Spororminula tenerifae gen. et sp.nov.

Notes and brief articles bisporic basidia, subamygdaliform spores, and lacking both cystidia and clamp-connexions. It is therefore placed in the genus Pleu romycenula, with similarities in the minute, white, stipitate basidiocarps growing in moss, with a smooth hymenophore and the strongly inflated context hyphae. Till now three species are recognized as belonging to this genus (Singer, 1986). This species differs from them in having a central st ipe and in lacking both cystidia and clamp-connexions. Hence it is described here as a new species.

117

We are indebted to Dr D . N. Pegler for a critical reading of the manuscript. On of us (P. M .) acknowledges the financial assistance from CSIR, New Delhi. REFERENCE

R . (1986). The Agaricales in Modern Taxonomy, 4th edn . Koenigstein: Koeltz Scientific Books.

SINGER,

SPORORMINULA TENERIFAE GEN . ET SP .NOV . BY

J. A.

VON ARX AND H . A. VAN DER AA

Centraalbureau voor Schimmelcultures, Baarn, The Netherlands Spororminula gen.nov. differs from other Sporormiaceae (Dothideales) by ostiolate ascomata and transversely septate ascospores with cells triangular in transverse section and without germ slits. A key to the genera accepted in the Sporormiaceae is provided. Spororminula tenerifae sp .nov . has been isolated from droppings collected on Tenerife at an altitude of 2300m.

During a stay on Tenerife (Canary Islands) in March 1986, the first author collected plant debris, soil samples and droppings in Las Canadas at an altitude of about 2300 m. Only a few endemic shrubs grow in this extremely arid area; Spartacytisus supranubius (L.) Webb & Berth., Adenocarpus viscosus (Willd.) Webb & Berth., Descurainia bourgeana Webb and Pterocephalus lasiospermus Link are the most common. Incubated in Petri dishes on wet filter paper, several fungi developed on the droppings (apparently of rabbits), among which were Neosartorya fis cheri (Wehm er) Malloch & Cain , Sordaria aff. goudaensis Cailleux, Chaetomium crispatum Fuckel, Chaetomium cuniculorum Fuckel, Gymnoascus reessii Baranetzki, Phaeotrichum circinatum Cain (very abundant), Preussia australis (Speg.) v. Arx, Circinomucor plumbeus (Bonorden) v. Arx, Circinomucor sphaerosporus (Hagem) v. Arx, Cephalotrichum stemonitis (Pers.) Link, Monodictys sp. (apparently undescribed) and several other hyphomycetes. A member of the Sporormiaceae developed on a few droppings and it could not be identified with any species treated by Cain (1961), Ahmed & Cain (1972), von Arx & Storm (1967) and others. The fungus differs from all species of Preussia and Sporormiella in its ascospores, which are composed of cells without germ slits and which are triangular in transverse section. Sporormia sensu Ahmed & Cain (1972) is characterized by ascospores composed of more than 15 cells without germ slits, which are united by a common gelatinous sheath. Trans. Br. mycol. Soc. 89 (1), (1987)

The ascospores of the present fungus are relatively large compared with Sporormia , eight-celled and the cells separate easily from each other. It therefore may be classified in a separate genus. Spororminula von Arx & van der Aa, gen.nov. Fimicola; ascomata ovata vel ampulliformia, nigra, ostiolata; asci cylindrici, bitunicati, octospori; ascosporae cylindricae, pluriseptatae, sine fissura germinationis, strato mucoso circumdatae ; paraphyses praesentes. Species typica : Sp ororminula tenerifae

Spororminula tenerifae von Arx & van der Aa, sp .nov. (Fig. 1) Fimicola; ascornata immersa vel erumpentia, ovata vel ampulliformia, distinete osti olata , nigra, mernbranacea, 260-400 pm diam ; asci cylindrici, clavati vel saccat i, stipitati, bitunicati, octospori, 150-220 x 30-40 p m; paraphyses numerosis, filamentosis, hyalinis; ascosporae cylindracae, triangularia in sectio transverso, 7-septatae, constrictae ad septis, brunneae, sine fissura germinationis, stato mucosa angusto hyalino obductis, 72-108 x 14- 19 pm.

T ypus ex fimo ignoto Las Canadas, Tenerife, Canary IsJ., Mar. 1986, J. A. von Arx , CBS H 4032, e cultura CBS 354.86 .

Ascomata immersed when young, becoming erumpent, ovate -ampulliform, with a spherical cavity, 260-400 Ilm diam, and with a cylindrical or conical ostiolar beak, 200-250/lm broad and 120-160/lm high, smooth or covered with some pigmented hyphae; ascomatal wall relatively thin, membranaceous, composed of several layers of irregular, elongate or angular, 2'5-5 /lm broad cells

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Notes and brief articles

118

".

I

I Fig.

1.

Spororminula tenerifae, ascomata in vertical section (bar, 100.um), asci, ascospores, ascospore cells and hyphal swellings (bars, 20 11m).

Trans. Br. mycol. Soc. 89 (1), (1987)

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Notes and brief articles (indistinct textura epidermoidea in surface view); asci cylindrical-clavate or saccate, distinctly stalked, bitunicate, inner wall with an apical bulge, apically broadly rounded, 8-spored, 150-220 x 30-40 ,urn; paraphyses numerous, filamentous, hyaline, aseptate, evanescent; ascospores cylindrical-clavate, with 7 transverse septa and a gelatinous sheath, rather thick-walled and brown when mature, 72-108 x 14-19,um (without sheath), easily separating into single cells; central cells of the ascospores shorter than broad, rectangular in vertical section, triangular in transverse section, 15-18 x 12-15 ,urn, without visible germ slits or pores, apical cells usually longer than broad, 15-18,um long, also without apertures. Pure cultures were achieved from germinating ascospores. The colonies on cornmeal or oatmeal agar grow slowly and attain a diameter of 18-20 mm in 10 days under near U.V. at 24°C. The reverse is brown and nearly opaque. The aerial

mycelium is relatively sparse, lanose, greyish or brownish and is composed of thin-walled, septate, scarcely branched, pale brown, 2-3' 5 ,urn diam hyphae. The submerged mycelium is intermixed with darker hyphae up to 5 ,urn diam. Subglobose hyphal swellings are present in 4- to 6-week-old cultures. The swollen cells have a diameter of up to 10 ,urnand are covered by a dark brown, crustose mass; they often are arranged in long chains. Mature ascomata were observed in 4- to y-week-old cultures. Their structure is similar to those of the ascomata on the natural substrate. Cultures of Spororminula tenerifae were incorporated in the CBS culture collection, CBS 354'86 and permanent slides, dried droppings and dried cultures preserved as CBS H 4032. The Sporormiaceae now includes the genera Sporormia, Spororminula, Preussia, Sporormiella, Westerdykella and Pycnidiophora, which can be distinguished with the following key.

KEY TO GENERA OF SPORORMIACEAE

1. Ascospore cells with obvious germ slits . 2 1. Ascospore cells without germ slits . 3 2. Ascomata spherical or turbinate, ostiolate or non-ostiolate ; on plant debris, wood or isolated from soil Preussia 2. Ascomata ampulliform, with a distinct ostiolar beak; exclusively coprophilous . Sporormiella 3· Ascospores long-cylindrical, fasciculate, composed of more than 15 cells, united by a common sheath Sporormia 3· Ascospores 3- to 7-septate, easily separating into single cells. 4 4. Ascomata ostiolate ; ascospores large, 7-septate . . Spororminula 4. Ascomata non-ostiolate, spherical; ascospores small, 3-septate when young, cells separating within the asci in an immature state . 5 5. Ascospore cells smooth, rod-shaped Pycnidiophora 5. Ascospore cells swollen, with spiral-like ridges Westerdykella

Pycnidiophora has been placed in synonymy with Preussia by Cain (1961) and with Westerdykella by Cejp & Milko (1964), which was accepted by some subsequent authors. Preussiella Lodha (in Subramanian, 1978) is an obligate synonym of Pycnidiophora. Sporormiella was reintroduced by Ahmed & Cain (t 972); they classified in it about 60 coprophilous species with ostiolate ascomata and ascospores with germ slits. Non-coprophilous relatives were neglected. Von Arx (1973) put Sporormiella in synonymy with Preussia. In several species he observed ostiolate and non-ostiolate strains, e.g. in Preussia minima (Auersw.) v. Arx, P. fleischhakii (Auersw.) Cain and P. aemulans (Rehm) v. Arx. This last species is closely related to Preussia leporina (Niessl) v. Arx (Sporormiella leporina (Niessl) Ahmed & Cain), but can easily be distinguished by the structure of the ascospores and by the usually non-ostiolate, sphericalturbinate ascomata, P. aemulans occurs on plant Trans. Br. my col. Soc. 89 (1), (1987)

debris, wood and is soil borne; P. leporina is very common on rabbit dung. Only a few of the species classified by Ahmed & Cain (1972) in Sporormiella have been transferred to Preussia. Probably the name Sporormiella can be maintained for the coprophilous relatives of Preussia with ampulliform, distinctly ostiolate ascomata, as indicated in the key given above. The authors thank Dr P. F. Cannon for reading the manuscript and for useful suggestions. REFERENCES

AHMED, S. 1. & CAIN, R. F. (1972). Revision of the genera Sporormia and Sporormiella. Canadian Journal of Borany S0, 41({"-477. ARX, J. A. von (1973). Ostiolate and nonostiolate Pyrenomycctes. Proceedings Koninklijke Nederlandse Akademie van Wetenschappen, Series C, 76, 28({"-296. ARX, J. A. von & STORM, P. K. (1967). Ueber einige aus dem Erdboden isolierte, zu Sporormia, Preussia und

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120

Westerdykella gehorende Ascomyceten. Persoonia 45, 407-4 15. CAIN, R. F. (1961). Studies of coprophilous Ascomycetes VII. Preussia. Canadian Journal of Botany 39, 1633-1666.

CEJP, K. & MILKO, A. A. (1964). Genera of Eurotiaceae with 32 ascospores. I. Westerdykella. Ceska Mykologie 18,82-84. SUBRAMANIAN, C. V. (ed.) (1978). Taxonomy of Fungi 1, 241-257. Madras: University of Madras.

NOTES ON MYCOSPHAERELLA FIJIENSIS VAR. DIFFORMIS BY NINOSKA PONS

Centro Nacional de Investigaciones Agropecuarias, Ceniap, Apdo 4653, Maracay

2101,

Venezuela

On the basis of microscopical examination of the type collections of Paracercospora fijiensis (anamorph of Mycosphaerellafijiensis) and P. fijiensis var. difformis (anamorph of M. fijiensis var. dijJormis) these names are considered to be synonymous. The black leaf streak caused by Mycosphaerella fijiensis Morelet and black Sigatoka caused by M. fijiensis var. dijJormis Mulder & Stover, have been referred to as two of the more severe diseases affecting banana and plantain (Musa spp.) crops in Tropical America (Meredith & Lawrence, 1969; Meredith, 1970; Mulder & Stover, 1976; Anon., 1980). Because of the resemblance of symptoms, the diagnosis of these two diseases is based on microscopical examination of affected tissue. However, the morphological differences between the two fungi involved are not clear cut. This situation makes the separation of M. fijiensis var. fijiensis from M. fijiensis var. dijJormis confusing. The name M. fijiensis var. dijJormis assigned to the fungus which causes black Sigatoka was first mentioned in Honduras by Stover (1974). Neither a Latin diagnosis nor type material were given. The name was later validated on the basis of examination of Musa sp. collections from La Lima, Honduras by Mulder & Stover (1976). The taxonomic criterion used to separate the variety 'dijJormis' was the presence of a sporadic stroma as the origin for dense or loose fascicles of conidiophores, in contrast with the absence of a stroma for the anamorph of M. fijiensis (Mulder & Stover, 1976). The anamorphs of M. fijiensis var. fijiensis and M. fijiensis var. dijJormis, previously referred to Cercospora Fres. (Morelet, 1969; Mulder & Stover, 1976), were later transferred to the new genus Paracercospora Deighton under the combinations Paracercospora fijiensis (Morelet) Deighton and P. fijiensis var, dijJormis (Mulder & Stover) Deighton. The conidiogenous locus of these reassigned fungi showed the thickening confined to a narrow rim around the scar, a characteristic of the genus Paracercospora (Deighton, 1979). Although Deighton mentioned the sporadic presence of a stroma in P. fijiensis var. difformis in comparison with the absence of this structure Trans. Br. mycol. Soc. 89 (1), (1987)

in P. fijiensis var. fijiensis, he did not make any observation about the value of such criteria for separating the two varieties. But Hawksworth (1974) had pointed out that the rank of variety was commonly used in mycology to distinguish populations which consistently differ by a character with no merit for separate species. The mere fact that the presence of the stroma in P. fijiensis var. dijJormis is known to be an inconsistent feature, suggests that the new variety was not well founded. In addition, the present study of the holotype collections of M.fijiensis var.fijiensis (IMI 136696) and M.fijiensis var. dijJormis (IMI 183747) showed development of conidiophores on a simple stroma or on a stroma from young spermogonia on both collections (Figs 1, 2). The occurrence of fascicles of conidiophores without a stromatic basis was not observed, probably because of the meagre condition of the type materials. This aspect, however, was confirmed on specimen VIA 4935 of M. fijiensis var. dijJormis from Uraba, Colombia. In any case, this feature, described as common to both varieties does not conflict with the similarities here established. The following synonymy is therefore proposed: (Morelet) Deighton, Mycol. Pap. 144: 51 (1979). (Fig. 1) Paracercospora fijiensis var. dijJormis (Mulder & Stover) Deighton, Mycol. Pap. 144: 52 (1979). (Fig. 2) Anamorph of Mycosphaerella fijiensis Morelet Caespituli amphigenous, predominantly hypophyllous, dark brown, scattered on the lesion. Stroma none or moderately developed, textura angularis, substornatal, erumpent, or on young spermogonia, brown. Conidiophores in loose or dense fascicles, continuous or septate, smooth, cylindric, simple, olivaceous brown, regeneration enteroblastic, up to 25 p,m long, 3-4 p,m wide at the base and at the PARACERCOSPORA FIJIENSIS

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