Notes on British species of Octospora

175

Mycol. Res. 100 ( 2 ) : 175-178 (1996) Printed in Great Br~tain

Notes on British species of Octospora

Y.-J. Y A O ~AND , ~ B. M. S P O O N E R ~ 'Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AE, U.K. School of Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF. U.K.

Notes on the taxonomy and nomenclature of British taxa referred to Octospora and Neottiella are presented, based on an examination of herbarium collections and literature. Twelve species are recognized in Octospora. A collection differing from the typical variety of Octospora melina in fruiting period and host moss is reported. Neottieila microspora is considered to be a nomen dubium. It is established that there is no sound basis for the inclusion of Octospora coccinea, 0. convexula, 0 . ithacaensis and 0 . neglecta in the British list. Octospora vivida is placed in synonymy with 0 . rutilans, which is considered to exhibit broad variation in ascospore ornamentation, and 0 . roxheimii var. aestivalis is not considered to merit infraspecific distinction; 0. roxheimii has a wider ascospore size range than described in its protologue.

Although Octospora Hedw. is a long established genus, its delimitation is still in dispute, and species concepts remain to some extent unclear. The genus is characterized by apothecia occurring in association with mosses and having ellipsoid, sometimes ornamented, guttulate spores. The hyphal structure of the apothecial margin is a further distinguishing character of typical members of the genus. Some species, previously referred to Neoftiella (Cooke) Sacc. and still maintained as generically distinct by some authors, have apothecia bearing thick-walled, colourless hairs. Neoftiella was placed as a synonym of Ocfospom by Caillet & Moyne (1987), by combination of the lectotype species, N . albon'ncta (Berk. & Curt.) Sacc. British species of Neottiella have been previously combined in Ocfospora by Dennis & Itzerott (1973) in their treatment of European species of that genus. Twelve species are here recognized as British: 0. alpestris (Sommerf.)Dennis & Itzerott, 0 . crosslandii (Dennis & Itzerott) Benkert, 0 . hefieri (Boud.) Dennis & Itzerott, 0 . humosa (Fr.) Dennis, 0. leucoloma Hedw., 0. melina (Velen.) Dennis & Itzerott, 0 . musci-muralis Graddon, 0. roxheimii Dennis & Itzerott, 0 . rubens (Boud.) Moser, 0. rusfica (Velen.) J .Moravec, 0 . rutilans (Fr.) Dennis & Itzerott, and 0 . fetraspora (Fuckel) Korf. Octospora pilifera (Cooke) K. B. Khare & V. P. Tewari is retained in the British list but its presence here requires confirmation. A key to distinguish these species is given below. Other British records of Octospora and Neoftiella (Cannon, Hawksworth & Sherwood-Pike, 1985), and the nomenclature of some of the recognized species are also considered.

NeottieIla ovilla var. flavodisca Cooke & Massee in Grevillea 2 1 : 71 (1893). This name was listed as a synonym of Neoftiella polytrichi (Schumach.) Massee by Massee (1895), and was considered as a synonym of either Peziza rutilans Fr. or Neoftiella polytrichi by Ramsbottom & Balfour-Browne (1951). It is placed as a synonym of Neotfiella rufilans in Cannon ef al. (1985), as also concluded by Rifai (1968). Re-examination of the holotype ('Ben Lawers, at 2,500 feet elevation', K) confirms this view (but see comments below under 0 . vivida (Nyl.) Dennis & Itzerott).

Neottiella microspora Cooke & Massee in Grevillea 2 2 : 44 (1893). The type of this species, from Scarborough, Yorkshire, 'on a dunghill', has not been preserved (Dennis, 1971). Furthermore, no voucher material can be located for the record of this species in Clark (1980).According to the protologue, apothecia were up to 1 cm diam., with a greenish sulphur disc, short, flexuous, colourless hairs and smooth, ellipsoid spores 7.0 x 3.5 pm. The name seems likely to have applied to an immature specimen, perhaps of a Cheilymenia, but its identity can no longer be satisfactorily resolved and the name should, therefore, be regarded as a nomen dwbium.

Octospora coccinea (P. Crouan & H. Crouan) Brumm. in Persoonia, Suppl. 1: 213 (1967).

This species must be regarded as of doubtful occurrence in Britain. There is no British material in K, and its inclusion in

British species of Octospom Cannon et al. (1985) was apparently based on discussion in Dennis (1978), which made no reference to British collections.

Octospora convexula (Pers.: Fr.) L. R. Batra, in Batra & Batra in Kans. Univ. Sci. Bull. 4 4 : 167 (1963). Pezim convexula Pers., Obs. Mycol. 2 : 85 (1799): Fr., Sysf. Mycol. 2 : 73 (1822). Humaria convexula (Pers.) QuClet, Enchir. Fung. - : 288 (1886). This species was accepted in Cannon et al. (1985) under both Hurnaria Fuckel and Ocfospora, but appears, in fact, to belong to neither genus, Although Rziza convexula was combined in Ocfospora by Batra (Batra & Batra, 1963), he had evidently not studied Persoonrs type. According to Dennis & Itzerott (1973), the type of Pezim convexula is not an Octospora. Unpublished drawings and notes by Dennis on a collection from Herb, persoon (in Herb, Lugd Bat No. 910261-233, L) show apothecia to have multisporous asci and hymenium deep blue in Reagent and indicate that the fungus is lichenized. It presumably belongs in Lecanorales, although its generic position is unclear. This species has been reported from Britain by various authors (see Ramsbottom & Balfour-Browne, 1951; Cannon ef al., 1985). However, specimens so named are probably referable to taxa, e.g. two British collections under 0.

convexula in K were redetermined by Dennis as 0. rubens. Octospora crozalsiana GrPlet in Bull. Soc. M y c . Fr. 4 1 : 83 (1925). This was reported from Britain by Comer (1929) but is a synonym of Octosporella jungermanniarum (p. Crouan & H. Crouan) Dobbeler according to Dobbeler (1978, 1980).

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Odospora ithacaensis (Rehm) K. B. Khare in N o m . J. Bat. 2 2 : 111 (1975).

Humaria ithacaensis Rehm in Ann. Mycol. 2: 35 (1904). Neoftiella ifhacaensis (Rehm) Schweers in Rev. Mycol. 10:6 9 (1945). This species is listed in Cannon et al. (1985) under Neoftiella, on the basis of a specimen in K determined by Le Gal. Examination of this specimen (Yorkshire~ Pickerin& Kingthorpe, On heavy mOsses~ September G. Bramley) shows that thick-wa11ed hairs are present on the apothecia, which is not a character of the type of 0 . ithacaensis 'edescribed by Khare (1975). The a~Otheciain the YOrkshire 'pecimen are mm diam., cupulate, with disc yellow to light orange when dried. The hairs are 90-220 x 10.0-13.0 vm, colourless to pale yellow, 19701

*.

'lightly obtuse at the 3-4-se~tate 2.0-3.0 vm thick, often with a bulbous base, and superficial. Ascospores ellipsoid to cylindric-ellipsoid with rounded ends, 16'5-20'0 8'0-9'5 eguttulate Or containing One guttule, ornamented with fine warts. The specimen may belong in Cheilymenia rather than Octospora, but requires further study to make a positive determination. Khare (1975) shows that the type of 0 . ifhacaensis has small apothecia ( < mm diam.) without hairs and ascosPores biguttulate. Khare's (1975) combination is supported by Dobbeler (1980).

Octospora melina (Velen.) Dennis & Itzerott in Kew Bull. 2 8 : 16 (1973).

Humaria melina Velen., Monogr. Discomyc. Bohem.: 325 (1934). This is a well documented British species having apothecia

Key to British species of Octospora (measurement of the ascospores excluding ornamentation) . . . 2 . . 1. Ascospores smooth or very finely punctate, usually appearing smooth under the light microscope . 1. Ascospores with prominent warty or reticulate ornamentation . . . . . . . . . . 12 2. Apothecial excipulum comprising angular to globose cells, cells becoming smaller towards the margin; ascospores ellipsoid to . . . . . . . . . . . . . .0.pilifera broadly ellipsoid, 13.5-19.5 x 9.5-13.0 pm 3 2. Apothecial excipulum comprising woven hyphae, often becoming parallel towards the margin; ascospores various . 3. Asci predominantly 4-spored, occasionally up to 6-spored; ascospores narrowly ellipsoid to ellipsoid (24.0-) 26.0-30.0 x (8'0-1 . . . . . . . . . . . . . . . . . . . 0. 9.5-11.0 pm tetraspora . . . 4 3. Asci normally 8-spored; ascospores various . . . . . . . . . . . 4. Ascospores irregularly biseriate or crowded in upper part of the ascus . . . . . . . . . . 5 . . . . . . . . . . . . . . 6 4. Ascospores predominantly uniseriate in the ascus . . . . . . . . . . 5.Ascos~oresellipso-cylindric,20~0-28~0x8~0-10~5pm. 0.musci-muralis . . . . . . . . . . 0 . leucoloma 5. Ascospores broadly ellipso-hsoid, 18.0-25.5 x 100-12.5 . 0.hetieri 6. Apothecia clothed with stiff, tapered hairs forming a fine marginal fringe; in association with Funaria or Ceratodon . . . 7 6 . Apothecia lacking stiff, tapered, marginal hairs; in association with various mosses . . . . . . . 8 . . . . . . 7. Ascospores mostly shorter than 17.0 Urn, never greater than 18.5 pm long . . . 9 . . . . . . . . . 7. Ascospores longer than 1 7 0 pm, often over 20.0 M m . , . . 0.rubens 8. Asci 15.0-19.0 pm broad; ascospores 15.0-18.5 x 9.5-12.0 prn . . . . . . . , . . 0.rustica 8. Asci 11Q-15,0 pm broad; ascospores 13.0-16.0 x 90-11.0 pm . . . . . . . . . . 0.humosa 9. Apothecia 3-10 mm diam., associated with Poiyirichum; ascospores often finely punctate . . . . . .10 9. Apothecia usually less than 3 mm diam., associated with other mosses; ascospores smooth . . . . , 0.roxheimii 10. Ascospores 195-23.0 (-270) x 12.5-16.0 pm; apothecia in association with Funuria . . . . 11 . . . 10. Ascospores mostly narrower than 12.5 ~ m apothecia : in association with other mosses . . 0. crosslundii 11. Apothecia with slightly developed sterile margin, associated with Barbula, fruiting in summer and autumn 0. leucolornu 11. Apothecia with prominent sterile margin, usually associated with Bryum, fruiting in winter and spring . . . 12. Apothecia clothed with hairs 100-330 pm long; ascospores 21.0-290 x 12.0-15.5 pm, ornamented with isolated warts, short . . 0. rutilans . . . . . . . . . . . . . . ridges, or a reticulum . . . 13 12. Apothecia lacking hairs; ascospores 13.0-200 x 7.5-13.0 pm, ornamented with isolated warts . . . . 0. alpestris . . . 13. Asci initially 8-spored, the lower four spores aborting; ascospores 13.0-190 x 7'5-10.0 pm . . 0. melina . . . . . . 13. Asci with 8 fully developed spores; ascospores 15.0-200 x 11.0-12.0 pm .

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Y.-J. Yao and B. M. Spooner which develop in the autumn in association with Cerafodon, Pohlia, Dicranella and Africhum (Dennis & Itzerrott, 1973). A collection which is morphologically similar to the typical variety, but which differs in host genus of mosses and fruiting season, is reported here from British material. Apothecia 1-3 mm diam. when dried. Disc concave, orangeyellow to reddish-orange. Receptacle cupulate, concolorous externally, margin with obtuse, colourless hyphae, 7.012.0 ym diam.; basal hyphae colourless, flexuous, 6.08.0 ym diam., walls thickened to 1.0-1.5 (-2.0) ym, septate, with thin septa. Ectal excipulum composed of thin-walled, irregular prismatic cells, mostly 20.0-40.0 x 120-18.0 ym, more elongate to ca 50 ym long towards the margin. Medullary excipulum of thin-walled, woven hyphae, 7.0-12.0 ym diam. Asci I-, cylindric, tapering towards the base, 200250 x 16.0-18.0 (-20.0) ym, 8-spored, spores uniseriate. Ascospores ellipsoid to broadly ellipsoid, 17.0-20.0 x 11.013.0 pm, containing 1 (-2) guttules, ornamented with warts 0.5-1.5 ym across, ca 0.5 ym high. Paraphyses straight or sometimes strongly curved above, enlarged to 4.5-6.5 ym diam. at the apex. Specimen examined: Wales, Dyfed, Pembrey, Cefn Sidan Beach,

18.0-23.0 x 12.5-15.0 ym. A sheet with 58 spore drawings and measurements (as ' 17.5-24.4 x 13.0-16.3 ym'), prepared by Itzerott, is preserved with the type in K. We consider that British collections are conspecific with 0. roxheimii and that the species exhibits spore dimensions greater than given in the protologue. Octospora roxheimii var. aesfivalis was considered distinct from the typical variety only in ascospore size, 20.025-0 x 12.5-15.0 ym (Caillet & Moyne, 1987). However, judged from material examined here, there is a continuum with regard to ascospore dimensions and no such distinction can be justified. The species concept should be emended to include a greater ascospore size range, and the name 0. roxheimii var. aestivalis reduced to synonymy.

Octospora tetraspora (Fuckel) Korf in Mycologia 46: 838 (1955).

Ascobolus fefrasporus Fuckel, Fungi Rhen. Fasc. 19, No. 1856 (1866).

Humaria fefraspora (Fuckel) Sacc., Syll. Fung. 8 : 121 (1889). Byssonectria fetraspora (Fuckel) Korf in Phytologia 2 1 : 202 (1971).

amongst small moss (Byum) on sandy soil at edge of beachldunes, 7 December 1991, P. A. Jones (K(M) 18724, K).

This species is listed under Byssonecfria P. Karst. in Cannon ef al. (1985). The species is retained in Ocfospora by Dennis &

Differences in fruiting period (December to February) and host moss (Grimmia) have been employed to distinguish 0. melina var. meslinii (Le Gal) Dennis & Itzerott from the typical variety of this species (Dennis & Itzerrott, 1973; Dennis, 1978). The collection described above apparently resembles 0. melina var. meslinii in fruiting season, but differs in moss host. What, if any, significance should be placed on this difference is at present unclear.

Itzerott (1973), which, on the basis of excipular structure and association with the moss Bryum argenteurn (Dennis & Itzerott, 1973), seems a more appropriate position (see also Pfister, 1993; Yao & Spooner, unpublished).

Octospora neglecta Dennis & Itzerott in Kew Bull. 2 8 : 16 (1973). The British record of this species (Cannon ef al., 1985) is apparently derived from the comments by Dennis (1978), who did not explicitly refer to any British collection. There appear to be no other published British records of this species. No British material has been seen in the present study and the species should be deleted from the British list.

Octospora roxheimii Dennis & Itzerott in Kew Bull. 2 8 : 17 (1973). Octospora roxheimii var. aesfivalis Caillet & Moyne in Bull. Soc. Myc. Fr. 103: 210 (1987). The ascospore dimensions of this species were given in the protologue as '17-20 x 13-15 ym', possibly measured from young ascospores. Three British collections under this name show spore size range 19.5-24.5 (-27.0) X 125-16.0 Dm (England, Berkshire, Windsor Forest Park, 9 November 1973, D. A. Reid, K), 20.0-24.0 (-27.0) x 13.0-16.0 Dm (England, Sussex, Petworth, Petworth Park, 27 July 1991, M. Gregory, K) and (20.0-) 22.0-26.0 (-28.0) x 13.0-16.0 ym (England, Surrey, Kew, bank of River Thames, 31 May 1993, T. Laessere, K). Examination of the type material, which has only a small piece of apothecium remaining, shows it to have ascospores

Octospora vivida (Nyl.) Dennis & Itzerott, Kew Bull. 2 8 : 20 (1973).

Peziza vivida Nyl. in Flora 4 8 : 467 (1865). Neoftiella vivida (Nyl.) Dennis, British Cup Fungi: 28 (1960). This species has been distinguished from 0 . rutilans solely on the basis of ascospore ornamentation. Typical 0. vivida has ascospores ornamented with isolated warts rather than a reticulum under the light microscope. However, examination of material referred to each of these names consistently shows variation in spore ornamentation from isolated warts to partly interconnected warts, to broken reticulum or complete reticulum within a single apothecium. Although the proportion of spores with isolated warts to those with reticulate ornamentation varies, we conclude that these names represent extremes of a single taxon, for which the earlier name is 0 . rutilans. We wish to thank Professor D. L. Hawksworth for critical reading of the manuscript, and Mr C. Townsend for identification of moss host of the collection reported under Ocfospora melina. This work is funded by a grant (CR3/8284) to the project 'The Ascomycetes of Great Britain and Ireland' from the Natural Environment Research Council.

REFERENCES Batra, L. R. & Batra, S. W. T. (1963). Indian discomycetes. University of Kansas Science Bulletin 64, 109-256. Caillet, M. & Moyne, G. (1987). Contribution a I'etude du genre Odospora Hedw. ex S. F. Gray (Pezizales). Esphces i spores elliptiques ou fusiformes. Bulletin Trimestriel de la Soribti Mycologique de France 103, 179-226.

British species of Octospora Cannon, P. F., Hawksworth, D. L. & Sherwood-Pike, M. A. (1985). 7'he British Ascomycotina, an Annotated Checklist. Commonwealth Agricultural Bureau: Slough, U.K. Clark, M. C. (1980). A Fungus Nora of Warwickshire. British Mycoiogical Society: London. Comer, E. J. H. (1929). A Humariaceous fungus parasitic on a Liverwort. Annals of Botany, London 43, 491-505. Dennis, R. W. G. (1971). New or interesting British microfungi. Kew Bulletin 25, 335-374. Dennis, R. W. G. (1978). British Ascomycetes. J. Cramer: Vaduz, Liechtenstein. Dennis, R. W. G. & Itzerott, H. (1973). Octospora and Inermisia in western Europe. KPw Bulletin 28: 5-23. Dobbeler, P. (1978). Moosbewohnende Ascomyceten. 1. Die Pyrenocarpen, den Gametophyten besiedelnden Arten. Mitteilungen der Botanischen Staatssammlung Miinchen 14, 1-360.

(Accepted 24 June 1995)

178 Dobbeler, P. (1980). Untersuchungen an moosparasitischen Pezizales aus der Verwandtschaft von Octospora. Nova Hedwigia 31, 817-864. Khare, K. B. (1975). On Humaria ithacaensis. Norwegian ]oumal of Botany 22. 111-113. Massee, G. (1895). British Fungw Flora. A Classified Text-book of Mycology, 4. George Bell & Sons: London. Pfister, D. H. (1993).A synopsis of the North American species of Byssonectria (Pezizales) with comments on the ontogeny of two species. Mycologia 85, 952-962. Ramsbottom, J. & Balfour-Browne, F. L. (1951). List of Discomycetes recorded from the British isles. Transactions of the British Mycologicai Society 34, 38-137. Rifai, M. A. (1968). The Australasian Pezizales in the Herbarium of the Royal Botanic Gardens, Kew. Verhandelingen der Koninklijke Nederlandsche Akademie van Wetenschappen, Afdeeling Natuurkunde 11, 57(3), 1-295.