Fern Gazette

Fern Gazette

1/ � THE FERN GAZETTE � � \\ ri Edited by loAoCrabbe MoGibby &: BoSoParris THE BRITISH PTERIDOLOGICAL SOCIETY i11 �\ Volume 13 Part 1 1985 The Bri tish Pteridological Society THE FERN GAZETTE VOLUME 13 PART 1 1986 CONTENTS Psge MAIN ARTICLES A reappraiaal of Dryopteris affinis aubap. borreri var. robuste and new records of D. affinis aublpaciea in aastarn Europe - S. Jessen lsolating mechanisma in four Himalayan Dryopteris apeciea - D. S. Loyal 7 Anomalout fronde and venation in Polybotrya cervina - T. G. Walker 13 Cytology and taxonomy in Woodaiaceae - Y.-L. Ma 17 Ecological oblervationa on the pteridophyte flora of Lantang National Park, central Nepal - V. L. Gurung 25 Nisterika, a new genua of Polypodiaceae from Silent Valley, aouth lndia - 8. K. Nayar, P. V. Madhusoodenen & M. J. Molly 33 The generic identity of Polypodium bensense - W. L. A. Hetterscheid 43 The pteridophyte herbarium of Trinity College Dublin - J. Pernell 47 'Sporophyll-pteryx' in African and American Selaginelle - N. auensah & 8. A. Thomas 49 Asplenium punjebense ap. nov. and ita aignlflcanca for the etatue of Ceterech and Ceterechopsis - S7 S. 8ir, C. R. Freser-Jenkins & J. D. Lovis 53 SHORT NOTE Cyrtomium felcstum in Ireland - J. P. Cullinsne & C. Crowley 42 BRITISH PTERIDOPHYTE RECORDS 52 REVIEW 46 (THE FERN GAZETIE Volume 12 Part 6 was published on 5th October 1984) Published by THE BRITISH PTERIDOLOGICAL SOCIETY, c/o Department of Botany, British Museum (Natural History), London SW7 580 ISSN 0308--0838 Metloc Printers Lid., Old Station Road, loughton, Euex FERN GAZ. 13(1) 1985 A REAPPRAISAL OF DRYOPTERIS AFFINIS SUBSP. BORRERI VA R. ROBUSTA AND NEW RECORDS OF D. AFFINIS SUBSPECIES IN EASTERN EUROPE S. JESSEN Arktisch-alpiner Garten und Herpetalogische Versuchsstation, Schmidt-Rottluff-Strasse 90, P.B. 29-07, DDR-9083 Kari-Marx-Stadt, East Germany ABSTRACT Dryapteris affinis var. rabusta is confirmed as being a variety of subsp. barren· as Dryapteris affinis (Lowe) Fraser-Jenkins subsp. barren· (Newman) Fraser-Jenkins var. rabusta (Oberholzer & von Tavel ex Fraser-Jenkins) Fraser-Jenkins & Salvo. Localities for var. barreri and var. rabusta are listed from the author's collections in East Germany, Bulgaria, Czechoslovakia and Romania. lri addition to subsp. barren; subsp. stilluppensis also occurs as a rarity in Thuringia and Bulgaria. ln the Northern Fagaras mountains of southern Romania var. splendens was found in addition to var. borren· and var. rabusta; this is so far only published from Switzerland though Fraser-Jenkins (1982) suggests a wider range and states that it may be expected elsewhere. The diploid subsp. affinis var. disjuncta, known from Switzerland, West Germany, Austria and ltaly, was also found in southern Romania, thus agreeing with Fraser-Jenkins' statement (pers. comm. 1984) that he has also found it in Britain Spain, Portugal and France and expects it to occur anywhere throughout the range of subsp. affinis in sufficiently sheltered places. INTRODUCTION Fraser-Jenkins (1980, 1982) and in Dostal et al. (1984) has recognized in Europe (including Turkey and the Caucasus) the following subspecies and varieties of Dryapteris affinis (Lowe) Fraser-Jenkins: D. affinis subsp. affinis var. affinis var. azorica Fraser-Jenkins var. disjuncta (Fomin) Fraser-Jenkiris var. punctata Oberholzer & von Tavel ex Fraser-Jenkins subsp. barreri (Newman) Fraser-Jenkins var. barreri var. pseudadisjuncta (Oberholzer & von Tavel) Fraser-Jenkins var. splendens (Ehrler) Fraser-Jenkins subsp. rabusta Oberholzer & von Tavel ex Fraser-Jenkins subsp. stilluppensis (Sabranski) Fraser-Jenkins Recent information about various of the subspecies and varieties is also given by Eschelmüller (1972), Schneller (1974), Eschelmüller & Schneller (1980) and Reichstein (1983). Between the years 1975 and 1 984 populations of D. affinis in East Germanywere studied by the author. Material of this species was also collected in Czechoslovakia, Romania and Bulgaria. ln the populations studied subsp. barreri and the taxon described as subsp. rabusta are the most frequently occurring subspecies of D. affinis. TH E STATUS OF SUBSP. ROBUSTA Whereas subspp. affinis, stil/uppensis and barreri are usually relatively easy to differentiate, distinction between subsp. barren· and subsp. rabusta is often difficult (as mentioned by Fraser-Jenkins 1 982) and arbitrary and there does not appear tobe a clear dividing line between them. From the following observations it appears that the status of the taxon rabusta as a subspecies of D. affinis distinct from subsp. barren· is incorrect and it should be a variety of subsp. barreri (and see also Table 1 ). 2 FERN GAZETTE: VOLUME 13 PART 1 (1985) TABLE 1. var borreri var. robu sta Features of leaves somewhat coriaceous, .± thick or leaves herbaceaus to coriaceous, distinction somewhat thin, mid- to light green; mostly relatively thin, mid- to yellowish when young; �innule lpinna­ light green; yellowish when lobes) -apices marked ly squarely young; pinnule-apices rounded, truncate, usually with entire or acute or subacute, if truncate shallowly, squarely-lobed sides, the then only near the frond apex, apices of the pinnules bearing .± lang mostly with markedly incised acicular teeth altenIonger at the to lobed, occasionally undu late corners of the pinnule apices; indusia sides, theIobes being .± square, vary ing from relatively !arge at least the apices of the pinnules bear ing when young, to small, thick or thin .±lang acicular teeth; indusia lbut never as thick as in subsp. affinis), relatively small and thin, mostly sliJ:Jhtly brown to grey, Iifting and light grey, an ripening Iifting shrivelling somewhat an ripening, alten and shrivelling markedly, mostly deciduous, usually with some be ing deciduous. persistent. habitat ln Europe widespread throughout the same as var. barren: many habitals and altitudes; in East Germany occurs most frequently in Fagus and Fagus-comb,ned forests. distribut1on across the whole area of the species, the same as var. borreri. except for all of Macaronesia IAzores, Maderia and Canaries), and rare in Portugal. Th_e present author has collected if in Bulgaria, Czechoslovakia, Romania and East Ge rmany. Frase r· Jenkins 11982) gives the whole range of the subspecies wh ich is the same as that of the variety, based on his collection I in BM) and herbarium spec1mens seen. - The two taxa are dist inguishable only by the greater degree of lobing of the pinnules, the Ionger and more luxuriant pinnules and the !arger frond of subsp. rabusta (see Fraser-Jenkins 1980, 1982 and in Dostal et al. 1984); such features are of the type that may also occur in larger, better developed specimens of a single species as a result of greater growth. - in spite of the relatively good separation between typical and well-developed plants of subsp. rabusta (which are very frequently mistakenly identified as Dryapteris x tavelii Rothm.) and smaller or medium-sized subsp. barren· (also fairly often misidentified as D. x tavelii}, transition forms between the taxa may be found in many populations, particularly those occurring partially in shade and partially in the open. - Subsp. rabusta and subsp. barren· appear not to occur growing together as distinctly separated taxa in the same habitat, but always to be connected by the intermediates mentioned. - Cultivation of both taxa in approximately the same growing conditions show that the frond morphology of both taxa is able to approximate so nearly that it is difficult or almost impossibly artificial to teil one from the other. - Subsp. rabusta appears to be found dispersed throughout almost the whole range , of the species (except Macaronesia and parts of North West Spain and Portugal) and in particular mirrors the range of subsp. barren· (see Dostal et al. 1984). Fraser- DRYOPTERIS AFFINIS IN EASTERN EUROPE 3 Jenkins (pers. comm. 1984) adds that this is even more markedly obvious on a local Ievei, particularly in Spain and Portugal where subsp. barreri is less common than it is elsewhere. - Although requiring more study it seems fairly certain that the Iack of pairing of chromosomes in the 16-celled sporangia resu lting from the combination of different genomes present in subsp. rabusta is the same as that in subsp. barren· (see Fraser-Jenkins 1982). whereas subsp. rabusta and subsp. barren· show different pairing behaviour from subsp. stilluppensis (which shows approximately equal numbers of bivalents and univalents in 16-celled sporangia); subsp. affinis differs in being diploid. Fraser-Jenkins (1982) has hirnself come to the conclusion that subsp. rabusta merely represents luxuriant plants of subsp. barren� and is probably best treated as a variety; he also considers this, and the other varieties treated for the purpose of Dostal et al. (1984) tobe of little taxonomic importance, whereas the subspecies are far more ' significant. He points out (pers. comm. 1984) that intermediates occur between the varieties. and that the variation appears to arise from habitat differe nces. state of development of the plant and random variation genetically fixed by apomixis. Recently, Fraser-Jenkins and Salvo (1984) have made the new combination Dryapteris affinis subsp. barrera var. rabusta (Oberholzer & von Tavel ex Fraser-Jenkins) Fraser�Jenkins & Salvo. Although the subspecies are of considerable taxonomic significance. neither the present author nor Fraser-Jenkins (per. comm.) agree with Holub (1984) who continues to treat D. pseudamas (Woll.) Holub & Pouzar as a species, while ignoring subsp. stilluppensis. He also combines subsp. rabusta as a subspecies of D. pseudomas which presumably arose from following Fraser-Jenkins' original erroneous publication. lt seems likely that Holub has nÖt rea lised how wide-spread subsp. affinis is in Europe and that it was previously included under 0: pseudamas, or that he is not familiar with the three subspecies, which are sufficiently close that many botanists cannot identify them as yet. lt is worth noting that Fraser-Jenkins (pers. comm.) also found subsp. stilluppensis in Czechoslovakia (Boscovice, N of Brno, CRFJ 4989, 15. 7.1976) and it is at present impossible to exclude the occurrence there of subsp. affinis as a rarity.

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