A new variety of coprophilous Schizothecium from France

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1 A new variety of coprophilous Schizothecium from France DOVERI F.* & COUÉ B.** * via Baciocchi 9, Livorno-Italy. E.mail: f.doveri@sysnet.it ** 24 rue des Fours, Coudré, F Clussais la Pommeraie, France. E.mail: bruno.coue@wanadoo.fr ABSTRACT The authors, after a briefly commenting on the benefits of Italo-French cooperation for the study of coprophilous fungi, describe Schizothecium curvuloides var. megasporum var. nov. They discuss the main features of the schizothecioid species of Podospora, and explain why they now consider those species to belong in Schizothecium, a genus they now accept to be distinct from Podospora. Podospora vratislaviensis is recombined in Schizothecium as S. vratislaviense comb. nov. Key words: coprophilous fungi, Podospora, Schizothecium curvuloides, new combination. INTRODUCTION For many years the senior author has been interested in the study of coprophilous fungi, particularly in Italy, where he has identified and classified more than three hundred taxa (Doveri, 2004). Some of them were seen to be linked to particular faecal substrata and grow in exclusive ecological niches, so strongly restricting their distribution. Others, on the contrary, are more tolerant, for example in their nutritional and ecological requirements, and in the ease with which they can spread and become established in new localities, through cattle freight for example, even across national boundaries. Recently involved French and Italian mycologists have cooperated in studying common species and exchanging information, greatly aided by the internet. The first encouraging results of the Italo-French cooperation has resulted in a plan to census the coprophilous mycobiota in Northern France (Courtecuisse, pers. comm.). From this area we have studied numerous species never recorded from France, some of which even new for the science (unpublished observations). For some years the junior author has devoted himself to studying coprophilous fungi, with interesting results, such as findings of rare coprophilous species from West-central France (Coué et al., 2003; 2005). Cooperation with the senior author has enabled him to notice several other coprophiles from the same area (Doveri & Coué, 2005), particularly a Schizothecium very close to S. curvuloides but with some distinguishing features. This taxon is, therefore, considered to be a new variety and is described as Schizothecium curvuloides var. megasporum. MATERIALS AND METHODS We separately studied fresh material, either on samples in a moist chamber or on samples taken from the latter, kept moist by wet blotting paper, and mailed. We later compared and integrated our personal results. The non-sterilised moist chamber was prepared following the methods suggested by Richardson & Watling (1997) and Richardson (2001), slightly modified by Doveri (2004). The cultured material was examined with a stereomicroscope (magnification x 7-45) and the microscopic study carried out with Prior and Nikon Alphaphot-2 binocular microscopes with 10x eyepieces and 4x, 10x, 40x (phase contrast), 100x (oil immersion) lenses, using water as mounting medium, Indian ink as stain. 1

2 The size of spores from six perithecia of the two syntypes was measured, with more than fifty measurements made in asci with all the spores completing their maturity. Schizothecium curvuloides (Cain) L. Cai var. megasporum Doveri & Coué, var. nov. Etym.: from the Greek " µέγας, µεγάλη, µέγα " = " large " and " σπορά " = " seed, spore ", referring to the spores of this variety, which are larger than in var. curvuloides. A typo differt grandioribus peritheciis, ascis atque sporis. Syntypi hic designati: BC0113 and CLSM , fere quindecim solitaria specimina ex fimo cuniculi (Oryctolagus cuniculus), in Gallica terra invento atque culto, collecta. Leg. B. Coué, Perithecia x µm, quite variable in shape, ellipsoidal to pyriform, semimembranous and semitransparent, olive- to dark-brown, completely and finely hairy, with a blackish, semicoriaceous, conical to subcylindrical, sometimes curved neck, up to 350 x 250 µm, covered at the base with a collar of agglutinated or isolated swollen hairs, observable with a high magnification (usually over 40x). Peridium three-layered, pseudoparenchymatous, 125 µm thick on average: 1) endostratum of pale, thin-walled, polygonal cells, x 8-20 µm; 2) mesostratum of pale, thin-walled, polygonal to globose cells, x µm; 3) exostratum of thick-walled, pale brown, usually roundish, sometimes polygonal cells, x 8-25 µm, supporting numerous septate, wavy, pale brown, fairly thick-walled, smooth, very long hyphoid hairs, 2-3 µm diam., often with a bulbous base and gathered in fascicles, particularly abundant on the lower venter. At the neck the cells are blackish, papillate or elongated, cylindrical to claviform. Swollen hairs usually agglutinated at the neck base, although not forming differentiated, triangular scales, usually isolated at the venter, scarcer downward, x 8-12 µm, pale brown, one to three-celled, with a darker, conical or subcylindrical upper cell, 8-15 x 2-9 µm. Paraphyses jacket-like (in agreement with Bell & Mahoney, 1995), i.e. placed around the asci, ephemeral, soon reduced to shapeless material, septate, up to 40 µm diam. Asci x µm, 8-spored, cylindric-clavate, slightly pointed at the apex, without a clear apical apparatus, long-stalked, usually with spores maturing at different times but also with one to four spores not maturing at all. Spores irregularly uniseriate, sometimes becoming irregularly biseriate, spoon-shaped to amygdaliform and whitish in the early stages, yellowish to olive later, soon two-celled. Spore head (55.6-) (-70) x (26.8-) (- 42) µm, ellipsoidal to narrowly ellipsoidal (Q= ; Q= 1.96), symmetrical, slightly umbonate at the apex, often wider in the lower part and somewhat pointed above, dark brown to blackish, smooth, thick-walled, flattened at the base, with an apical or exceptionally somewhat eccentric germ pore, often containing a large de Bary bubble. Pedicel cylindric-conical, tapering towards the apex, 7-11 x µm, persistent. One gelatinous cauda is present at both poles, the upper one central, arising near the germ pore and often covering it, subcylindrical, more than 60 µm long, 4-5 µm diam. (at the base), seemingly hollow, smooth or transversely wrinkled, with a confused, hardly observable apical tip, the lower cauda enveloping the pedicel, ephemeral (only its base is observable, so the length cannot be measured). Neither cauda stains with Indian ink. EXAMINED MATERIAL: FRANCE: Coudré, Clussais la Pommeraie (79), 157 m, *MEN : 1729A, about fifteen superficial, scattered specimens, on rabbit dung in a moist chamber (up to 3-4 specimens on each pellet), B. Coué, , BC0113 and CLSM (personal herbaria of the authors). *Maille Elémentaire Nationale 2

3 RESULTS AND DISCUSSION Cain (1962) described ten new species of Podospora Ces., one of which, P. curvuloides, was obtained in a moist chamber from cattle dung, collected in Brazil, and so called for its resemblance to P. curvula (de Bary) Niessl [= P. conica (Fuckel) A. Bell & Mahoney; = Schizothecium conicum (Fuckel) N. Lundq.]. Since then P. curvuloides Cain has been found occasionally, particularly in Oceania from cattle (Bell, 1983; Lundqvist, pers. comm.), rabbit (?), hare, wombat (Bell, 2005), grey kangaroo (Richardson pers. comm.), horse, goat (Bell & Mahoney, 1995), and sheep (Lundqvist, pers. comm.) dung, in Asia (Wang, 1992; 2000) and East Africa (Krug & Khan, 1989; Lundqvist, pers. comm.) from cattle, in Central America (Mirza & Cain, 1969) from cow and burro, and in South America (Muroi et al., 1987) from sheep, donkey, cow, llama and alpaca. As far as we know, it has not been found in North America, and there are few reports from Europe, from cow and horse dung in Spain (Soláns, 1985), and from sheep and deer in Scotland, and rabbit in Spain (Richardson, pers. comm.). P. curvuloides is generally characterised by (sub)globose peridial cells, supporting swollen, sometimes articulated and agglutinated hairs, jacket-paraphyses, and an early spore septation, which makes the pedicel persistent and plasma-filled. These features, which can be called schizothecioid, are somewhat different from those of a true Podospora and are shared by about thirty species, many of which were transferred to Schizothecium Corda by Lundqvist (1972), who emended this genus, basing his conclusion on morphological studies. Schizothecium has also been regarded distinct from Podospora by Barrasa & Soláns (1989), Eriksson & Hawksworth (1998), Cai et al. (2005), and Eriksson (2005), the latter following the molecular studies of Miller & Huhndorf (2004) and Huhndorf et al. (2004), adapted to morphological criteria. A conflicting opinion was expressed by Furuya & Udagawa (1972), Krug & Khan (1989), Bell & Mahoney (1995), followed by Kirk et al. (2001), Doveri (2004), Chang & Wang (2005) who retained Schizothecium as synonym of Podospora. Encouraged, however, by these recent comparative analyses (Huhndorf et al., 2004; Cai et al., 2005; Miller & Huhndorf, 2005), we now consider Schizothecium Corda emend. N. Lundq. to be a distinct genus. Podospora curvuloides was invalidly renamed under Schizothecium by Barrasa & Soláns (1989) (not in conformity with article 33.3 of ICBN), but validly recombined as Schizothecium curvuloides by Cai (in Cai et al., 2005). S. curvuloides is similar to S. glutinans (Cain) N. Lundq., since they both have large spores, inconspicuous agglutinated hairs, abundant hyphoid hairs (Bell & Mahoney, 1995; Doveri, 2004; Bell, 2005), and a close phylogenetic relationship (Cai et al., 2005). It differs, however, in having transversely striate, narrowly rather than broadly ellipsoidal spores, with a shorter pedicel (Cain, 1934; Bell & Mahoney, 1995). The transverse spore striation, which appears as low ridges of the wall under a scanning electron microscope (SEM), was observed by Bell & Mahoney (1995) in almost all collections studied, typus included, although Cain (1962) did not mention this feature in the protologue. The dark, mature spore head of S. curvuloides is quite variable in size. As shown by Bell & Mahoney (1995), few collections have spores smaller than in the typus, e.g. one from Mexico (30-36 x µm versus x µm), whereas the New Zealand collections have mostly larger spores [(38-) (-58) x (17-) (-29) µm]. Also in Lundqvist s opinion (in litt.) S. curvuloides seems to have spores that vary much in form and size, not to mention the fine cross striation you can observe on some spores. Your discovery of a big-spored variety made me pick out six collections that have been shelved for two decades and that look like big-spored curvuloides. They are all from New Zealand and one from Australia. At least some of these have bigger spores and relatively broader too. The caudae swell and become colon-like. Spore size is about x µm. The perithecia are long-necked, but this may be typical of old ones only. It would be interesting to hear your opinion. Does this fungus look like your var. megasporum?. 3

4 The answer is that our new variety has even larger spores, whose shape, however, fully recalls that of S. curvuloides var. curvuloides, i.e. narrowly ellipsoidal and often with an enlarged lower portion, very similar to that drawn by Mirza & Cain (1969). Also the great variability of the perithecial shape and of the neck length, noticed in S. curvuloides var. megasporum, are comparable to S. curvuloides var. curvuloides (see the drawing in Cain, 1962), as well as the other morphological features of the new variety are comparable to the type variety, particularly the short pedicel and the inconspicuous swollen hairs, only exception being the larger perithecia, asci and spores in var. megasporum. In the latter we have neither noticed a transverse striation of the spore wall, which, on the contrary, is fairly clear in immature, still scarcely pigmented spores of var. curvuloides (Bell & Mahoney, 1995). After our remarks on the independence of Schizothecium from Podospora we wish to end this article by establishing a new combination: NEW COMBINATION Schizothecium vratislaviense (Alf. Schmidt) Doveri & Coué comb. nov. Sordaria vratislaviensis Alf. Schmidt, Verbreit. coproph. Pilze Schlesiens : 32, 1912 (basionym). Podospora vratislaviensis (Alf. Schmidt) Doveri, Fungi Fimicoli Italici : 917, = Sordaria fimbriata A. Bayer, Acta Soc. Sci. Nat. Moraviae 1 : 111, = Pleurage fimbriata (A. Bayer) W.M. Page, Trans. Brit. Mycol. Soc. 40 : 536, = Podospora fimbriata (A. Bayer) Cain, Can. J. Bot. 40 : 459, = Schizothecium fimbriatum (A. Bayer) Barrasa, Contr. Est. Tax. Ecol. Corol. Ascom. Copr. España : 473, = Bombardia lunata Zickler, Planta 22 : 573, ACKNOWLEDGEMENTS The authors thank Prof. Nils Lundqvist for the explanations about the nomenclature of Schizothecium curvuloides, and Andrew Miller for his bibliographical contribution. They are also particularly indebted to Mike Richardson for the critical revision and correction of the English text, and Gabriele Cacialli for critical revision of the manuscript. REFERENCES Barrasa J.M. & Soláns M.J., Introducción al estudio del género Schizothecium Corda emend. Lundq. en España. Rev. Ibér. Micol. 6: Bell A., Dung Fungi. An illustrated guide to coprophilous fungi in New Zealand. Victoria University Press: Wellington. Bell A., An illustrated guide to the coprophilous Ascomycetes of Australia. CBS Biodiversity Series No. 3. Centraalbureau voor Schimmelcultures. Utrecht. Bell A. & Mahoney D.P., Coprophilous fungi in New Zealand. I. Podospora species with swollen agglutinated perithecial hairs. Mycologia 87: Cai L., Jeewon R. & Hyde K.D., Phylogenetic evaluation and taxonomic revision of Schizothecium based on ribosomal DNA and protein coding genes. Fungal Diversity 19: Cain R.F., Studies of coprophilous Sphaeriales in Ontario. Univ. Toronto Stud. Mycol. Ser. 38: Cain R.F., Studies of coprophilous Ascomycetes. VIII. New species of Podospora. Can. J. Bot. 40: Chang J.-H. & Wang Y.-Z., A new species of Podospora from Taiwan. Bot. Bull. Acad. Sin. 46: Coué B., Fourré G., Hairaud M. & Lechat C., Récoltes remarquables (2002 à 2003). Bull. Soc. Mycol. Massif Argenson 21: Coué B., Fourré G., Hairaud M. & Tanchaud P., Récoltes remarquables (2004 à 2005). Bull. Soc. Mycol. Massif Argenson 23:

5 Doveri F., Fungi Fimicoli Italici. A.M.B.-Fondazione Centro Studi Micologici. Trento (pp ). Doveri F. & Coué B., First record of Pyxidiophora badiorostris from France. Doc. Mycol... Eriksson O.E., Outline of Ascomycota Myconet 11: Eriksson O.E. & Hawksworth D.L., Outline of the Ascomycetes Systema Ascomycetum 16: Furuya K. & Udagawa S., Coprophilous Pyrenomycetes from Japan I. J. Gen. Applied Microb. 18: Huhndorf S.M., Miller A.N. & Fernández F.A Molecular systematics of the Sordariales: the order and the family Lasiosphaeriaceae redefined. - Mycologia 96: Kirk P.M., Cannon P.F., David J.C. & Stalpers J.A., Ainsworth & Bisby s Dictionary of the Fungi. Ninth Edition. CAB International. Krug J.C. & Khan R.S., New records and new species of Podospora from East Africa. Can. J. Bot. 67: Lundqvist N., Nordic Sordariaceae s. lat. Symb. Bot. Upsal. 20 (1): Miller A.N. & Huhndorf S.M A natural classification of Lasiosphaeria based on nuclear LSU rdna sequences. Mycol. Res. 108: Miller A.N. & Huhndorf S.M Multi-gene phylogenies indicate ascomal wall morphology is a better predictor of phylogenetic relationships than ascospore morphology in the Sordariales (Ascomycota, Fungi). Molec. Phylogen. Evol. 35: Mirza J.H. & Cain R.F., Revision of the Genus Podospora. Can. J. Bot. 47: Muroi T., Udagawa S. & Otani Y., Some coprophilous Ascomycetes from Peru. Studies on Cryptogams in Southern Peru. H. Inoue ed. Richardson M.J., Diversity and occurrence of coprophilous fungi. Mycol. Res. 105 (4): Richardson M.J. & R. Watling, Keys to fungi on dung. British Mycological Society. Soláns M.J., Novedades para la micoflora coprófila española, II: el género Podospora Ces. (Sordariaceae). Anales Jard. Bot. Madrid 41 (2): Wang Y.-Z., New records of coprophilous Pyrenomycetes from Taiwan (I). Trans. Mycol. Soc. R.O.C. 7 (3-4): Wang Y.-Z., The genus Podospora in Taiwan. Mycotaxon 76: LEGEND OF THE FREEHAND DRAWING a = perithecia; b-f = peridium (b = endostratum; c = exostratum; d = exostratum at the neck; e = swollen, scattered to agglutinated hairs; f = hyphoid hairs); g = immature spore; h = mature spores; i = jacket-paraphyses; j = ascus with eight mature spores. LEGEND OF THE COLOUR PHOTOS 5

6 1) Spores at different stages of maturity. 2) Perithecium. 3) Peridium (longitudinal section). 4) Scale of agglutined hairs (neck base). 5) Ascus with four mature and four immature spores. Scale bare : photos 1, 2, 5 = 100 µm photos 3, 4 =10 µm. 6

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