Taxonomic studies on aquatic hyphomycetes

[ 4°5 ] Trans. Br. mycol. Soc. 78 (3) 405-437 (1982)

Printed in Great Britain

TAXONOMIC STUDIES ON AQUATIC HYPHOMYCETES III. SOME NEW SPECIES AND A NEW COMBINATION By E. DESCALS

AND

J. WEBSTER

Department of Biological Sciences, University of Exeter

Two new anamorph-genera of 'aquatic hyphomycetes' are erected: Tricladiopsis, to accommodate T. foliosa sp.nov. (type species) and T. flagelliformis sp.nov., and Sympodiocladium, with S.frondosum sp.nov. as sole representative. Other new anamorph species are: Articulospora atra, Flabellospora acuminata, Isthmotricladia britannica, Scorpiosporium rangiferinum, Sigmoidea aurantiaca, Sporidesmium ensiforme, Tricellula botryosa and Dwayaangam cornuta. Tetracrium amphibium is transferred to Flabellospora.

During the course of taxonomic studies in pure culture of the 'aquatic hyphomycetes', various species new to science were isolated from freshwater habitats, either from foam accumulated mainly during the cooler part of the year, or from decaying leavesand twigs. Their description and classification is the objective of this paper. The techniques used and sporulating conditions referred to below as 'standard' are those detailed in Descals, Webster & Dyko (1977). Articulospora atra Descals sp.nov. (Figs 1, 2, 19,20). (Etym.: refers to black colony pigmentation on MA 2 %) Cultura pura ex uno conidio seiuncta, in conditionibus supradictis. Colonia nigra, cum margine alba, tarde crescit, mycelium aerium abundans, fuscum et gossypinum. Status conidialis aquaticus, incolor, cellulae moniliformes. Sporulatio abundans in aqua distillata sterili ad 15-18°C post 3 dies. Conidiophora e hyphis repentibus, metasclerotiis vel filis hyphalibus, repentia, mononemata, usque ad 75 x 3-4 flm, simplicia vel sparsim ramosa. Cellulae conidiogenae discretae, mono-polyblasticae, cicatrices mucronatae, proliferatio sympodialis, 10-15 x 2-3 flm. Conidia holoblastica, vel singularia vel in fasciculis, vel apicalia vel subapicalia, staurospora, axis principalis clavatus, cum 1 (-2) cellulis, hilum mucronatum, 10-13 x 3-4 flm, 3-4 brachia seriatim gemmantia, coronata, parum pendula, unicellularia, 8-17 x 2-3 flm, liberata e dissolutione septi basalis. Status phialidicus aquaticus, formatus eodem tempore, incolor, parietibus cellularum levibus et tenuibus. Sporophora e hyphis repentibus, brevia, repentia, mononemata, simplicia vel sparsim ramosa, stipes multicellularis, metulae apicales vel laterales, breves, perpendiculares, inflatae. Cellulae sporogenae phialidicae, 3-8, acropleurogenae, singulares vel penicillatae vel verticillatae, saepe parum curvatae, inflatae, collum, si adest, rectum, 13-15 x 3-5 flm. Phialosporae bacilliformes, 0-1 septa, 3-7 x 0'5--0'7 flm, in fasciculis, germinatio non visa.

Holotypus e spuma in rivulo in Wester Ross, Hybernia, Sept. 1973, Webster et Descals (IMI 216359 et Herb. Exeter 3277).

Pure culture from single conidium on MA 2 % at standard conditions. Colony black, margin welldefined, narrow, white, growth slow and restricted, aerial mycelium abundant, dark and cottony. Conidial state aquatic, colourless, cells moniliform. Sporulation abundant on colony slivers in aerated or standing sterile distilled water at 15-18° for 3 days. Conidiophores arising from mycelial hyphae, torulose cells or mycelial strands, mononematous, up to 75 x 4 pm, main body growing into the water, delicate, base broad, cells few, branches 0 to few, lateral, distributed singly, antrorse at an acute angle, cells 1 to few. Conidiogenous cells mono- or polyblastic, apical or lateral, discrete, apex later broadened and flattened, detachment scar slightly mucronate to raised, broad, proliferation sympodial, 10-15 x 2-3 pm. Conidia single or in fascicles of up to three, apical or subapical, in close succession, branched, main body clavate, cells 1 (-2), detachment scar distinct, 10-13 x 3-4 um, branches 3-4, budding out in succession, coronate, antrorse at a broad angle, slightly pendulous, unevenly swollen, apex rounded, base constricted, unicellular, 8-17 x 2-3 pm, released readily at the basal constriction, dispersed singly in water. Phialidic state aquatic, colourless, appearing under the same conditions, especially on old colonies. Sporophores lateral, macronematous, mononematous, simple or branched singly, delicate, cylindrical, main axis multicellular, lateral branch perpendicular, swollen, apex broad, base slightly constricted, unicellular. Sporogenous cells phialidic, 3-8, aeropleurogenous, single, in penicils or verticils of up to 4, straight or slightly curved inwards, broadly ovate to ampulliform and inequilateral, apex

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Fig.

1.

Articulospora arra (pure culture, IMI 216359, water mount). Ontogeny, proliferation and supporting structures.

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Fig. 2. Articulospora atra (same material). A, detached conidia, some showing incipient polar germination (water mount, at scale A); B, phialidic state (from old culture) (in lactophenol cottonblue, drawn to scale B).

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narrowly extended, base slightly constricted, col- least one, often two, clearly lateral conidial larette (when present) cylindrical, 13-15 x 3-5 {lm. branches, which are not present in the other species, Phialospores bacilliform, unicellular (or with and its transfer to a new genus (Webster, 1954) may median septum), detachment scar indistinct, be justified. Titaea Sacc., a genus with mostly 3-7 x o· 5-0" 8 /lm, aggregating atthe apex in gloeoid tropical hyperparasitic terrestrial species, was last studied by Hansford (1946) and needs revision. Its fascicles. This fungus was isolated from a moorland stream type species is T. callispora Saccardo (1876), with on one occasion, although conidia have been seen in solitary conidia on short, erect conidiophores. other foam samples. There are apparently no other Conidial branching is also apical, but asymmetrical, records of its occurrence. and with acicular apices. The branched conidiophore heads, moniliform Articulospora is preferred to the above genera on cells, apical fasciculate arrangement of holoblastic the basis of closer resemblance in both morphology conidia and successive development of typically and ontogeny. three apical conidial branches relate this organism to Articulospora tetracladia Ingold. The black Dwayaangam cornuta Descals sp.nov. (Figs 3, pigmentation on MA 2 %, though, is not typical of 4, 22). (Etym.: cornutus: horn-shaped, referArticulospora. It is easily distinguished from A. ring to pairs of terminal conidial branches) tetracladia, A. grandis Greathead and A. infiata Cultura pura ex uno conidio sejuncta, super MA 2 % Ingold on conidial morphology and size. Articulos- in conditionibus supradictis. Colonia pall ide cremosa. para foliicola Matsushima (1975) and A. ozeensis Status conidialis incolor, cum parietibus cellularum Matsushima (1975), two tropical species from levibus et tenuibus. Sporulatio erratica et sparsa in aqua apparently terrestrial habitats, appear to be unre- distillata sterili ad 15-18° post 2 hebdomades. Conidiolated to Articulospora. Articulospora atra resembles phora micronemata, mononemata, gregaria. Cellulae A. monilijormis Ranzoni (1953) most closely. There conidiogenae laterales, singulares, perpendiculares, is no type for this species, but it forms a dull orange rectae, 7-12 x 3-4 usn, septum indistinctum, cicatrix lata, pigment. The conidia are of similar size, but the determinatae. Conidia solitaria, acrogena, multicellularia ,sed cum septis indistinctis, axis principalis rectus, branch apices are acute. A species with very similar obconicus, 17-30 x 6-7 11m, cum 1-5 cellulis, cicatrix conidia, Alatospora pulchella, has recently been truncata, 4 (-6-8) brachia, apicalia, bina, similia cornidescribed by Marvanova (1977) but is claimed to be bus bovinis, in duabus (-tribus) dimensionibus, phialidic. Three other holoblastic anamorph genera 30-52 x 5-7 /lm, e bifurcationibus brevibus, liberatio e are somewhat similar to A. atra: Tricellula, dissolutione septi basalis, natantia, erratice germinantia. Holotypus e ramunculo decorticato in flumine Culm Volucrispora and Titaea. Tricellula inaequalis van Beverwijk, the type species, was described from (SX 055955), Devon, Anglia, 14 January 1974, Descals airborne conidia with two branches appearing in (lMI 216351 et Herb. Exeter 3266). succession, the first apically and the second 'laterally' (from the sparse illustrations it appears Pure culture from single conidium on CMA at to be formed near the apex, but then swells standard conditions. Colony white to pale creamy, dichotomously). There is no black mycelial pig- margin diffuse, growth slow, aerial mycelium mentation. In van Beverwijk's description (1954) it absent. On MA 2 % colony creamy brown, margin is not clear whether conidia can appear grouped at diffuse, growth 6'5 em diam/z months, aerial the apex, but the genus diagnosis indicates phialidic mycelium white, sparse, near the centre. Sporuontogeny. On the other hand, Petersen's (1962) lation erratic and very sparse on 9-month-old isolate, based on material from unspecified sources colony slivers (CMA) partly submerged in sterile but apparently not the type, produced one to distilled water in a Petri dish at 15-18° for 2 weeks. several conidia budding out apically on the' con- Conidiophores micronematous, in scattered patches. idiophore branch' (conidiogenous cell); hence its Conidiogenous cells lateral, single, perpendicular, emendation to holoblastic ontogeny. The other two straight, obconical, monoblastic, determinate, species in Tricellula, T. aquatica Webster and T. 7-12 x 3-4 /lm, septa indistinct. Conidia solitary, curvata Haskins, are now also interpreted as aerogenous, staurosporous, multicellular, spanning out 50-80 x 40-70 /lm, septa indistinct in water, holoblastic. Volucrispora aurantiaca Haskins (1958), the primary body mostly straight, clavate, 17-30 x 6-7 type species, was isolated from soil. Its holoblastic /lm, cells 1-5, detachment scar truncate, branches conidia are sessile or on branched conidiophores, 4 (-6-8), in pairs, curved and pointed, resembling and bear apical and subapical branches which are bovine horns, mostly in one plane, 30-52 x 5-7/lm, on short dichotomies on the main body, attached by a very narrow isthn1us. Volucrispora released at a basal septum, dispersed on water, graminea Ingold, McDougall & Dann (1968), has at

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Fig. 3. Dw ayaangam cornUla (pure culture , IMI Z16351, water mount, except L : drawn from lactophenol cotton-blue for septation) . A, B, C, D, H, J, M, ontogen y. E, F, G, I, K, L, detach ed conidia. E, F, K, typical morpholog y. F, anastomosing apex. K, lateral germination.

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Fig . 4. Dwayaangam comura (same material ). A-D, F, hyphal morphology. E, conidia anastomosing and germinating on water surface . G, ontogeny . H, turgid non-viable conidium.

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germinating on water or isolation medium, but Flabellospora acuminata Descals sp.nov. (F igs erratically. 5,6,25,26). (Etym.: refers to strongly po inted Conidia of this fungus have con sistently been conidial branch apices ) detected in foam in Ingold's various publications Cultura pura ex uno con idio sejuncta, super MA 2 % (Ingold, 1942, 1958, 1959), in our work and that of in conditionibus supradictis. Colonia alba , cremosa in others. They never occur in abundance, but have centro, crevit 8'S cm diam /s mense s, mycelium aerium been reported from various parts of England and absens. Status conidial is in superficie aquae, incolor, Scotland. Frequent isolations from foam have parietibus cellularum tenuibus et levibus . Sporulatio failed . Conidia tend to swell up without producing abundans sed saepe atypica in aqua sterili distillata ad 15° germ tubes. In January 1974, numerous conidia post 10 dies. Conidiophora e hyphis repentibus, apicalia appeared floating on water after a few days ' vel Iateralia , repentia, mononernata, simplicia vel sparsim incubation in a Petri dish containing a piece of ramosa , septa indistincta, 100-1 So x 3-4 JIm , stipes wood. These were then transferred on to various irregulariter infiatus, cum base constricta. 0-(3) bra chia isolation media with and without antibiotic. saepe unilateralia, perpendicularia, curvata, cum base Several cultures were established on CMA and MA constricta. Cellulae conidiogenae apicales , singulares, integratae, pedunculatae et cernuae, cicatrix perangusta. 2 'Yo , one of which sporu lated rather poorly. The Conidia acrog ena, solitaria , ram osa, axis principalis reason for poor germination is not understood; capitarus. y-ro x 4--{i pm(inapice),(4 }-S-{7)brachia,gemeven one-mont h-old cultures failed to fruit when mantia ante liberationern, simultanea, equidistantia, recta , submerged. fusiformia vel aliq uando obcla vata, (30)-7S- 120 x 7-12 The morphology of this fungus is unique among (- i s) lIm , cum apice acum inato, cum 3-10 cellulis, liberata waterborne hyphomycetes in that con idial branch- in isthmo basali geniculate , dispersa singulariter vel in ing is strictly dichotomous. Another interesting paribu s coniunctis, lente germinantia. H olot ypu s e spurna in rivul o pr ope Bettws-y-Coed, observation is the frequent anastomoses between detached conidia or with nearby hyphae (but not Snowdonia National Park (Wales), SH 2803S6, 24 Oct. 1976, De scals (l M l 216342 et Herb. Exeter 3270). Other between apices of the same conidium), while collections: same source , Mar. 1975, Descals (H erb . floating on water. Exeter 3228) and same source, May 1975, Descals (He rb . Drechsler (1937, 1961) has described two similar Exeter 3535). hyphomycetes : Tripo sporina aphanophaga, a nematode parasite from soil, and T . quadridens, a Pur e cultur e from single conidium in MA 2 % at parasite on testaceous rhizopods. There is no type . standard conditions. Colony white, very pale designated for the former, and only iconotype s for creamy near the centre, margin diffuse, regular or the latter, but they are distinct from our fungus. A lobed, growth 8'5 em diam/5 months, aerial mythird specie s, with conidia 20-28 pm long , but celium absent. Sporulation abundant but often with greatly resembling ours in being mostly branched atypical conidia (swollen branches and acicular in a single plane, has been isolated from decaying terminal appendages) on colony slivers partly leaves in Japan and described from pure culture as submerged in sterile distilled water in a Petri dish T. y akuensis Matsushima (1975). Kitz & Embree at 15-18° for 10 days , conidia produced at water (1980), in the United States, recently added further level on surface mycelium, loosely or in aggrecultural data on this fungus, confirming its gations. Conidiophores on mycelial hyphae, apical saprophytism. or lateral, prostrate, mononematous, simple or Trip osporina uredinicola Hohnel (1912), the type sparsely branched, septa indistinct in water, spec ies, is a parasite of a Puccinia on Derris with 100--15° x 3-4 pm, irregularly swollen, delicate, simple, bent conidiophores and thick-walled apical base abruptly constricted, branches 0-(3), irreguconidia described as hyaline-subhyaline, with an larly distributed or unilateral, perpendicular, obconical main body bearing 3-5, often paired, curved, base abruptly constricted. Conidiogenous lobe s at the apex. It has been redescribed by cells apical, integrated, monoblastic, pedunculate Deighton & Pirozynski (1972) from type material. and drooping, detachment scar ver y narrow. Subramanian (1977) revised the genus, and Conidia aerogenous, solitary, staurosporous, main established T . quadridens as the type of his new bod y clavate, apex capitate, 4-6 /-lm diam, base genus Dwayaangam . Our species is most closely pedunculate, 5-10 pm long, branches (4)-5-(7), budding out before release, synchronous, related to the latter. We also believe that T . y akuensis should be transferred to Dwayaangam, (3° )-75- 120 x 7-12 (- 15) pm, one branch apical, the rest radiating slightly retrorsely, straight, fuspurely on morphogenetic grounds . Parasitism has iform (--obclavate), apex greatly extended, cells not been tested in either species but, in an y case, 3-10, released at a strangulation at the base, dispwe do not regard thi s character as having generic significance. ersed singly or as interlocked pairs, germination erratic on isolation medium.

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:t

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B: lao Mill

Fig. 5. Flabel/ospora acuminata (pure culture). A-G, R-T, Herb. Exeter 3535: ontogeny and proliferation. A-I, K, M, N, conidium development. J, L, 0, R, S, T, various types of conidiophore branching. P, Q, IMI 216342 and Herb. Exeter 3270. P, two detached conidia interlocked as single propagule. Q, branched conidiophore. (A-N, R-S drawn to scale A, remainder to scale B.)

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Fig. 6. Flabellospora acuminate (pure culture). Detached conidia. A-F, Herb. Exeter 3535. F, basal germ tube. G-J, IMI 216342 and Herb. Exeter 3270.

Aquatic hyphomycetes. III This species occurs regularly in foam samples in Great Britain (Ingold, 1975, and our work). Archer & Willoughby (1969) briefly described it from material on submerged wood in a stream in Cumbria, but attempts at isolating it failed. On wood it sporulated basically as on our agar culture, but with simple conidiophores. Conidial branches frequently grew at different rates, probably because of unsatisfactory incubation conditions. This was also noticed in our isolates. During our survey, numerous conidia were isolated. Unlike Dwayaangam cornuta Descals, they frequently produced incipient germ tubes but at a very slow rate. This is due to low viability because, on three occasions, under the same germination conditions, the fungus grew successfully on the isolation medium and then on MA 2 %, on which it sporulated, sometimes abundantly. Conidial morphology is frequently abnormal, with undeveloped clavate branches. Nevertheless, the description from pure culture shows some interesting features. Conidiophores show a peculiar, one-sided type of branching perpendicular to the main body. Conidiogenous cells are apparently determinate, although in some cases arrangements could be interpreted as the consequence of sympodial proliferation. Direct observation of ontogeny should clarify this matter. Conidial release is not well understood. The distinct constriction at the base of the pedunculate primary body could be a collapsed separating cell. Dispersal is also unusual in that neighbouring conidia on the same conidiophore will grow more or less simultaneously, interlocking their branches. The capitate primary bodies may appear so closely interlocked that one could easily interpret re-armed or i z-armed propagules as single conidia. It is interesting to speculate on the survival value of multiple propagules (frequently seen in species of other genera too, such as Dendrospora, Varicosporium and Tricladium) in anchorage and substrate colonization. The conidia of F. crassa Alasoadura (1968a), the type species, described from Nigeria on submerged Phoenix leaflets, are smaller and the branches are not acuminate. Flabellospora verticillata Alasoadura (1968b) has conidia with up to 16 arms oriented antrorsely and spanning up to 270 pm. Flabellospora multiradiata Nawawi (1976) is also closely related. Flabellospora tetracladia Nawawi (1973) has been grown in pure culture. It seems to be an intermediate between Isthmotricladia and other related forms (see discussion on I. britannica). The conidiophores are erect, without an apical constriction, and the primary body of the conidium is much more prominent and never tail-like. Flabellospora amphibia (Price & Talbot, 1966) Descals (see below) is also distinct from our species.

Flabellospora amphibia (Price & Talbot) Descals comb.nov. (Figs 7, 27, 28) Tetracrium amphibium Price & Talbot, Austral. J. Bot. 14: 20-21 (19 66). Sporodochium effuse, very shallow, white or yellowish, up to 2 em diam. Conidiophores lateral, mononematous, sinuous or geniculate, delicate, cylindrical to irregularly swollen, base abruptly constricted, 40-70 x 2-5'5 pm, cells few, often indistinct. Conidiogenous cells apical, single, integrated, monoblastic, detachment scars indistinct. Conidia solitary, apical, staurosporous, septa often indistinct, main body sinuous, delicate, obconical, apex capitate to obconical, 5-7' 5 pm diam, base pedunculate, 6-14 pm long, cells 1-2, branches (4)-5-(6) budding out before release, synchronous, one branch apical, the rest radiating antrorsely, straight or slightly curved, irregularly fusiform, 70-100 x 6-8 pm, multicellular, colourless, vacuolate, released at a geniculation, aggregating in a gloeoid mass. Specimens examined,' Waite Agr. Res. lnst. 15843 (holotype), Eucalyptus bark, National Park, South Australia, July 1966, 1. Price; and 16335 (syntype) on decorticated wood, loc. cit. July 1966, 1. Price.

Tetracrium amphibium Price & Talbot (1966) was described as a terrestrial fungus forming effuse, non-stromatic sporodochia on Eucalyptus wood and bark. Conidiophores are simple, and conidia composed of a small main body and (3)-5-8 fusoid, septate branches. They are released by breakage at a 'geniculate basal septum'. It was not grown in pure culture and there are no later reports. The holotype was examined and the fungus is here described and illustrated, as it bears great resemblance to F. acuminata. The distinguishing features are the presence of a geniculation at the point of detachment and the sinuous conidial branches. Tetracrium aurantii Hennings (1902), the type species, is probably an entomophagous organism, sporulating on 'caespituli' (sporodochia). The 'conidiophores " obviously the primary body of the conidia, are erect, short, subclavate, and nonseptate, and the four' conidia' or apical branches, are fusoid and multiseptate. Hohnel (1911) reexamined the holotype, redescribed the sporodochia as plectenchymatous with a parenchymatous rind, and interpreted the conidia as staurosporous with a short obconical main body and apical elongated branches. The cell walls were described as thick. Petch (1921) associated this fungus with a Podoneetria and described brown sporodochia. The fungus does not appear to have been grown in pure culture, and there are no illustrations of the holotype. Tetrccrium echinatum Perch and T. cocci-

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Fig. 7. Flabe/lospora amphibia (holotype ). A-V, conidiophore morphology and conidial ontogeny; W-Z, detached conidia. (A- V drawn to scale A, W-Z to scale B.)

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Fig. 8. A-E', Isthmotricladia britannica (pure culture, 1M1 216346). A-V, ontogeny and proliferation. A'-F', detached conidia. X, detached conidium from nature. F', I.laeensis (Malaysian isolate, Nawawi, Herb. Exeter 3337). Detached conidium.

E. Descals and cola Hohnel also form dark sporodochia. 'Tetracrium' puttemansii Arnaud (1952), with cruciate conidia, and T. incarnatum Martin (1948), with digitate arms arising from different levels, should probably be transferred to different genera. The taxonomy of staurosporous hyperparasitic hyphomycetes needs revision, but it seems quite evident that T. amphibium is much more closely related in its substrate requirements and morphology to Flabellospora, and we therefore propose its redisposition.

Isthmotricladia britannica Descals sp.nov. (Figs 8, 23, 24). (Etym.: contrasts type locality with those of the other two species) Cultura pura ex uno conidio sejuncta, super MA 2 %, in conditionibus supradictis. Colonia pallida canobrunnea, crevit 8'5 em diam/j S hebdomades, mycelium aerium album, farinosum. Status conidialis aquaticus, incolor, cum parietibus cellularum levibus et tenuibus. Sporulatio abundans in colonia aetatis 10 mensium in aqua distillatasteriliad 15-18° post 10 dies. Conidiophora e hyphis juvenilibus repentibus, micronemata. Cellulae conidiogenae singulares, (3)-6--18 x 1-2 flm, monoblasticae, cicatrices distinctae, proliferationes sympodiales, rhachilliformes. Conidia solitaria, acrogena, staurospora, axis principalis rectus, clavatus, 21-27 x 2'5-3'5 usn, (1)-3-(6) cellulae, cicatrix lata, (3)-4 brachia coronata, simul gemmantia, fusiformia, (24)-35-42 x 2'5-3'5 flm, (3)-7-(9) cellulae, liberata e dissolutione septi basalis, plerumque natantia, facile germinantia. Holotypus e ramunculo coniferalis putrescente, submerso in rivulo in Quantocks, Somerset, 8 Sept. 1974, Descals (lMl 216346 et Herb. Exeter 3276). Pure culture from single conidium on MA 2 % at standard conditions. Colony pale greyish brown, margin diffuse, surface radially convoluted, growth 8'5 em diam/j S weeks, aerial mycelium white, mealy. Sporulation abundant (conidia smaller than in field material) on ro-month-old colony slivers partly submerged in a Petri dish at 15-18° for 10 days on new hypha I growth, near the surface. Conidiophores micronematous. Conidiogenous cells lateral, single, discrete, monoblastic, straight, (3)-6-18 x 1-2 pm, detachment scar apical, proliferations, sympodial, rachis-like. Conidia solitary aerogenous, staurosporous, main body straight, slightly clavate, 21-27 x 2'5-3'5 flm, cells (1)3-(6), detachment scar broad, branches (3)-4, coronate, budding out before release, synchronous, antrorse at a narrow angle, straight or slightly pendulous near the base, fusiform, apex acute, (24)-35-4 2 x 2'5-3'5 psix, cells (3)-7-(9), released at a basal septum.

This species has occasionally been seen in our surveys. Its habitat and substrate are unknown. Conidia strongly resemble those of Isthmotri-

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cladia laeensis Matsushima (1971), the type species, a saprophyte on coconut leaves, apparently of terrestrial occurrence, described from pure culture. The main difference is in the number of arms, typically 4 in our species, whereas I. laeensis only has 3, and these diverge more broadly and are decumbent. We have examined material cultured by Nawawi (Herb. Exeter 3337) and there is little doubt that our fungus is very closely related in ontogeny. There are two other genera with similar forms: Prismaria Preuss and Clavariopsis Ingold. Prismaria alba Preuss (1851), the type species, was originally described on alder bark. It has an effuse sporodochium. Conidial branches were interpreted as individual conidia arranged 'digitately' in groups of 4, on simple, erect, clavate "conidiophores " actually the conidial main body. The conidia appear to be sessile, or nearly so, on micronematous conidiophores. The holotype, if available, has not been re-examined. Only a stylized drawing of a single conidium has been published (Rabenhorst, 1907), and there are no measurements. But considering the aquatic habitat of alders, and the striking similarity in conidial structure with those of Isthmotricladia, they may eventually be placed in synonymy, Prismaria taking precedence as it is an older genus. Pi furcata Grove (1884) is of similar ontogeny, but the conidial branches are 60-100 flm long. Prismaria subtilissima Oudemans, as described in Rabenhorst (1907), has 4-6 clavate to lanceolate conidial branches radiating from an erect, cylindrical main body. Conidia are very small, about 12-13 flm. Both species need redescribing and illustrating. In Claoariopsis aquatica de Wildeman (1895) the coronate arrangement and simultaneous appearance of conidial branches are similar to those in I. britannica, but the conidiophore habit and proliferation of conidia are very different. There are species in Fumagopsis (F. triglyphioides Spegazzini, 1911) Tricornispora (T. bambusae Bonar, 1967), Tridentaria (T. tylota Drechsler, 1964) and Flabellospora (F. tetracladia Nawawi, 1973), as well as an undescribed species of 'Clavariopsis' (Nawawi, unpubl.), which have characters merging with Isthmotricladia, and which should be considered in a future revision.

Tricladiopsis

Descals gen. nov. (Etym.: Tricladium-like) Hyphomycetes dematiacei. Conidiophora plerumque lateralia, mononemata, singularia vel sparsim ramosa. Cellulae conidiogenae apicales, integratae, cum cicatricibus distinctis, cum proliferationibus sympodialibus, rhachilliformibus. Conidia solitaria, acrogena, incoloria, cum parietibus levibus et tenuibus, multiseptata, staurospora, axis principalis elongatus, plerumque cum 2 MYC

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Aquatic hyphomycetes. III

brach iis lateralibus, singularibus, seriatim crescent ibus, cum isthmis basalibus , liberata dissolut ione septi basali. Species typica Tricladiopsis foli osa Descals.

Dematiaceous hyphomycetes. Conidiophores macronematous, mononematous, brown, simple or sparsely branched. Conidiogenous cellsmonoblastic, apical, integrated, detachment scars distinct, proliferations rachis-like, sympodial. Conidia solitary, aerogenous, colourless, multiseptate, staurosporous, released at a basal septum, main body elongate, branches lateral , single, in succession, with basal constrictions. Tricladiopsis foliosa Descals sp.nov . (F igs 9, 29). (Etym.: foliosa : leaf-like appearance of conidial branches) Cultura pura ex uno conidio sejuncta, super MA 2 %, in conditionibus supradictis . Colonia nigra cum alba margine, irregulariter lobata, lente crescit, mycelium aerium abundans, gossypinum. Sporulatio aeria vel aquatica, abundans, e mycelio juvenili in aqua distillata sterili post 7 dies. Conidiophora e hyphis repentibus, plerumque lateralia, perpendicularia, mononemata, brunnea, 44-77 x 3'5- 7'5 11m, cum parietibus levibus et crassis et septis crassis, simplic ia vel sparsim ramosa, stipes rectus , uni vel paucicellularis. Cellulae conidiogenae apicales, integratae, cicatr ices distinctae, cum una vel pluribus proliferationibus sympodialibus rhachilliformibus. Conidia solitaria , acrogena , incoloria , cum parietibus levibus, axis principalis elongatus , constrictus ad insertiones brachiorum, 77- 145 x 4-5 11m, cum apice acuto, multicellularis, cum cicatrice lata, (1}-2-(3) brachia lateralia, seriatim gemmantia, singulariter, parum decumbentia , elongata , cum apice acuto , isthmus basalis levis et sinuosus, 50-100 x 4-5 11m, liberata e dissolut ione sept i basalis, facile germinantia. Holot ypus e spurna in flumine Dart , Dartmeet, Devon, Anglia, 9 Mar . 1975, Descals (l M I 254855 et Herb. Exeter 3532). Isot ypi: e spuma in flumine BarIe, Withypool, Exmoor, Anglia, 28 Apr. 1974, Webster & Descals (H erb. Exeter 3521), e spuma in rivulo prope Bettws-y-Coed, Snowdonia Nat ional Park (SH 280356 ), Wales, 15 May 1976, Descals (Herb. Exeter 3540 ).

Pure culture from single conidium on MA 2 % at standard conditions. Colony black, margin white, irregularly lobed, growth restricted, aerial mycelium abundant, cottony, greyish. Sporulation on young mycelium growing underwater, or also on colony slivers partiy submerged in sterile distilled water in Petri dish for 7 days, conidia produced on exposed surfaces, in small patches. Conidiophores on mycelial hyphae, lateral, at broad angles, (or apical), rnacronematous, mononematous, 4477 x 3' 5-7' 5 tun, brown, cell walls and septa thick, simple or sparsely branched, main axis straight, cells 1 to few, branches diverging at broad angles. Conidiogenous cellssingle, apical, integrated, monoblastic , detachment scars distinct, proliferations

1 to several, sympodial, rach is-like. Conidia solitary, aerogenous, colourless, staurosporous, walls th in, main body slightly curved, smoothly constricted at branch insertions, 77-145 x 4-5 11m, proximal part cylindrical to slightly clavate, distal part fusoid, apex acute , multicellular, detachment scar distinct, branches (1)-2-(3), lateral, budding out before release at different levels and progressively near the developing apex, antrorse at acute angles and slightl y decumbent, narrow-fusoid or obclavate, apex acute, basal constriction smooth and sinuous, 50-100 x 4-5 pm, released at a basal septum.

Conidia of this fungus have been seen sporadically and they may have been confused with those of Sympodiocladium frondosum Descals. The basic difference in conidial branching order did not become apparent until they were critically examined. A reliable character to separate them is that in the latter, the main body is strongly bent at the branch insertion, while in T. foliosa it is only bent at the level of the distal branch. This fungus is of unknown habitat. Though appearing in foam samples, in pure culture it sporulates only above water level. It has been recorded by Ingold (1975) from stream foam in Wales and N.W. Scotland. The erection of a new genus to accommodate this fungu s seems justified . The fungus isa dematiaceous hyphomycete, with mostly dark thick-walled conidiophores, proliferating sympodially in a rachis-like fashion. The conidia displa y Tricladiumlike branching. Such a combination of characters is not found in any other described hyphornycete, except possibl y in Ramulispora sorghi (Ell. & Ev.) Olive & Lefebvre (in Olive et al., 1946), a leaf parasite of Sorghum. Cercospora bromi Sprague (1937) is another plant parasite with apparently similar ontogeny, though the conid ia have a single lateral arm . Newhall (1946) transferred the name to Ramulispora. These two fungi show some similarities to Tricladiopsis, and may eventually be redisposed in it. Tricladiopsis flagelliformis Descals sp.nov. (F igs 10, 11,32-34). (Etyrn.: refers to whip-like appearance of conidial main body) Cultura pura super MA 2 % in conditionibus supradictis . Colonia cum centro nigro, mycelium aerium album et abundans, lente crescit. Stromata dispersa , nigra, pseudoparenchymatosa, usque ad l ' 5 mm diam, findentia stellatim, sterilia . Hyphopodia congregata , lobata et fusca. Status conidial is pallide brunneus, cum parietibus cellularum levibus et tenuibus. Sporulatio abundans in superficie aquae e hyphis repentibus in aqua distillata sterili ad 15-18° post paucos dies. Conidiophora lateralia, rnononernata, simplicia vel sparsim ramosa, brevia, cum 1 - paucis cellulis. Cellulae conidiogenae apicales,

E. Descals and J. Webster

Fig. 9. Tricladiopsis [oliosa (pure culture, IMl 254855 and Herb. Exeter 3532). A-L, oncogeny and proliferation; M-W, detached conidia. 0, P, R, S, T , U, W, typical conidia. (A- K to scale A; L-W to scale B. Scale A, 501lm; scale B, 100 pm .)

420

Aquatic hyphomycetes. III

Fig. 10. Tricladiopsis flagelliformis (pure culture, IMI 216348 and Herb. Exeter 3272). B-K, M-S, ontogeny and proliferation. A, germination by repetition. L, hyphopodia. T -G', detached conidia. (L drawn to scale A; remainder to scale B. Scale A, 50 ~m; scale B, 100,um.)

E. Descals and J. Webster

421

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integratae, incolores, cum cicatrice distincta, proliferationes numerosae, sympodiales, rhachilliformes. Conidia solitaria, acrogena, staurospora, axis principalis angustus, fusiformis, parum curvatus, cum 12-19 cellulis, (65)-10cr{135) x 2-3'5 /lmcumapiceacuto, saepe curvatus flagelliformis, cum cicatrice plana, (0)-1-(2) brachia dorsalia, seriatim crescentia, paene perpendicularia, recta, cylindracea vel parum obclavata, (25)-45-(60) x 2-2'5 tun, isthmi basales saepe curvati, (1 )-pauci cellularia, liberatio e dissolutione septi basalis, natantia, facile germinantia. Conidia secundaria aliquando e cellulis conidiogenis brevibus. Holotypus e folia Querci in rivulo e Cwm Bychan, Snowdonia National Park, Wales, 17 May 1976, L. Hawker (lMl 216348 et Herb. Exeter 3272). lsotypus e spuma in rivulo prope Bettws-y-Coed, Snowdonia National Park (SH 280356), Wales, 17 May 1976, Desca!s (Herb. Exeter 3485).

Pure culture from ascospores of Coccomyces sp. on MA 2 % at standard conditions. Colony black in the centre, growth 7 ern diarny ro weeks, aerial my-

celium white, abundant and lanose. Stromata scattered, black, pseudoparenchymatous, up to t : 5 mm diam immersed or erumpent, splitting stellately but without asci after 2 months' incubation at 10°. Hyphopodia on dark hyphae, lateral, in clusters, lobed, dark, walls thick. Sporulation abundant on 4-month-old colony slivers partly submerged in sterile distilled water in a Petri dish at 15-18° for a few days, conidia produced at water level. Conidiophores on dark hyphae, lateral, macronematous, mononematous, simple or sparsely branched, often geniculate, fuscous, cells one to few, stalk erect, branches irregularly distributed, in random sequence, diverging at broad angles. Conidiogenous cells apical, integrated, monoblastic, colourless, detachment scar flat and narrow, proliferations numerous, sympodial, more or less rachis-like. Conidia solitary, aerogenous, staurosporous, first colourless, later fuscous, main body slightly curved, narrow-fusiform, 13-20 septate,

422

Aquatic hyphomycetes. III

(65)-100-( 135) )( 2-3 '5 ,urn, apex attenuate and bent more or less whip-like, multicellular, detachment scar flat and narrow, branches (0)-1-(2), appearing before releas e, dorsal, diverging at broad angles, straight, cylind rical to slightly obclavate, (25)-45-(60) x 2-3'5 ,urn, basal constriction (if present) slight and bent, cells 1 to few, released at a basal septum. Secondary conidia may appear on short, lateral conidiogenous cells. This fungus has been seen occasionally in foam in North Wales and the Lake District (Cum bria, England). In March 1978, conidia were detected on moist-incubated decaying leaves from the shore-line of Windermere. The distal conidial branch is frequently missing in our pure cultures, but those from field material bear it. They are easily distinguished from those of T.foliosa Descals. The branches in the latter are fusoid and decumbent, while in T. fiagelliformis they are straight and cylindrical. The distal part of the main body in T. foliosa mimics the lateral branches, while in T. fiagelliformis it is thin and curved, lash-like. Unbranched conidia, also present in pure culture, resemble Cercospora and related genera. The Coccomy ces from which our holotype was derived has been tentatively identified as C. dentatus (K unze & Schmidt) Sacc owhich is known to occur in Great Britain on Qu ercus leaves (D enn is, 1968 ). The ascocarps were about 1 mm diam, outer wall shiny black, open ing stellately, exposing a white centrum. The asci were clavate, with a conical apex and broadened stalk, measuring 60-102 x 7' 2- 8"7 ,urn. The eight ascospores were clavate, with a pointed base, unicellular, 48-62 x 1'2-2 ,urn. The paraphyses were clavate , 55-65 x 2'5-3 11m. It is interesting that Stoianovic & Boric (1974) associate Coccomy ces hiemalis Higgins with S eptoria padi ( = Phloe osporella padi (Li b.) von Arx ), a Coelomycete with conidial morphology and ontogeny somewhat resembling Tricladiopsis fiageliformis, except for the lack of branching.

Scorpiosporium rangiferinum Descals sp.nov. (Figs 12, 13, 21). (E tyrn . : rangifer : antler-like conidia) Cultura pura de uno conidio sejuncta, super MA 2 % in conditionibus supradictis , Colonia brunnea, lente crescit, mycelium aerium velutinum, brunneum, hyphae cum excrescentiis fuscis verruciformibus, ad 25 pm diam, saepeconfertirnaggregatae. Status conidialisincolor, cum parietibus cellularum levibus et tenuibus. Sporulatio aquatica, modica in aqua distillatasterili ad 15-18° post 5 dies. Conidiophora e hyphis repentibus, repentia, mononernata, gregaria,recta, multicellularia, simplicia. Cellulae conidiogenae apicales, integratae. Conidia acrogena, solitaria, quorum spithama ad 550 !tm, irregulariter brachiata, axis principalis elongatus, geniculatus ad

insertiones bracchiorum, usque ad 450 x 3'5-5 11m, multicellularis, apex acutus, cicatrices planae, brachia lateralia, singularia(vel bina) raro verticillata, in tribus d imen sionibus, recta (vel parum curvata prope basim), apex acutus, basis lata, multicellularia, ( 1}-4-(7) brachia primaria, bracchiasecundaria aliquando adsunt, liberatio e dissolutione septi basalis, facile germinantia. Status phialidicus adest in eisdem conditionibus, aquaticus, incolor, cum parietibus cellularum levibus et tenuibus. Sporophora e hyphis repentibus aut e brachiis conidiorum Scorpiosporii status, repentia, mononernata, ramosa, multicellularia, stipes tenuis, usque ad 600 x 4-6 !t m , brachia singularia, 10-20 x 2'5-3 '5 pm, rnetulae in seriebus singularibus vel triplicibus, penicillatae, moniliforme (vel cylindraceae), 6-10 x 3 x 5 11m. Cellulaesporogenae phialidicae,apicales, (singulares) vel penicillatae, fusoideae vel ellipticae, 6-12 x 3-4 pm, collum cylindraceum, 5-7'5 x 1'7-2 '5 p.m, cum basi abrupte con stricto, Phialosporaenon-septatae, elongatae, 5-7 x 2 pm, aut globosae, t : 5-2 Jim diam, cicatrices distinctae, in agglomerationibus viscosis, germinatio non visa. Holotypus e spuma in rivulo Caudale, Cumbria (NY 401115 ), May 1974, Webster & Descals (IMl 254852 et Herb. Exeter 3526). Pure cult ure from single conidium on MA 2 % at standard conditions . Colony brown, margin paler and diffuse, growth slow, aerial mycelium felty and brown, raised near the centre. Wart-like protuberances dark, single and large (25 /1m diam), or smaller and in dense aggregations, on dark hyphae. Sporulation moderate on y-monrh-old colony slivers partly submerged in sterile distilled water at 15-18° for 5 day s. Conidia produced on cut surfaces in moderately dense aggregations, underwater, interspersed with the spermatial state. Conidiophores on mycelial hyphae, apical, mononernatous, gregarious, pro strate, cylindrical, multicellular. Conidiogenous cells apical , monoblastic, int egrated . Conidia solitary, staurosporous, aerogenous, spanning up to 550,um, main body geniculate at branch insertion s, cylindrical, up to 450 x 3'5-5 ,urn, apex acute, detachment scar broad and flat, branches lateral, arising before release, singly (or in pairs), seldom in verticils of 3, at variable levels, progressively in several planes, antrorse at broad angles or perpendicular, straight (to slightly curved near the base), apex conical, base broad, multicellular, primary branches (1)-4-(7), secondary branches sometimes present, relea sed readily at a basal septum, dispersed singly or in tangled clusters underwater, germinating readily on isolation medium . Ph ialidic sta te produced simultaneously, colourless, aquatic. Conidiophores on mycelial hyphae or macroconidial branches, apical or lateral, mononematous, prostrate, branched, main body cylindr ical, delicate, 600 x 4-6 ,urn, branches lateral, single , loosely arranged, cylindrical, 10-20 x

E. Descals and J. Webster

Fig. 12. Scorpiosporium rangiferinum and phialidic state (pure culture, 1M1 254852 and Herb. Exeter 3526). A, ontogeny of conidia; B, wart-like protuberances on dark hyphae, C-D, phialidic state. C, habit drawing; D, sporophores. (A to scale A; Band D to scale B. Scale A, 100 p,m; scale B, 50 p,m.)

Aquatic hyphomycetes. III

Fig. 13. A-E, Scorpiosporium rangiferinum: detached conidia and phialidic state (same material as Fig. 12). F-G, Scorpiosporium sp. (Herb. Exeter 3522). Mature detached conidia. (A-D and F, G to scale A; E to scale B. Scale A, 500 /lm; scale B, 250/lm.) (Dotted lines indicate germ tubes.)

E. Descals and 2'5-3'5 flm, metulae in (1)-3 series, penicillate, cells moniliform (to cylindrical), 6-10 x 3-5 flm. Sporogenous cells phialidic, apical, (single) to penicillate, fusoid-elliptical, 6-12 x 3-4 flm, collarette cylindrical, 5-7'5 x 1'7-2'5 /1m, base abruptly constricted. Phialospores non-septate, first conidium elongated, 5-7 x 2 flm, subsequent conidia globular, t : 5-2 flm diam, detachment scars distinct, aggregating in gloeoid masses, germination not seen. Conidia of these dimensions and configuration have not been reported elsewhere, although there is a slight possibility that the fungus may be the same as Tricladium anomalum Ingold (1943), for which there is no type designated, which was probably described from sparse field material not containing the more complex types of branching seen in our isolate. The distribution of S. rangijerinum is probably limited to moorland habitats. Conidia have never been detected in foam samples other than the original. Their identification is difficult as they are structurally identical to those of a slightly different species (Herb. Exeter 3522), but with normally larger conidia (Fig. 15 F , G), and also may resemble abnormal forms of Tricladium giganteum Iqbal (1971) as well as of Polycladium equiseti Ingold (1959)· Our species generally fits the characters of Scorpiosporium Iqbal. Scorpiosporium minutum Iqbal (1974), the type species, resembles S. rangijerinum in its habitat, dark pigmentation in pure culture, simple conidiophores and apical conidia with 2-3 lateral branches appearing singly and progressively. Secondary laterals appear infrequently. The conidiogenous cells are likewise determinate. SCORPIOSPORIUM sp. Exeter 3522 (Figs 13, 35). This is a similar fungus isolated from decaying submerged monocotyledonous leaves along the shores of Malham Tarn, near Settle, Yorkshire. It produces a dark colony and sporulates profusely underwater with conidia spanning up to 1300 flm, roughly three times the size of those of S. rangiferinum, and probably the largest ever recorded from nature. They are formed acropleurogenously on what appear to be simple conidiophores. Microscope slides have been prepared but more studies are needed for a formal description.

Sigmoidea aurantiaca Descals sp.nov. (Figs 14, 30). (Etyrn.: refers to orange colony pigmentation on MA 2 %) Cultura pura ex uno conidio sejuncta, super MA 2 '/0' in conditionibus supradictis. Colonia aurantiaca, crevit 6 em diamy i S hebdomades, superficies radiatim convo-

J. Webster

425

luta, findens in centro, mycelium aerium farinosum, album. Protoperithecia fusca. Status conidialis incolor, cum parietibus cellularumlevibuset tenuibus. Sporulatio aeria abundans aut aquatica. Conidiophora mononemata, gregaria, interdum caespitosa, 24-60 x 2'5-5'5 /fm, simplicia vel sparse brachiata, recta vel curvata, uni-vel paucicellularia. Cellulaeconidiogenae apicales,discretae, irregulariter inflatae, cicatrices saepe denticulatae, proliferationes abundantes, sympodiales, rhachilliformes, Conidia acrogena, recta, postea falcata vel helicoidea, ad 90 x 3'5-4'5 /fm, (1)-6-(10) cellulae cum parietibus levibus et tenuibus, cicatricesplanae, liberatio e dissolutione septi basalis, facile germinantia. Holotypus e ramunculo decorticato in rivulo Smooth, prope Hawkshead, Cumbria, Anglia (SD 361975), 23 Apr. 1976, Descals (IMI 216343 et Herb. Exeter 3271). Isotypi: Herb. Exeter 3538, 3539. Pure culture from single conidium on MA 2 % at standard conditions. Colony orange, surface radially convoluted and cracking in the centre, margin paler, 1 cm wide, growth 6 cm diam/18 weeks, restricted, aerial mycelium sparse, powdery, white near the centre. Protoperithecia abundant, dark, on surface mycelium and immersed. Sporulation very abundant on colony slivers partly submerged in sterile distilled water in a Petri dish at 15-18° for 2 days, underwater or on exposed surface mycelium. Conidiophores on hyphal coils, mycelial hyphae or torulose cells, macronematous, mononematous, in dense aggregations, sometimes caespitose, 24-60 x 2'5-5'5 flm, simple or sparsely branched, cells 1 to few, main body cylindrical, branches perpendicular or antrorse, straight or irregularly curved, cells 1 to few. Conidiogenous cells single, apical, discrete, monoblastic, irregularly swollen (or obclavate), apex attenuate to denticulate, detachment scar flat, with 10 or more sympodial proliferations arranged rachis-like. Conidia aerogenous, straight but later falcate, sigmoid or in an extended helix, up to 90 x 3' 5-4' 5 flm, cells (1)-6-(10), detachment scar flat, released at a basal septum, dispersed singly in or on water, germinating readily on isolation medium. The conidia of this lignicolous fungus resemble those of Flagellospora penicillioides Ingold (1944), but are not produced on phialides. They are also distinct from Anguillospora in that proliferation is sympodial and rachis-like. Scolecosporous conidia are also present in Filosporella Nawawi, but here the conidiophores have penicillate heads. Mycocentrospora acerina (Hartig) Deighton (1972) has syrnpodial proliferations, but detatchment scars are broad and conidia often bear a caudal branch, never present in S. aurantiaca. Anguillospora prolifera Petersen (1963), the type species of Sigmoidea, was described as phialidic or aleuriosporic. Ampulliform conidiogenous cells are produced on very short lateral conidiophores and

426

Aquatic hyphomycetes. III

B

= ..;> ..

Vl

_0 0;:

03 . 3

1:

Fig. 14. Sigmoidea auranriaca (pure culture, IMI 216343). A-J, M, o-U, ontogeny . K, repetitive germination. L, N, sporulation on hyphal coils. V : detached conidia . (A-T to scale A; U and V figures to scale B.)

E. Descals and proliferate sympodially on one or more rachis-like extensions. The conidia are curved and nonseptate, and are produced underwater and aeriall y. Dark pigments are not formed on OMA. Crane (1968) described an isolate producing brown pigments on an unspecified medium. Dark ' chlamydospores' were also present. Multiseptate conidia of similar dimensions were produced on ' lateral phialides, or aleuriophores or sympodulae. ' Ne vertheless, it was considered conspecific with Petersen's fungus, and redisposed in a new genus, Sigmoidea Crane, characterized by ' lateral phialides bearing multiseptate eel-like conidia.' Other types of proliferation are not included in the formal description. Sigmoidea aurantiaca pr oduces very similar sympodial extensions, and successive conidia do not appear to be formed on the same locus. Annellations are not evident in any of these fungi. We believe that our species is closely related to Sigmoidea prolifera. In order to be included in this genus, its diagnosis should be emended to specify sympodial proliferation instead of phialidic. The term polyphialide is used by some for structures such as those in Sigmoidea. But a phialide by definition should show successive proliferation Oil at least one locus. This has not been demonstrated in Sigmoidea.

Sporidesmium ensiforme Descals sp.nov. (Figs 15,38). (Etyrn.: ensiforme: sword-like, straight, referring to conidial shape) Cultura pura ex uno conidio sejuncta, super MA 2 %, in conditionibus supradictis, Colonia brunnea, moderate crevit, mycelium aerium gossypinum, cano-brunneurn, Status conidial is incolor , cum parietibus cellularum levibus et tenuibus. Sporulario abundans in aqua dist illata steril i post paucos dies. Conidiophora e hyphis fuscis, apicalia , mononernata, greg aria, repentia, simplicia, 75-100 x 5-6/tm, cum una vel pauci s cellulis . Cellulae conidiogenae apicales , integratae, 30-33 x 5-6 um , cicatrices Iatae, cum nulli s vel paucis proliferationibus percurrentibus. Con idia solitaria, acrogena, recta vel sinuosa, 700-1300 x 8-9 usn, multicellularia, apices acutae, cicatrices latae, cellulae saepe moniliformes post liberationem, rare cum brachia laterali calcariformi arcte adjuncto ad axem principalem, Iiberatio e dissolutione septi basalis, facile germinantia. Holotypus e spuma in Blea Tarn, Cumbria, Anglia (N Y 294045), 11 May 1974, Webster & Descals (lMI 254856 et Herb. Exeter 3524). Isotypus e spuma in rivulo, Stoke Woods, Exeter, De von, Anglia , 14 Feb. 1974, Descal s (H erb. Exeter 3518).

Pure culture from single conidium on MA 2 % at standard conditions. Colony brown, growth mod erate, aerial mycelium cottony, gre yish-brown . Sporulation abundant on colony slivers submerged in sterile, distilled water in a Petri dish for a few days, conidia produced on cut surfaces, underwater. Conidiophores on dark hyphae, arising through torn

J. Webster

hyphal ends , mononematous, gregarious, prostrate, simple, straight or sinuous, acroauxic, cylindrical, 75-100 x 5-6 usn, cells 1 to few. Conidiogenous cells ap ical, integrated, monoblastic, 30-33 x 5-6 usn, detachment scar broad, proliferations 0 to few, percurrent. Conidia solitary, aerogenous, straight or slightly sinuous, rigid, apex conical, base broad, multicellular, 500-1300 x 8-9 pm, cells often swelling after release, walls thin, spur-like branch rare , lateral, antrorse, closely adpressed to the primary body, released at a basal septum, dispersed singly in water , germinating readily on isolation medium . This fungus, with sword-like conidia longer than those of any other described hyphomycete, has been seen on several occasions, especially in moorland habitats. Its classification is not easy. The conidiophores are colourless but very short, and, in pure culture, arise from the torn ends of dark hyphae on the cut surfaces of submerged agar. They are also very short in nature. The fungus therefore could be considered a dematiaceous species . It could also be classified as an Anguillospora sensu lata: separating cells are not present, but proliferation is percurrent, as in A . longissima and A. crassa. On the other hand the conidium is not characteristically a spiral as those of the latter usuall y are . Anguillospora is being subject to taxonomic revision, and we prefer not to include our species in it . Among the dematiaceous hyphomycetes Ellis (1976) briefly describes Sporidesmium eucaly p ti M. B. Ellis & D. Shaw. Its simple conidiophores can bear up to three percurrent proliferations. Conidia are pale brown and up to 350 pm long. They are also sword-like, and strikingly similar to those of our species, except in the slight pigmentation and thick walls. Sporidesmium Link ex Fr. is based on S . atrum Link (1809). The genus is characterized by dark colonies, macronematous, mononematous, simple and brown conidiophores, integrated, terminal and determinate or percurrent con idiogenous cells, and solitary, dry, aerogenous, simple, straight or curved, or occasionally sigmoid, str aw-coloured or darker and septate conidia (Ellis, 1971 ). Sporidesmium ensiforme differs only in that it probably has gloeospores (most aquatic conidia are sticky). Dispersal is not aerial.

Sympodiocladium Descals gen.nov. (E tyrn. : refer s to sympodial development of conidial branches) H yphorn ycetes . Colonia fusca. Status conidialis incolor, cum parietibus cellularum levibus et tenuibus. Con idiophora micronemata. Cellulae conidiogenae laterales , rare apicales . Conidia solitaria, blastica.rnulticellularia, staurospora , axis principalis elongatus, brachia sympodialia. Species typicus S . frondosum De scals.

Aquatic hyphomycetes. III

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Fig. 15. Sp oridesmium ensiforme (p ure culture, 1M1254856 and Herb. Exeter 3524). A, conidiophores on to' ends of hyphae, with percurrent proliferations. B, habit drawing. C-H, detached conidia. C, E, charact e fragmentation of cells near the base. G, spur-like lateral branch seen occasionally. (A to scale A; B tr C, D, F to scale C; E, G, H to scale D.)

E. Descals and J. Webster Hyphornycetes . Colony dark. Conidiophores rnicronernatous. Conidiogenous cells apical or lateral, discrete, monoblastic. Conidia solitary, holoblastic, multiseptate, staurosporous, with main body and branches elongate and decumbent, the latter arising syrnpodially. Sympodiocladium frondosum Descals sp.nov, (F igs 16, 17,31). (E tyrn. : refers to compact arrangement of leaf-like conidial branches) Cultura pura ex uno conidio sejuncta, super MA 2 %, in conditionibus supradictis, Colonia fusca pu rpurea , crevit 5 em diam/5 menses, pigmentum diffusibile cyano-purpureum, cum superficie rugata , radiatirn lindens, mycelium aerium sparsum, album . Status conidialis incolor, cum parietibus cellularum levibus et tenu ibus. Sporulatio in aqua distillata sterili ad 15-1 8° post 8 dies. Conidiophora rnicronernata, septa indistincta. Cellulaeconidiogenaelaterales,rareapicales,5'5-11 x 1,8-

3'5 pm, ampulliformes

vel cylindraceae, basis lata. Conidia solitaria, acrogena, blastica, staurospora, axis principali s elongatus, leve constrictus et curvatus ad insert iones brachiorum, 37-54 x 2'5-3 '5 I'm, multicellularis, pars remota pendulosa , apex attenuatus, pars proxima recta, cylindracea, basis constricts, ( 1r 2-{3) brachia sympodialiter gemrnantia, dorsalia, in tribus dimensionibus, obclavata, apices acuti, 21-30 x 2'5-3 {1m, multicellularia, basis parum constrictus et pendulus, liberatio ad constrictiones basales, facile gerrn inantio, Holotypus e spuma in ftumine North Teign, Batworthy, prope Chagford, Devon , Aug. 1974, Descals (1M ! 254854 et Herb . Exeter 3528).

Pure culture from single conidium on MA 2 % at standard conditions. Colony dark purple, with bluish purple diffusible pigment, surface convoluted and cracked radially, margin d iffuse, aerial mycelium white and sparse, growth 5 cm diam/s months, restricted. Sporulation aquatic, abundant

Fig . 16. Sympodiocladiumj rondosum (pure culture, 1M! 254854 and Herb. Exeter 3528). A-Q, ontogeny and proliferation. I , numbers indicate branching sequence in 4- and 5-armed conidia . N, conidia budding out (all drawn to scale B). R-T , aggregations of conidiophores near hyphal apices (R and S) or intercalary (T) (habit drawing to scale A). (Scale A, 100 {1m; scale B, 200 {1m.)

43°

Aquatic hyphomycetes. III

Fig. 17. Sympodiocladium frondosum (same material), Detached conidia.

on 7-month-old colony slivers partly submerged in sterile distilled water in a Petri dish at 15-18° for 8 days, on submerged surface hyphae. Conidiophores in loose aggregations, micronematous, often intercalary, septa indistinct. Conidiogenous cells apical or lateral, discrete, monoblastic, ampulliform or cylindrical with apex constricted, 5'5-11 x 1'83'5 pm. Conidia solitary, apical, staurosporous, protoplasm vacuolate, main body initially straight and cylindrical, but smoothly constricted and bending 45-90° at the branch insertion, 37-54 x 2'5-3'5 pm, upper part decumbent, apex attenuate, base abruptly constricted, with up to 11 cells, branches single, in one, two or sometimes three orders, budding out sympodially, in close succession, more or less dorsally on the curvature of the developing parent branch, antrorse at a broad angle, in different planes, straight to slightly sinuous or decumbent, obclavate, apex acute, 21-30 x 2'5-3 pm, with up to 5 cells, basal constriction smooth, released readily at this level,

dispersed singly in water, germinating readily on isolation medium. This species has been isolated once from stream foam in Devon. No other records appear in the literature surveyed. The conidia superficially resemble those of Tricladiopsis foliosa Descals (see above). But the order of appearance of the conidial branches is fundamentally different and very constant. The main body curves strongly and loses its apical dominance as the primary branch appears near its apex. This process is repeated on successive branches. It could be interpreted as a main body bearing a single lateral branch, and this in turn a single secondary lateral. But branching occurs so close to the growing apex that the term sympodial seems most appropriate. In Varicosporium Kegel (1906), Pleuropedium Marvanova & Iqbal (1973) and Gyoerffyella Kol (1928) a somewhat similar pattern of successive branching can be discerned, but the origin of the branches is always well behind the growing point

E. Descals and J. Webster

43 1

Fig. 18. Tricellula botryosa (pure culture, 1M1 254853 and Herb. Exeter 3302). Conidiophores, ontogeny and detached conidia. Bottom right figure: detached conidium from nature.

Aquatic hyphomycetes. III

432

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Figs 19-24, Light micrographs. Fig. 19, Articulospora atra (pure culture, IMI 216359). Conidiophore showing successive development of conidial branches. Fig. 20, A. atra (same material). Polyblastic conidiogenous cells and sympodial proliferation. Fig. 21, Scorpiosporium rangijerinum (pure culture, 1MI 254852). Detached conidium. Fig. 22, Dwayaangam cornuta (pure culture, IMI 216351). Detached conidia floating on water and anastomosing. Two conidia show abnormal branching. Fig. 23, Isthmotricladia britannica (pure culture, IM1 216346). Conidia developing laterally on micronematous conidiophore. Fig. 24, I. britannica (same material). Detached conidium.

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J. Webster

433

~

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27

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25pm

28

26

25

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29

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60 pm

50pm

30

31

Figs 25-31, Light micrographs. Fig. 25, Flabellospora acuminata (pure culture, IMI 216342). Notice pendulous conidiogenous cell. Fig. 26, F. acuminata (pure culture, Herb. Exeter 3228). Detached conidia. Fig. 27, F. amphibia (Holotype). Ontogeny. Notice geniculation. The conidiophore is constricted at the base. Fig. 28, F. amphibia (same material). Detached conidium. Fig. 29, Tricladiopsis foliosa (pure culture, IMI 254855). Ontogeny. Notice sympodial proliferation. The main body of the conidium remains distinct, as opposed to that in Sympodiocladium (Fig. 31). Fig. 30, Sigmoidea aurantiaca (pure culture, Herb. Exeter 3538). Notice rachis-like sympodial proliferations. Fig. 31, Sympodiocladium frondosum (pure culture, IMI 254854). Ontogeny. Notice blowing-out of conidial primordium from a narrow point on the short conidiophore.

434

Aquatic hyphomycetes. III

Figs 32-38, Light micrographs. Fig. 32, Tricladiopsisjlagelliformis (pure culture, 1M1 216348, derived from Coccomyces ascospores). Sympodial proliferation. Notice flat detachment scars. Fig. 33, Ti fiagelliformis (pure culture, Herb. Exeter 3485). Detached conidium. Fig. 34, Coccomyces rdentatus (IM1 216348). Asci and ascospores. Fig. 35, Scorpiosporium sp. (Herb. Exeter 3522). Conidia developing acrogenously on decaying leaf. Notice straight, spine-like arms. Fig. 36, Tricellula botryosa (pure culture, IMl 254853). Conidia develop by a budding-out process. Fig. 37, T. bOlryosa (same material). Detached conidium, showing main body and radiating arms, some germinating. Fig. 38, Sporidesmium ensiforme (pure culture, 1M1 254856). Detached conidia germinating through the detachment scar.

E. Descals and of the subtending arm. The basal constriction of the main axis is also a distinguishable feature of S. frondosum. There is a possibility that the conidiogenous cells might be phialidic. Detachment scars are not distinct. This combination of characters is unique and therefore we believe that the erection of a new genus is justified. Tricellula botryosa Descals sp.nov. (Figs 18, 36, 37). (Etym.: botryosus: grape-like clusters, referring to conidial morphology) Cultura pura ex uno conidio sejuncta, super MA 2 %, in conditionibus supradictis. Colonia cremeo-brunnea vel coffeata, tarde crescit, superficies mucosa, mycelium aerium sparsum, humile, album. Status conidialis incolor, cum parietibus cellularum levibus et tenuibus. Sporulatio abundans in aqua distillata sterili ad 15-18° post 15 dies. Conidiophora lateralia, mononemata repentia, brachiata, cellulae usque ad 50 x 2-3 fLm, moniliformes. Cellulae conidiogenae apicales vel laterales vel intercalares, discretae, inflatae, polyblasticae, cicatrices distinctae, 10-18 x 2-3 fLm. Conidia acropleurogena, staurospora, axis principalis ovoideus vel limoniformis, unicellularis, 8-15 x 3-4 tun, (3)-9-(12) brachia gernrnantia ante liberationem conidiorurn, equidistantia, limoniiformia vel botryosa, apex saepe marnrniformis, basis pedunculata, unicellularia, facile liberata ad constrictionem, 10-13 x 5-9 fLm, facile germinantia. Holotypus e spuma in flumine Lyd, prope Okeharnpton, Devon, Anglia, 8 Feb. 1974, Webster & Descals (lMl 254853 et Herb. Exeter 3302).

Pure culture single-conidium isolate on MA 2 % at standard conditions. Colony creamy brown to coffee-brown, often slimy, margin diffuse, growth slow, aerial mycelium sparse, low and white. Sporulation abundant on agar in sealed Petri dishes and on colony slivers partly submerged in sterile distilled water in a Petri dish at 15-18° for 5 days. Conidiophores on mycelial hyphae, frequently diverging from mycelial strands, lateral, mononematous, prostrate, irregularly shaped, cells moniliformy i to few. Conidiogenous cells mono- or polyblastic, apical, lateral or intercalary, integrated or discrete and ampulliform, detachment scar broad, 10-18 x 2-3 JIm. Conidia solitary or fasciculate, acropleurogenous, distributed irregularly, main body ovoid to limoniform, unicellular, 8-15 x 3-4 ttm, branches (3)-9-(12), budding out in succession before release, equidistant, limoniform to botryose, apex often nipple-like, base often pedunculate, unicellular, sometimes caducous, 10-13 x 5-9 ttm, conidia released readily at the basal constriction, dispersed singly in water, germinating readily on isolation medium. The classification of this species is problematic. Similar conidia occur in Blastobotrys. Blastobotrys nivea Klopotek (1967), the type species, is a soil

J. Webster

435

fungus producing white colonies and simple to branched conidiophores with monilioid cells. The ,conidiogenous cells' are caducous at a basal septum and proliferate sympodially, leaving distinct pedicels. 'Conidia' bud out over the entire surface of the conidiogenous cells. They are round, hyaline, with thick, finely echinulate walls, and are released at a later stage. They can also produce chains of secondary conidia. The fungus has a yeast phase. Blastobotrys aristata Marvanova (1976) was isolated from mouldy plaster. It seems to be a closely related organism. The conidia, though, are smooth-walled. Blastobotrys proliferans Marvanova (1976) produces conidia alternately on hyphae or on conidiophores. Percurrent proliferations can occur. The genus is characterized by the presence of the distinct pedicellate scars, arranged sympodially. In our fungus, there are no such pedicels. Furthermore, the swollen conidial branches do not normally secede from the central body. Vestigiumfelicis Pyrozynski & Shoemaker (1972), a Coelomycete, has superficially similar conidia, but these bear wide-based lobes arranged in a single vertical plane around the swollen main body. Uvarispora Goos & Pirozynski (1975) and Pyramidospora casuarinae Nilsson (1962) have conidia composed of swollen branches surrounding the main body, but the latter is not unicellular. Tricellula van Beverwijk (1954) has similar conidiophore morphology but conidial branching is only apical or subapical. To accommodate our species in this genus would require emending it to include conidial branching from anywhere on the main body. If this is done, the erection of a new genus is unnecessary. Volucrispora ornithomorpha (Trotter) Haskins was recently redescribed from the natural substrate by Hawksworth (1976). Although the conidial branches are much more elongated, this is probably the closest relative of T. botryosa. Our species, though, is placed under Tricellula, following Carmichael et al. (1980).

REFERENCES

ALASOADURA, S. O. (1968a). Flabellospora crassa n.gen., n.sp., an aquatic hyphomycete from Nigeria. Nova Hedwigia 15,415-418. ALASOADURA, S. O. (1968b). Flabellospora uerticillata, a new species of aquatic hyphomycetes from Nigeria. Nova Hedwigia 15, 419-421. ARCHER, J. F. & WILLOUGHBY, L G. (1969). Wood as the growth substratum for a freshwater foam spore. Transactions of the British Mycological Society 53, 484-486. ARNAUD, G. (1952). Mycologie concrete. Genera 1. Bulletin de la Societe mycologique de la France 68,

181-2 23.

Aquatic hyphomycetes. III BEVERWIJK, A. L. VAN (1954). Three new fungi: Helicoon pluriseptatum n.sp., Papulaspora pulmonaria n.sp., and Tricellula inaequalis n.gen., n.sp, Leeuwenhoek nederlandsche Tijdschrift 20, 1-16. BONAR, L. (1967). Studies on Deuteromycetes. Mycologia 59, 596-599· CARMICHAEL, J. W., KENDRICK, W. B., CONNERS, I. L. & SIGLER, L. (198o). Genera ofHyphomycetes. University of Alberta Press, Edmonton. CRANE, J. L. (1968). Freshwater hyphomycetes of the Northern Appalachian highland including New England and three Coastal Plain States. American Journal of Botany 55, 996-1002. DEIGHTON, F. C. (1972). Mycocentrospora, a new name for Centrospora Neerg. Taxon :U, 716. DEIGHTON,F. C.&PIROZYNSKI,K. A.(1972).Microfungi. V. More hyperparasitic hyphomycetes. Mycological Papers 128, 1-110. DENNIS, R. W. G. (1968). British Ascomycetes. Cramer, Lehre. DESCALS, E., WEBSTER, J. & DYKO, B. J. (1977). Taxonomic studies on aquatic hyphomycetes. I. Lemonniera de Wildeman. Transactions of the British Mycological Society 69, 89-109. DRECHSLER, C. (1937). Some hyphomycetes that prey on free-living terricolous nematodes. Mycologia 29, 447-55 2. DRECHSLER, C. (1961). Some clampless hyphomycetes predacious on nematodes and rhizopods. Sydowia 15, 9-25· DRECHSLER, C. (1964). A Tridentaria subsisting on testaceous rhizopods and Pythium oospores. Sydowia 18, 359-363. ELLIS, M. B. (1971). Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew. ELLIS, M. B. (1976). More Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew. Goos, R. D. & PIROZYNSKI, K. A. (1975). Fungi of the Barro Colorado Island; new and interesting hyphomycetes. Canadian Journal of Botany 53, 2927-2932. GROVE, W. B. (1884). New or noteworthy fungi. Journal of Botany (London) 22, 195-201. HANSFORD, C. G. (1946). The foliicolous Ascomycetes. Mycological Papers 15, 1-240. HASKINS, R. H. (1958). Hyphomycetous fungi. Canadian Journal of Microbiology 4, 273-285. HAWKSWORTH, D. L. (1976). New and interesting microfungi from Slapton, South Devonshire: Deuteromycotina III. Transactions of the British Mycological Society 67, 51-59· HENNINGS, P. (1902). Fungi Sao Paulenses La.cl. Puttemans collecti. Hedwigia 41, 116. HOHNEL, F. VON (1911). Fragmente zur Mykologie. Akademie der Wissenschaft, Wien, Mathematik-Natur, Kl. Sitzbericht Abteilung I, 120, 405-408. HOHNEL, F. VON (1912). Fragmente zur Mykologie. XIV. Akademie der Wissenschaft, Wien, Mathematih-Natur, Kl. Sitzbericht Abteilung I, 120, 405-408. INGOLD, C. T. (1942). Aquatic hyphomycetes of decaying alder leaves. Transactions of the British Mycological Society 25, 339-417. INGOLD, C. T. (1943). Further observations on aquatic hyphomycetes of decaying leaves. Transactions of the British Mycological Society 26, 104-115.

INGOLD, C. T. (1944). Some new aquatic hyphornycetes. Transactions of the British Mycological Society 27,35-47. INGOLD, C. T. (1958). Aquatic hyphomycetes from Uganda and Rhodesia. Transactions of the British Mycological Society 41, 109-114. INGOLD, C. T. (1959). Submerged aquatic hyphomycetes. Journal of the Quekett Microscopical Club, Ser. 4, 5, 115-130. INGOLD, C. T. (1975). An illustrated guide to aquatic and waterborne hyphomycetes (Fungi Imperfecti) with notes on their biology. Freshwater Biological Association Scientific Publication 30, 1--<)6. INGOLD, C. T., McDOUGALL, P. J. & DANN, V. (1968). Volucrispora graminea sp.nov. Transactions of the British Mycological Society 51, 325-328. IQBAL, S. H. (1971). New aquatic hyphomycetes. Transactions of the British Mycological Society 56, 343-352. IQBAL, S. H. (1974). Scorpiosporium minutum gen.nov., sp.nov., an aquatic hyphomycete. Biologia 20, 17-21. KEGEL, W. (1906). Varicosporium elodeae, ein Wasserpilz mit auffallender Konidienbildung. Bericht der deutschen Botanischen Gesellschaft 24, 213-216. KITZ, D. J. & EMBREE, R. W. (1980). Growth and sporulation of Triposporina yakuensis. Mycologia 72, 821-825. KLOPOTEK, A. VON (1967). Blastobotrys nivea gen.nov., sp.nov. Archiv fur Mikrobiologie 58, 92--<)6. KOL, E. (1928). Uber die Kryovegetation der HohenTatra, I. Folia Cryptogamica 1, 614-622. LINK, H. F. (1809). Observationes in ordines plantarum naturales. Dissertatio prima. Gesellschaft Naturforschender Freunde zu Berlin, Magazin 3, 4-42. MARTIN, G. W. (1948). Additions to Galapagos fungi. Pacific Science 11, 71-77. MARVANOVA, L. (1976). Two new Blastobotrys species. Transactions of the British Mycological Society 66, 217-222. MARVANOVA, L. (1977). Two new Alatospora species. Archiv der Protistenkunde 119, 68-74. MARVANOVA, L. & IQBAL, S. H. (1973). Pleuropedium tricladioides gen. et sp.nov. Antonie van Leeuwenhoek 39, 4°1-4°8. MATSUSHIMA, K. (1971). Mycological reports from New Guinea and the Solomon Islands 7. Some interesting Fungi Imperfecti. Bulletin of the Natural Science Museum, Tokyo 14, 460-480. MATSUSHIMA, K. (1975). leones microfungorum a Matsushima lectorum. Matsushima, Kobe. NAWAWI, A. (1973). A new species of Flabellospora from Malaysia. Malaysian Journal of Science 2, 55-58. NAWAWI, A. (1976). Another new Flabellospora. Transactions of the British Mycological Society 66, 543547· NEWHALL,A. G. (1946). More on thenameofAnsatospora acerina. Phytopathology 36, 893-896. NILSSON, S. (1962). Some aquatic hyphomycetes from South America. Svensk botanisk Tidskrift 56, 351-361. OLIVE, L. S., LEFEBVRE, C. L. & SHERWIN, H. S. (1946). The fungus that causes sooty stripe of Sorghum spp. Phytopathology 36, 190-200. PETCH, T. (1921). Studies in entomogenous fungi. I. The Nectriae parasitic on scale insects. Transactions of the British Mycological Society 7, 89-167. PETERSEN, R. H. (1962). Spore formation in Tricellula v.

E. Descals and Bev. and Volucrispora Haskins. Bulletin of the Torrey botanical Club 89, 287-293. PETERSEN, R. H. (1963). Aquatic hyphomycetes from North America III. Phialosporae and miscellaneous species. Mycologia 55, 570-581. PIROZYNSKI, K. A. & SHOEMAKER, R. A. (1972). Vestigium felicis, a new genus of Coelomycetes. Canadian Journal of Botany 50, 1163-1164. PREUSS, C. G. T. (1851). Uebersicht untersuchter Pilze, besonders aus der Umgegend von Hoyerswerda. Linnaea 24, 99-153. PRICE, I. P. & TALBOT, P. H. B. (1966). An aquatic hyphomycete in a lignicolous habitat. Australian Journal of Botany 14, 19-23. RABENHORST, L. (1907). Kryptogamenfiora von Deutschland, Osterreich, und der Schweiz, vol. I. Leipzig: Lummer. RANZONI, F. V. (1953). The aquatic hyphomycetes of California. Farlowia 4, 353-398.

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SACCARDO, P. A. (1876). Fungi veneti novi vel critici. Nuovo Giornale Botanico Italiano 8, 161-211. SPEGAZZINI, C. (1911). Mycetes argentinenses. Anales del Museo Nacional de Buenos Aires 3, 463-465. SPRAGUE, R. (1937). Undescribed species of Cercosporella and Cercospora on certain grasses in Oregon and Washington. Mycologia 29, 199-206. STOJANOVIC, D. J. & BORIC, B. (1974). Role of the saprophytic phase of the development cycle of Coccomyces hiemalis Higg. in the renewal of primary infections. Zastita Bilja 25, 177-183. SUBRAMANIAN, C. V. (1977). Revision of hyphomycetes. I. Kavaka 5, 98-98. WEBSTER, J. (1954). The microfungi of Dactylisglomerata. Ph.D. Thesis, Unversity of London. WILDEMAN, E. DE (1895). Notes mycologiques. Annales de la Societe beige de Microscopie 19, 193-206.

(Received for publication 10 June 1981)