliicola.

Distinct features shown by the conidiophoresand conidia of L. [oliicola are the thickened wallsand septa . The appearance of the conidia is similarto that in Anavirga laxa Sutton (1975). The genusAnavirga Sutton (1975) was erected to accom-modate a single species, A. laxa, with triradiate andY-shaped conidia where the point of secessionfrom the conidiogenous cell is at the base of thelower arm. The species is predominantly cupu-licolous in habit but is also known from decayingleaves. Although the conidia are superficiallysimilar in structure, albeit not in shape, they arequite distinct when their mode of liberation isconsidered.

The point of conidium secession in L. foliicola,which is usually located midway between theapical and basal septum of the conidiogenous celland is apparent from the earliest stages of coni-dium formation, is distinctly constricted, thewall is noticeably thinner and pigmentation is lessdense. At maturity a circumscissile fracture occursleaving the distal part of the conidiogenous cellattached to the liberated conidium whilst theproximal part remains attached to the conidio-phore. The role of the conidiogenous cell istherefore twofold since in addition to producingthe conidium it also functions as a separating cell.This situation is unlike that which is found inA. laxa where the conidia secede from theconidiophore by an internal splitting of either theapical septum of the conidiogenous cell whichresults in part of the septum remaining attachedto the conidiogenous cell and part being liberatedwith the conidium or one of the septa at the baseof the lower arm of the conidium which leads topart of the conidium remaining attached to theconidiogenous cell. The conidia also have beenobserved to fragment into smaller segments by asimilar procedure. The point of secession doesnot, therefore, appear to be predetermined as inL. foliicola but is somewhat arbitrary. These twoquite different modes of spore liberation furthersuggest that L. foliicola and A . laxa are relatedonly through their similar habitats.

An unusual feature of the conidiophore of L.foliicola is the extreme variability in lengthexhibited. At one extreme there are relativelyshort (up to 150 pm in length), apically branchedor unbranched conidiophores and at the otherextreme a conidiophore which has short lateralbranches and, although arising from a character-istic lobed basal cell, resemble the lax aerialmycelium typical of A. laxa and is up to 1000 pmor more in length.

P. M. Kirk 79The author is indebted to Malcolm C. Clark

for making his collections available for study andto Brian C. Sutton for critically reading themanuscript.

REFERENCES

BATISTA, A. C. (1956). Systematic revision of thegenera Ellisiella Sacco and Ellisiellina Camera, andthe new genus Ellisiopsis. Anais da Sociedade deB iologia de Pernambuco 14> 16-25.

BATISTA, A. C. & BEZERRA, ]. L. (1961). Beltraniopsis-novo genero de fungos Dematiaceae. Publicacao,Institute de Micologia, Unioersidade do Recife,No. 296, pp, 2-10.

ELLIS, M . B. (1971). Dematiaceous Hyphomycetes.Kew : Commonwealth Mycological Institute.

ELLIS, M. B. (1974). Presidential Address. Demati-aceous Hyphomycetes in Britain. Transactions of theBritish Mycological Society 62, 225-23°.

ELLIS, M. B. (1976). More Dematiaceous Hyphomycetes.Kew : Commonwealth Mycological Institute.

HARKNESS, H. W. (1884). New species of Californianfungi. Bulletin of the Californian Academy of(Natural) Sciences 1, 39.

HENNINGS, P. (1902). Fungi S. Paulensis. II. a d.Puttemans collecti. Hedwigia 41, 295-311-

MATSUSHIMA, T . (1971). Microfungi of the SolomonIslands and Papua-New Guinea (Osaka) . Kobe:Matsushima.

PENZIG, O. (1882). Beltrania, un nuovo genere diiforniceti. Nota del dott. Nuooo giornale botanicoitaliano e Bolletino della Societa botanica italiana 14,72-75·

PETRAK, F. (1949). Neue Hyphomyzeten-Gattungenaus Ekuador. Sydowia 3, 259-266.

PIROlYNSKI, K. A. (1963). Beltrania and related genera.Mycologt'cal Papers 90, 1-37.

PIROlYNSKI, K . A. & PATIL, S. D. (1970). Some setoseHyphomycetes ofleaf litter in south India. CanadianJournal of Botany 48, 567-581.

SUBRAMANIAN, C. V. (1952). Fungi Imperfecti fromMadras. III. Beltraniella gen.nov. Proceedings of theIndian Academy of Sciences, Section B 36, 223-228.

SUBRAMANIAN, C. V. & VITTAL, B. P. P. (1973). Threenew Hyphomycetes from litter. Canadian Journalof Botany 51, 1127-1132.

SUTTON, B. C. (1973). Hyphomycetes from Manitobaand Saskatchewan, Canada. Mycological Papers 132,1-143·

SUTTON, B. C. (1975). Hyphomycetes on cupules ofCastanea sativa . Transactions of the British Mycol-ogical Society 64, 405-426.

SUTTON, B. C. (1978). Some dematiaceous hypha-mycetes from Eucalyptus leaf litter. Boletin de laSociedad Argentina de Botanica (1977) 18, 154-161.

SUTTON, B. C. & HODGES, C. S. (1975a). Eucalyptusmicrofungi : Codinaea and Zanclospora species fromBrazil. Nova Hedwigia 26, 517-526.

SUTTON, B. C. & HODGES, C. S. (1975 b). Eucalyptusmicrofungi : Two new hyphomycete genera fromBrazil. Nova Hedwigia 26, 527-533.

SUTTON, B. C. & HODGES, C. S. (1976a). Eucalyptusmicrofungi : Microdochium and Phaeoisaria speciesfrom Brazil. Nova Hedwigia 27,215-222.

SUTTON, B. C. & HODGES, C. S. (1976b). Eucalyp~us

rnicrofungi : Some setose hyphomycetes Withphialides. Nova Hedwigia 27, 343-352.

SUTTON, B. C. & PIROlYNSKI, K. A. (1965). Notes onMicrofungi. II. Transact ions of the British Mycol-ogical Society 48, 349-366.

TUBAKI, K. & YOKOYAMA, T. (1971). Notes on theJapanese Hyphomycetes, Transactions of the Mycol-ogical Society of Japan. 12, 18-28.

(Accepted for publication 18 October 1978)