Notes and brief articlesThe perithecia are immersed within the sub-

stratum in small clusters of 2-5, vertically oriented,non-stromatic and partially erumpent. They arebrown, globose to flattened-globose, smooth, 500-545 x 500-545 jim. The perithecial wall is 10-15 jim thick and pseudoparenchymatous; it con-sists of distinct outer and inner layers. The outerlayer is 8-12 jim thick and composed of 2-3 tiersof tangentially elongated, compactly arranged, lightbrown cells. The inner layer is 2-4 jim thick andcomposed of loosely arranged, thin-walled, hyalinecells. The perithecial neck is nearly central, short,straight and tubular, thin-walled, 75-90 x 60-75 jim; its wall is 9-12 jim thic.k and is composedof 3-5 layers of compactly arranged, light-browncells. The ostiole is simple and lined with short,slender and upwardly projecting periphyses. Theasci are unitunicate, thin-walled (the wallevanescent at maturity), ellipsoid, non-stalked,non-amyloid, becoming free in the perithecialcavity, 8-spored, 40'2-48"4 x 12'8-21'5 jim. Theascospores are two-celled with a median septumand with an appendage at each end, thin-walled,hyaline, densely granular, fusiform, 15'0-22'5 x4'5-6-0 jim (excluding appendages); they are bi- ortri-seriate. The appendages are simple, persistent,narrow, short, straight to slightly bent, filiform,with pointed ends, 7'5-10'0 x 0'1-0'2 jim. Para-physes are absent.

The thin-walled ostiolate perithecia, the uni-tunicate asci which become free from the hymen-ium and come to occupy the cavity of theperithecium and the evanescent nature of the asci

which characterize this fungus are typical of theDiaporthales in which the fungus is thereforeplaced. The fusiform, two-celled and typicallypersistent bisetulate ascospores are unique and arenot found in any genus of the family so far known(Muller & von Arx, 1973; Barr, 1978; Hawksworthet al., 1983; Monod, 1983). The setulae areprotoplasmic extensions of the two cells, unlike inspecies of Gnomonia where gelatinous appendagesare not always visible. A new genus and a newspecies are proposed here to accommodate thefungus.

I am grateful to Reverend Fr V. Dierckx, S.J.,for kindly providing the Latin diagnoses of thenew taxa and to the University Grants Commissionfor the Award of a Junior Research Fellowship.

REFERENCES

BARR, M. E. (1978). The Diaporthales in North Americawith emphasis on Gnomonia and its segregates. Myco-logia Memoir 7, 1-232

HAWKSWORTH, D. L., SUTTON, B. C. & AINSWORTH,G. C. (1983). Dictionary of the Fungi, 7th edn.Commonwealth Mycological Institute, Kew.

MONOD, M. (1983). Monographie taxonomique desGnomoniaceae (Ascomycetes de l'ordre des Diapor-thales) I. Sydowia Beiheft 9, 1-315

MULLER, E. & VON ARX, J. A. (1973). Pyrenomycetes:Meliolales, Coronophorales, Sphaeriales. In The FungiIVA (ed. G. C. Ainsworth, F. K. Sparrow & A. S.Sussman), pp. 87-132. New York and London:Academic Press.

TRICLADIOSPORA, A NEW GENUS OF DEMATIACEOUS HYPHOMYCETESWITH STAUROSPOROUS CONIDIA FROM SUBMERGED DECAYING

LEAVES

BY A. NAWAWI AND A. J. KUTHUBUTHEEN

Department of Botany, University of Malaya, 59100 Kuala Lumpur, Malaysia

Illustrated accounts are given of two new dematiaceous hyphomycetes with staurosporousconidia occurring on submerged decaying leaves. They are Tricladiospora gen.nov., typespecies T. stricta sp.nov. and T. longissima sp.nov. Tricladium brunneum is transferred to thisgenus.

In our continuing studies on microfungi inhabit- conidia predominantly with one main axis bearinging submerged decaying leaves from freshwater two or rarely one or three laterals arising instreams in Malaysia, two new staurosporous dema- succession from different levels. The genus is intiaceous hyphomycetes were encountered. Except need of some revision for there is a great deal offor their dematiaceous nature they resemble very variation in conidiophore and conidium morph-closely members of Tricladium Ingold, a large ology. The configuration of Tricladium conidiagenus with an assemblage of mostly unrelated appears rather simple to evolve and there areanamorphs joined on the basis of having hyaline probably more fungi with ascomycetous and

Trans. Br. mycol. Soc. 90 (3), (1988) Printed in Great Britain

Notes and brief articles

Fig. 1. Tricladiospora strieta. (A-D) Conidiophores bearing conidia at various stages of development;(E) a conidium proliferating to produce another conidium; (F) four conidia from leaf.

Trans. Br. mycol. Soc. 90 (3), (1988) Printed in Great Britain

A

Notes and brief art icles

50 Jim

shaped conidia are also dark and thick-walled.Such a combination of cha racters is not found inan y other hyph om ycetes.

Fig. 2 . Tricladiospora longissima. (A- B) Two stages in conidial formation; (e ) three conidia from leaf.

basidiomycetous affinity with such conidial morph-ology. We arc reluctant to broaden even furtherthe genus by inclusion of dematiaceou s forms. Theerection of a new genus to accommodate th e twonew fungi below seems just ified. They are hypho- Tricladiospora gen .nov .mycetes with dark, thick-walled conidiophores Hyphomycetes dematiacei, Conidiophora macronema-that proliferate percurrently. Their Tricladium- tosa, mononematosa, singularia vel caespitosa, indeter-

Trans. Br . mycol. Soc. 90 (3), (1988) Primed ill Great Britain

Notes and brief articles

3

7

-

4 5 6 8

9

40/lm

10 IIFigs 3-11. For captions see page 494.

Trans. Br. mycol. Soc. 90 (3), (1988) Printed in Great Britain

Notes and brief articles

minata, simplicia, laevia, brunnea, erecta vel f1exuosa.Cellulae conidiogenae in conidiophoris incorporatae,terminales, monoblasticae, prolificantes percurrentes.Conidia holoblastica, solitaria, acrogena, coloria, multi-septata, staurospora; axis principalis elongatus ad basirntruncatus, apicem attenuatus, plerumque cum 1-3brachiis lateralibus, singularibus, seriatim crescentibus,cum isthmis basalibus, liberata dissolutione septi basali.

Species typica Tricladiospora stricta sp.nov.

Dematiaceous hyphomycetes . Conidiophoresmacronematous, mononematous, single to caes-pitous, indeterminate, simple, smooth, brown,erect to flexuous. Conidiogenous cells integrated,terminal, monoblastic, proliferations percurrent.Conidia holoblastic, solitary, aerogenous , coloured,multiseptate, staurosporous; main axis elongated,truncate at the base, tapered towards the apex,with 1-3 lateral branches, single, in succession,with basal constrictions, liberated by dissolution ofbasal septum.

Tricladiospora stricta sp .nov. (F igs 1, 3-6)

Coloniae effusae, plerumque inconspicuae. Myceliumimmersum vel superficiale, ex hyphis ramosis, septatis,brunneis, 2-3/lm crassis compositum. Conidiophoramacronematosa, mononematosa,singulariavelcaespitosa,erecta, indeterminata, simplicia, laevia, brunnea, rectavel f1cxuosa, 2-t2 septata, 20--64 x 3-4 pm. Cellulaeconidiogenae in conidiophoris incorporatae, terminales,monoblasticae, prolificantes percurrentes. Conidia holo-blastica, solitaria, acrogena, brunnea, staurospora; axisprincipalis rectus, 54-89 I' m longus x 3"5-4 /lm crassusad basim, 11-16 septatus et truncatus, apicem atten-uatum ; rami laterales 1-2, ad basim constricti, recti,cylindrici, acuti, 4-5 septati, 33-61 pm longi, 2-2'5 I'mcrassi, seriatim crescentibus, liberata dissolutione septibasali.

Ex foliis angiospermis purrescentibus in f1umineimmersi, Pasuh Forest Reserve, Negri Scmbilan, 3 Feb.,1987, A. J. Kuthubutheen , 1M1 315800, holotypus.

Colonies effuse, mostly inconspicuou s. Myceliumimmersed or superficial, composed of branched,septate, brown hyphae, 2-3 I'm diam. Conidia-phares macronematous, mononematous, single tocaespitose, indeterminate, simple, smooth, brown,erect to flexuous, 2-12 septate, 20-64 x 3-4/lm.Conidiogenous cells integrated, terminal, mono-blastic, percurrent, cylindrical, with clear annel-

lations . Conidia holoblastic, solitary, aerogenous ,brown, smooth, con sisting of a straight main axis,54-89 I'm long , 3'5-4/lm wide at the base, 11-16septate, truncate at the base, sligh tly taperedtowards the apex; lateral branches 2, rarely 1, con-stricted at the base, straight, cylindrical, acute atthe apices , 4-5 septate, 33-61 pm long x 2-2'5 pmwide arising in order ; 1st branch usually ari sesfrom the 3rd cell from the base whil e the zndbranch usually ari ses from the 7th cell ; branches indifferent planes diverging at broad angles. Conidialiberated by dissolution of basal septa.

The conidia germinate readily on agar media byproducing germ-tubes from [he tips of the mainaxis and the lateral branches. On CMA the coloniesare dark brown with compact, greyish aerialmycelium, growth 35 mm in 30 d at 25-28 "C,sporulation sparse on dry agar but abundant onpartly submerged colony slivers. Conidia areproduced above the water level. Conidia formed onagar are similar in shape and size to those formedon the leaf piece s.

In terms of conidial morphology T. stricta iscomparable to Tricladium castaneicola Sutton(1975). However, conidia of T . castaneicola arehyaline with a longer main axis with up to 24 septa.Further, conidia of T . castaneicola are formedon branched, hyaline, sympodially proliferatingconidiogenous cells.

Tricladiospora stricta is also similar to Tricladiumbrunneum Nawawi (1974) in many respects. Conidiaof the latter are common in foam samples fromMalaysian rivers. They are readily recognized bythe brown colour of the main axis which is curvedto sigmoid and with thick, distinct septa. The twostraight, attenuated arms are thinner and lighter incolour. The fungus has recently been detected onsubmerged leaves incubated in moist chambers.The inclusion of this fungus in Tricladium is nowfelt to be inappropriate. Tricladium brunneum hasbeen re-examined. Similarities with Tricladiosporastrieta occur as follows. Both produce dark browncolonies of moderate growth rate with compactaerial mycelium. The methods of conidial develop-ment proceed along similar patterns, and th eirconidia are staurosporous with similar configura-tion and disposition. It is proposed herewith toredispose Tr icladium brunneum in Tricladiospora.

Figs 3--6. Tri cladiospora stricta .

Figs 3-5. Stages in conidial development.

Fig 6. T wo typical conidia.

Figs 7- 8. Tricladiospora bru/mea. Two conidia.

Figs 9-11. Tricladiospora longissima. Three conidia, one with two arms.

Trans . Br . my col. Soc. 90 (3), (1988) Primed in Great Britain

Notes and brief articles

Tricladiospora brunnea (Nawawi) comb .nov .(Figs 7-8 )

Tr icladium brunneum Nawawi , T rans. Br. mycol.S oc. 63: 267 (1974).

Tricladiospora longissima sp.nov.(Figs 2, 9-11 )

Coloniae effusae, plerumque inconspicuae. Myceliumpartim superficiale, partirn in subs trato immersum , exhyphi s laevibu s, pall ide brunneis, ramosis, septatis,2-3 pm latis cornp ositurn. Conidiophora macronematosa,mononcmatosa, solitaria, erecta, simplicia, recta velflexuosa , brunnea, laevia, t-10 septata, 16-63 pm alta,4-5 pm lata . Cellulae conidiogenae in conidiophorisincorporatae , terminales, monoblast icae, prolificantespercurrentes. Conidia holoblastica, solitaria, acrogena,pall ide brunnea, sicca, staurospora ; axis principaliscylindricus, parum curvatus, 117-153 x 4-5 pm, cum13-17 septatis, ad basim truncatus, apicem subobtusum;rami laterales 3, raro 2, ad basim constricti, recti,cylindrici, 1-6 septati, 20-101 pm longi , 3-3'5 Itm crassi,seriatum crescentibus, liberata dissolutione septi basali.

Ex foliis angiospcrmis putrescentibu s in fiumineimmersi , Pasuh Forest Reserve, Negri Sembilan, 3 Feb.,1987, A. Nawawi, IMI 315801, holot ypu s.

Colonies effuse, mostly inconspicuous. My celiumpartly superficial, partly immersed in the sub-stratum, composed of smooth, pale brown,branched, septate 2-3 /lm wide hyphae. Conidio-phores macronematous, mononematous, solitary,erect, simple, straight to flexuou s, dark brownbelow, slightly paler and narrower above, 1-10septate, 16-63 /lrn high and 4-5 .um wide. Conidio-genous cells integrated, terminal, mono blastic proli-ferating percurrently, annellations several andconspicuous. Conidia holoblastic, solitary, aero-genous, pale brown, smooth, dry, staurosporous;main axis cylindrical, slightly bent (or ascending)

117-153 Itm long , 4-5 /lm wide with a truncatebase, 13-17 septate, narrowing slightly to thesubobtuse apex ; lateral branches 3, rarely 2,cylindrical with subobtuse apices, mostly 3-3'5 /l mwide growing out in order in different planes ,diverging at broad angles , straight, base smoothlyconstricted at point of origin, released at a basalseptum; 1st arm short, 1-3 septate, 20-42 lim long,usually arising from the 3rd cell from the base, zndarm 3-6 septate, 52-79/lm long, usually arisingfrom the 7th cell and the 3rd arm, 4-6 septate,70-101 /lm long arising from the 11th cell.

One characteristic feature of the conidia of T.longissima is that the rst-formed lateral branchremains short while the last formed usually exceedsthe znd branch in length. Conidia germinate veryslowly on CMA or MA by producing germ-tubesfrom the apices of the main axis and the lateralbranches. However, further growth did notoccur.

It is interesting to note that in the three speciesdescribed above the lateral branches of theirconidia, which arise in succession and lying indifferent plane s invariably arise from the 3rd andthe 7th cells of the main axis. The additionalbranch in T . longissima arises from the 11th cell.Conidia bearing one and two lateral branchesare also pre sent in T . strieta and T. longissima re-spectively, but they are comparatively few innumber.

REFERENCES

NAWAWI, A. (1974). Two new Tricladium species.Transactions of the Bri tish My cological Society 63,267- 272.

SUTTON , B. C. (1975). H yph om ycete s on cupules ofCastanea sativa . Transactions of the Brit ish My cologicalS ociety 64, 405-426.

BEVERWYKELLA CEREBRIFORMIS SP.NOV ., AN AERO-AQUATICHYPHOMYCETE FROM MALAYSIA

BY A. NAWAWI AND A. J. KUTHUBUTHEEN

Department of Botany, University of Malaya , 59100 Kuala Lumpur, Malaysia

B everwykella cerebriformis sp.nov., an aero-aquatic hyphomycete with multicellular, hollow ,lenticular-shaped conidia is described and illustrated.

This paper reports another aero-aquatic hypho-mycete found growing and sporu lating on pieces ofsubmerged decaying leaves incubated in moistchambers. It produces dark conidia which arelenticular in shape, each supported by a shortunbranched conidiophore. The conidium is rather

interesting and unique in its morphology, con-sisting of a layer of compact cells enclosing acentrally placed, dichotomously branched axis.This dematiaceous fungus is described here as anew species of Beverwykella Tubaki.

Trans. Br . my col. Soc. 90 (3), (1988) Primed in Great Britain