Dictyosporium digitatum, a new hyphomycete from Taiwan

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Short Communications shining, smooth, membranous, dehiscing by a tom apical stoma. Subgieba well-developed, pale yellow to light brown, distinctly chambered. Glebe olive brown to brown, pulverulent. Capillitial threads yellowish brown or olive brown, dichotomously branched, aseptate, up to 11'5 IJm wide; wall dark, up to 1'7 IJm thick, pitted, pores few. Basidiospores subglobose to broadly ovoid, 4'3-5 x 3'8-4'3 IJm, pale olive brown, verruculose, verrucae minute, distinctly visible when stained in cresyl blue, covered by a hyaline myxosporium, pedicellate, pedicel thin, hyaline, straight or curved, up to 19 IJm long. Exoperidium composed of globose or subglobose inflated elements, arranged in a chain; endoperidium comprises slightly thick-walled, irregular and setiform hyphae towards the outer side. On humicolous soil rich in ligneous debris in Cryptomeria japonica forest. Material examined: India: West Bengal. Darjeeling, Dhotre (2200 m), 10 Sept. 1979, PAN 23166, holotype, LG, isotype; PAN 23225, LG, 23 Aug. 1980; nr Sukhia, PAN 23231. LG, 29 Aug. 1980; Palmjuha; BMS 23236, PAN, LG, 30 Aug. 1980.

Features such as the chambered subgleba and dehiscence by an apical stoma separate Lycoperdon from related genera such as Bovista Dill.: Pers., and Calvalia Fr. The Indian collections are therefore referred to Lycoperdon Tourn.: Pers. In Bovista, the subgleba is usually lacking but it is compact when present (Kreisel. 1967). Calvalia usually has a thin, fragile endoperidium breaking up into segments at maturity thus exposing the glebal mass. Lycoperdon darjeelingense is distinguished by a spinose or warty, darker exoperidium, well-developed subgleba and subglobose to broadly ovoid, minutely verruculose pedicellate basidiospores. It is remarkable in having irregular, setiform hyphae of the endoperidium, thus indicating a tomentose aspect. In this feature, it differs from all the species of the

genus with pedicellate basidiospores. Despite this difference, the commonly used morphological features show that L. pedicellatum Peck is a close relative of L. darjeelingense. However, it has rather long, whitish spines of the exoperidium and basidisopores with long pedicels up to 30 (-40 IJm). Pedicellate basidiospores might suggest a relationship with other species such as L. rimulatum Peck ex. Trelease and L. mundkurii Ahmad, but the former has a rimose-areolate exoperidium, purplish brown gleba and globose strongly verrucose basidiospores, and the latter can easily be distinguished by its broad ellipsoid, smooth basidiospores (Ahmad, 1942). L. yasudae (Lloyd) Kreisel (1969) is another species related to L. darjeelingense but can be separated by its strongly spinose (spines up to 2 mm long) exoperidium (spines on falling leave distinct scars which give a pitted appearance to the surface) and globose verruculose basidiospores 5'0-5'7 IJm. The author wishes to thank the Department of Science and Technology, Government of India, for financial assistance under the project, 'Mycoflora of the Eastern Himalayas'; to Professor K. S. Trund for help and guidance; to Dr V. Demoulin, Department of Botany, University of Liege, Belgium for ascertaining the identity of the species.

REFERENCES Ahmad, S. (1942). Gasteromycetes of N. W. Himalayas. II. Journal of the Indian Bolanical Society 21. 283-293. Holmgren, P. K. & Keuken. W. (1974). Index Herbariorum 16th edn. Regnum Vegelabile 92, 1-397. Kreisel. H. (1967). Taxonomische-pflanzengeographische Monographie der GaHung Bovisla. Beih., Nova Hedwigia 25, 1-244. Kreisel. H. (1969). Gasteromyceten aus Nepal. Khumbu Himal 6. 25-35. Sharma, B. M. (1982). Studies on the Gasteromycetes of Eastern Himalayas and adjoining hills. Ph.D. Thesis, Panjab University, Chandigarh. India.

(Received for publication 20 November 1990)

Dictyosporium digitatum, a new hyphomycete from Taiwan J. 1. CHEN, C. H. HWANG AND S. S. TZEAN Department of Plant Pathology and Entomology, National Taiwan University, Taipei, Taiwan 10764,

R.o.c.

Dictyosporium digitalum sp. nov. is described from a fallen. decaying herbaceous stem. It is sporodochial and characterized by cheiroid conidia consisting of 4-8 parallel. tightly appressed arms which are flattened in one plane. Arms ascend from a more or less triangular basal cell. The apex of each arm is digitate, distinctly thin-walled, hyaline. straight or flexuous, incurved or even curled. The morphological distinction between D. digitatum and other closely related species in Dietyosporium, Cheiromyces and Cheiromyce/la is discussed.

Dictyosporium was erected by Corda (1836) to accommodate deuteromycete genera with cheiroid or digitate brown conidia; a Single species, D. elegans, which is characterized by cheiroid twenty species were accepted and other doubtful species were conidia (Ellis, 1971). Damon (1952) studied and compared the , excluded. Recently D. gaunlii Bhat & Sutton (1985), D. types in Dictyosporium, Speira and CaUanea, and proVided a verrucosum Tzean & Chen, D. bulbosum Tzean & Chen (1989) key to Dictyosporium, including seven accepted species. Sutton were described and this brought the total number in (1985) published a note with brief discussion on some Dictyosporium to 23 (Batista et al., 1960; Batista & Farr, 1960;

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Ellis, 1971; Gareth Jones, 1963; Kirk & Spooner, 1983; Saccardo, 1918; Matsushima, 1975, 1980, 1981; Subramanian, 1971; Tzean & Chen, 1989; Van Emden, 1975). D. gauntii is distinctive because of the huge, terminal, integrated, oval to ellipsoid conidiogenous cells, D. verrucosum by the verrucose conidia consisting of (2)3 short arms, and D. bulbosum by the apical cell of the outer row of the conidia being ornamented with hyaline, thin-walled ovoid to bulbous appendages (Bhat & Sutton, 1985; Tzean & Chen, 1989). Recently, in surveying Hyphomycetes from Taiwan, an additional unique Dictyosporium was obtained from a fallen decaying herbaceous stem. This strain has cheiroid conidia consisting of arms ornamented with digitate, distinctly thinwalled, hyaline, apical cells, which differed from any previously described Dictyosporium species. The description and diagnosis are based on culture on com meal agar (CMA) and on the natural substratum. Kornerup & Wanscher (1978) is used as the colour standard.

Dictyosporium digitatum Chen, Hwang & Tzean, sp. nov. (Figs 1-4) Coloniae diametro in CMA 48-51 mm in 21 diebus, effusae, sporodochiis abundantibus, flavido-brunneae vel atro-brunneae, dispersae in centralibus areis, vel zonatae, 1-3 circulis in submarginibus, usque ad 400 ~m latae. Mycelium fere immersum, partim superficiale, album, griseo-album, ravido-flavum, constitutum ramosis, septatis, laevibus, scabris vel verrucosis, hyalinis vel brunneis hyphis, (0'8) 1'5-4'0 (4'8) ~m latum; solubile pigmentum pallidum flavum vel leviter luteum; reversum incolor, aurantiacum luteum vel flavidobrunneum. Conidiophora micronematosa, simplicia vel irregulariter ramosa, recta vel flexuosa, laevia, aspera vel verrucosa, hyalina vel brunnea. Cellulae conidiogenae in conidiophoris incorporatae, vel discretae, hyalinae vel brunneae, cylindricae, doliiformes, cuneiformes,

subglobosae, globosae, laeves, 3'2-8'7 x 2'8-8'0 ~m. Conidia solitaria, holoblastica, cheiroidea, pallide rubro- vel atrobrunnea, glabra, 54-114 x 18-42 ~m, cum plus minusve triangulibus basilaribus cellulis in quibus (4)6-8 parallelis, arcte appressa brachia orientia, complanata in uno plano, omnia brachia cum usque ad 24 septa, septa plerumque constricta, cellula terminalis distincte leptoderma, hyalina, digitata, recta vel flexuosa, incurva vel etiam cincinnata, toti numeri conidicorum cellularum (57)79-184. In avenis farinis agaris (OMA) sporodochia usque ad 1000 ~m lata. Holotypus in caulis dejectis, Wulai, Taipei, Taiwan, R.O.C. 16 Jan. 1990, PPH 12, isotypus IMI.344647.

Colonies on natural substratum consisting of effuse, septate, branched greyish blue to dark blue mycelium and abundant sporodochia. Sporodochia scattered or confluent, superficial or immersed in crevices, globose, subglobose, ellipsoidal, fusiform or irregularly-shaped. Conidiophores micronematous, simple or branched, smooth, hyaline to brown, often constricted at the septa. Conidiogenous cells integrated, subglobose, doliiform, cuneiform, thin-walled, smooth, hyaline or brown, 4'210'0 I-lm long, 3'3-7'5 I-lm wide. Conidia solitary, dry, holoblastic, cheiroid, greyish orange to reddish golden or reddish brown, smooth-walled, 46'7-74'2(77'5) I-lm long, 22'5-36'7(39'2) I-lm wide, with a more or less triangular basal cell, 4'2-6'3 I-lm wide, on which 5-7 parallel, tightly appressed arms arise flattened in one plane, each arm with (4)7-13(14) septa, septa usually constricted, cells 3'0--8'8 I-lm wide, terminal cell distinctly thin-walled, hyaline, digitate, straight or flexuous, incurved or even curled, total number of conidial cells (54)57-88(94). Colonies, diameter on CMA 48-51 mm in 21 d, effuse, sporodochia abundant, yellowish brown to dark brown, scattered in central area, or zonate, 1-3 circles in submargin, up to 400 I-lm wide, Mycelium mostly submerged, partly

Fig. 1. Dietyosporium digitafum. Sporodochia dark brown formed on natural substratum, punctiform, ellipsoid, or irregular-shaped (arrows). Bar = 2 mm.

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Fig. 2. Dictyosporium digitatum. Cheiroid conidia formed on natural substratum with digitate thin-walled, straight, flexuous or incurved apical cells. superficial, white, grey-white, greyish yellow, composed of branched, septate, smooth, roughened or verrucose, hyaline to brown hyphae, (0'8)1'5-4'0(4'8) I..lm wide; soluble pigment pale yellow to lightly yellow; reverse colourless, orange yellow to yellowish brown. Conidiophores micronematous, simple, or irregularly branched, straight or flexuous, smooth, roughened or verrucose, hyaline or brown. Conidiogenous cells integrated or discrete, hyaline to brown, cylindrical, doliiform, cuneiform, subglobose, globose, smooth, 3'2-8'7 x 2'88'0 I..lm. Conidia solitary, holoblastic, cheiroid, light reddish or dark brown, smooth, 54-114 x 18-42 I..lm, with a more or less triangular basal cell on which (4)6-8 parallel, tightly appressed arms arise, flattened in one plane, each arm with up to 24 septa, septa usually constricted, terminal cell distinctly thinwalled, hyaline, digitate, straight, or flexuous, incurved or even curled, total number of conidial cells (57)79-184. On oat meal agar (OMA) sporodochia up to 1000 I..lm wide. Specimens examined: on fallen, decaying herbaceous stem, Wulai, Taipei, Taiwan, R.O.C. 16 Jan. 1990, h010type PPH 12 (dried culture) and ex-type PPH 12E (living culture), deposited in the Department of Plant Pathology and Entomology, National Taiwan University, Taipei, Taiwan, R.o.C. PPH 12E was also deposited in Culture Collection and Research Center (CCRC32530), Hsinchu, Taiwan, isotypes in herb. NY, New York Botanical Garden, U.S.A., herb. 1M] 344647, UK

The most noticeable morphological characteristic of Dietyosporium digitatum is the digitate, thin-walled, hyaline, straight or flexuous, incurved, or curled apical cells in each arm of the conidia. Such digitate ornamentation actually could be seen by light microscopy of the conidia either from the natural

Fig. 3. Dictyosporium digitatum. Cheiroid conidia from CMA culture plate; the gross morphological characteristics are generally similar to that on natural substratum but longer and wider.

substratum or culture plates without mounting or other treatment. This ornamentation is not an artifact. The digitate appendages of D. digitatum distinguish it from D. bulbosum and D. alatum Van Emden, the latter two species having bulbous or allantoid, hyaline thin-walled appendages arising from the apical cell of the outer row of the conidia, respectively (Tzean & Chen, 1989; Van Emden, 1975). The cheiroid conidia of D. digitatum were flattened in one plane and they differ from D. heptosporum (Garovaglio) Damon, in which the arms comprising the conidia are inserted in different planes, though both species showed some similarity in conidial morphology and size, also in the formation of sporodochia. In addition mature conidia of D. heptosporum in water preparations formed fragile, bulbose, hyaline apical ornamentations, but they are absent from dry mounts and thus interpreted as an artifact (Rao & De Hoog, 1986). Recently, Sutton (1985) redefined the genus Cheiromyces Berk. & M. A. Curt. and only accepted the type species, C. stellatus Berk. & M. A. Curt., which was characterized by forming sporodochia, short cylindrical conidiophores bearing branched arms, and distoseptate conidia (Sutton, 1985). The arms originated from a single basal cell, and formed in three planes (Damon, 1950). Among the several described species (Matsushima, 1987; Rao & De Hoog, 1986; Arambarri et al.,

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Fig. 4. Dicfyosporium digitatum. Cheiroid conidia from CMA culture plate. Note the varied-shaped conidiogenous cells and a more or less triangular basal cell (arrows). Bar = 10 11m.

1987), C. inflatus Matsushima is the only species having cheiroid conidia with apically inflated bulbose cells, 8-12 Ilm diam. Despite C. inflatus showing a superficial similarity in conidiogenous cells, conidial basal cells, and appendage ontogeny to D. digitatum, both species can be easily separated by gross conidial morphological characteristics. Some of the generic circumscriptions for Dictyosporium and Cheiromyces

overlap. Thus, in some instances, species which have sporodochia, cheiroid conidia and branched arms inserted in more than one plane are common to genera and are quite difficult to separate, and therefore need further study. Cheiromycella moniliphora Matsushima was also characterized by cheiroid conidia having arms with inflated bulbous apical cells, however, conidiophores are macronematous, conidio-

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Short Communications genous cells branched, catenulate, monilioid, and markedly different from D.

digitatum (Damon, 1952; Ellis, 1971; Sutton,

1985; Matsushima, 1987).

This work was supported by National Science Council.

R.O.c.. grant NSC-79-0409-B002-35. The authors are indebted to Dr B. C. Sutton for critical review and invaluable assistance in preparation of the manuscript; to Dr J.

c. Liao for

preparation of the Latin diagnosis.

REFERENCES Arambarri, A, Cabello, M. & Mengascini, A (1987). New Hyphomycetes from Santiago River. II. (Buenos Aires Province, Argentina). Mycotaxon 30, 263-267. Batista, A Bezerra, j. L.. De Siqueira, M. W. & Peres, G. E. P. (1960). Benekea n. gen. e outros fungos imperfeitos. Publica,ao Instituto Micologia Recife 299, 24-25. Batista, A C. & Farr, M. L. (1960). Algumas especies de Dictyosporium e Podosporium. 1. Saccardoa 1, 103-104. Bhat, D. j. & Sutton, B. C. (1985). New and interesting Hyphomycetes from Ethiopia. Transactions of the British Mycological Society 85, 107-122. Damon, S. C. (1950). A taxonomic consideration of two cheirosporous genera, Cheiromyces and Pedilospora. Mycologia 42, 554-562. Damon, S. C. (1952). Type studies in Dictyosporium, Speira, and CaUanea. Lloydia 15, 110-124.

c..

Ellis, M. B. (1971). Demaliaceous Hyphomyceles. International Mycological Institute: Kew, England. Gareth jones, E. B. (1963). Marine fungi. II. Ascomycetes and Deuteromycetes from submerged wood and drift spartina. Transactions of the British Mycological Society 46, 135-144. Kirk, P. M. & Spooner, B. M. (1983). An account of the fungi of Arran, Gigha and Kintyre. Kew Bulletin 38, 503-597. Kornerup, A 8< Wanscher, L H. (1978). Melhuen Handbook of Colour. London: Eyre Methuen. Matsushima, T. (1975). Icones Microfungorum a Matsushima Lectorum. Matsushima: Kobe, japan. Matsushima, T. (1980). Saprophytic microfungi from Taiwan. Part I. Hyphomycetes. Matsushima Mycological Memoirs 1, 1-82. Matsushima: Kobe, japan. Matsushima, T. (1981). Matsushima Mycological Memoirs 2, 1--68. Matsushima: Kobe, japan. Matsushima, T. (1987). Matsushima Mycological Memoirs 5, 1-100. Matsushima: Kobe, japan. Saccardo, P. A (1918). Notae Mycologicae. I. Fungi Singaporensis Bakgiana. II. Fungi Abellinensis Novi. BolleUino de/fOrto botanico Napoli 6, 72. Subramanian, C. V. (1971). Hyphomycetes. Indian Council of Agricultural Research: New Delhi, India. Sutton, B. C. (1985). Notes on some deuteromycete genera with cheiroid or digitate brown conidia. Proceedings of the Indian Academy of Sciences (Plant Science) 94, 229-244. Tzean, S. S. & Chen, j. L. (1989). Two new species of Dictyosporium from Taiwan. Mycological Research 92, 497-502. Van Emden, j. H. (1975). Three new fungi from Surinam soil. Acta Botanica Neerlandica 24, 193-197. Vasant Rao & De Hoog, G. S. (1986). New or critical Hyphomycetes from India. Studies in Mycology 28, 1-84.

(Received for publication 21 December 1990)

Phomopsis mangrovei, from intertidal prop roots of R/tizophora spp. KEVIN D. HYDE Plant Pathology Branch, Queensland Department of Primary Industries, Mareeba, Qld 4880, Australia Phomopsis mangrovei sp. nov. is described from dead prop roots of Rhizophora apiculata in Thailand.

Numerous decayed prop roots of Rhizophora apiculata collected at Ranong Mangrove in Thailand were colonized by a Phomopsis sp. which is described as new. In some areas almost half of the attached prop roots were dead. These trees were young and uncrowded and whilst prop roots may die naturally or due to storm damage, there was no obvious cause of damage. It is thought that the fungus may be pathogenic,

Conidia holoblastica, (ex) 11-18 x 3-4 \lm, hyalina, fusiforrnia vel ellipsoidea, 0-3 gu~~ula~a, asepta~a.

Holotypus : Thailand, Ranong mangrove, in~ertidal young prop roo~s of R. apiculata, Nov. 1988, K. D. Hyde, IMI 332466.

Conidiomata ellipsoid or subglobose, 250-400!-lm long, 130-195 !-lm wide and 162-260!-lm high, eustromatic, im-

although no tests were carried out to confirm this suggestion.

mersed, black, separate or aggregated in groups of 2-3,

TAXONOMY Phomopsis mangrovei Hyde, sp. nov.

upper region and lined with a layer of highly melanized

unilocular, thick-walled, of textura angularis, darker in the (Figs 1-7)

Conidiomata ellipsoidea vel subglobosa, 250-400 \lm longa, 130195 \lm lata et 162-260 \lm alta, eustromatica, immersa, nigra, separata vel aggregata, W1ilocularia, ostiolata, pachydermia, texturam angularem forrnantia. Conidiophora ad per 52 IJm longa, ramosa, valida vel filiforrnia, sep~ata, hyalina. Cel/ulae conidiogenae phialidicae, deterrninatae, in conidiophoris incorpora~ae, hyalinae, cylindricae.

smaller celled tissue.

Conidiophores up to 52

Ostiole Single, circular, non-papillate. I-lITI long, branched, stout or filiform,

septate at the base with 0-3 septa above, hyaline, formed from the inner cells of the locular walls.

Conidiogenous cells

phialidic (sensu Sutton, 1980), determinate, integrated, hyaline, cylindrical, collarette, channel and periclinal thickening minute. Conidia holoblastic, of one type only (ex), 11-18 x 3-4 !-lm,