A Revision of the Generic Limit Between Clitocybe and Lepista

Home , Clitocybe nebularis, Lepista, Ripartites

A revision of the generic limit between Clitocybe and Lepista

Harri Harmaja Botanical Museum, University of Helsinki, SF-00170 Helsinki, Finland

HARMAJA, H . 1974: A rev1swn of the generic limit between Clitocybe and Lepi&ta. - Kars.tenia 14: 82-92. - On the basis of various spore characters, some already no1ed but partly neglected (e.g. cyanophilic spore wall) and some »new», it is concluded that Lepista (Fr.) W . G. Smith ( Agaricales) is a valid genus, and independent of Clitocybe (Fr.) Staude. The current concept of Lepista is, however, somewhat altered, since the genus is considered to include species with smooth (under the light microcope) and deep yellow spores. The inclusion of the Clitocybe gilva group in Lepista is also considered justified. The essential characters of the amended genus Lepista are given, of which the strongly cyanophilic spore wall and the presence of a remarkable proportion of collapsed spores are emphasized. It seems that the type of Lepista, viz. Agaricus lepista Fr., can probably be appropriately typified, so that for the fungi concerned the generic name Lepista i& thus indeed correct and available. Some other nomenclatural remarks are also made. Two new combinations are made in Lepista, the species in question having previously been referred to Clitocybe (the first of these even being one of the most famous species of that genus) : Lepista nebularis (Fr.) Harmaja and Lepista subalpina (Big. & Smith) Harmaja.

1. In traduction 1937, if, in agreement with SINGER (1962), that sectional name is considered to Recently BIGELOW and A. H. SMITH ( 1969) have been validly published. The classi amalgamated the agaric genus Lepista (Fr.) cal differences, much emphasized by SIN W. G. Smith 1870 ( = Rhodopaxillus Maire GER (e.g. 1962 ), between Clitocybe and 1913) with Clitocybe (Fr.) Staude 1857 as Lepista lie in the spores. In the former genus a new section, Clitocybe sect. V erruculosae they are said to be white, yellow or pale Big. & Smith. They unfortunately fail to give pinkish in mass, and normally smooth; if the author citation of Clitocybe, but this they are not smooth, then they are supposed treatment must indicate that they, too, to be always white in print. In Lepista the approve STAUDE instead of KuMMER as the spores should be pale pinkish in deposit, author who elevated the Friesian tribe to the and always more or less roughened. BIGELOW generic status, since if KuMMER with his 1871 and SMITH ( 1969 ) considered these classical paper were preferred, the generic name Le features and concluded that there is no pista would have priority of one year over difference of generic degree between the Cli Clitocybe sensu BIGELOW & SMITH. Anyway, tocybe and Lepista species. Some Clitocybe the name of their new section is illegitimate, species have spores which, though white being superfluous, as they include in it Le (some of these observations on colour may be pista nuda, which is the type of Rhodopa vitiated by too thin a deposit) are rough xillus sect. Genuinae Konr. & Maubl. 1924- with an ornamentation similar to that found

82 in Lepista, while some have spores which, paper on the Fennoscandian Clitocybes though smooth, are pale pinkish as in Le (HARMAJA 1969 ), I began to use the heated pista. They also pointed to the existence of cotton blue techniques (see KoTLABA & Pou Lepista species with extremely low warts on ZAR 1964) in Agaric al es taxonomy, a meth their spores. Their conclusion is further od with which I became acquainted during supported by the fact that in Le pista (at studies on Discomycetes. Among many other least in L. irina) the same gills may pro interesting things, I observed that in the duce smooth (under the light microscope) »classical» species of L epista (sensu SINGER spores besides distinctly rough ones and these 1962) studied by me, the spore wall (or some authors even claim that there exists in the of its outer layers), including the warts, is Lepista group a species (C. pseudoirina Big. strongly cyanophilic. In very young spores & Smith) with only smooth spores, in which it is stiH cyanophobic but it soon begins delicate verrucae are visible only in electron to absorb the dye, the mature and old micrographs. spores staining darkest blue. The wall in Indeed, if the combination of pale pinkish the hilar appendix seems, however, to be spore colour and a roughened spore wall were cyanaphobic (unless very weakly cyano in fact the only thing separating Lepista from philic? ). The species studied were : L. irina, Clitocybe, the amalgamation performed by L. luscina, L. nuda, L. rickenii, L. sor these American authors would be understand dida, C. subalpina Big. & Smith (which able. Like BIGELOW and SMITH, I was will be formally transferred to Lepista later dissatisfied with the common practice of in this paper), L. subconnexa, and several separating the Clitocybe gilva group gener others which were impossible to identify. ically from the Lepista species (HARMAJA Subsequently it was found that the cya 1969), but I was unwilling to accept their nophilic spore wall of L epista was by no solution to this problem. Instead, I suggested means unknown in the literature, since that this group should be included in Lepista, LAMOURE & FICHET ( 1962 ) remark, as a mere irrespective of the colour of the spores in detail, that the spore wall of a Lepista species the species of this group (which, anyway, they call »Rhodopaxillus densifolius Favre» was always pinkish in those specimens I stains intensely in »Bleu lactique» ( = cotton studied). blue) . KuHNER ( 1969 ) found the spore wall I am now even more convinced that Le of L. irina to be cyanophilic, BEssoN ( 1970), pista, with some amendments , is a valid another member of the skilful French school, genus, and thus take quite the opposite view mentioned that the same applies to the spore to that of BIGELOW and SMITH, even though wall and its ornamentation in L. irina and the classical differences do not always apply L . luscina (called L . panaeola), and finally in the distinction between Lepista and Cli SINGER ( 1972) made the same observation tocybe. The reason is that during my con as regards L. ameliae, L . argentina, L. densi tinued studies in and around Clitocybe I ob folia, L. irina, L. nuda, L. sordida and L. served two obviously diagnostic characters subconnexa. for separating these genera, neither of which The other character which seems to possess have been mentioned by the two American great diagnostic value is that a considerable · authors (BIGEI;OW & SMITH 1969). The pro portion of Lepista spores (especially the present contribution also includes some other immature ones still attached to the sterig taxonomical and nomenclatural notes as well mata) constantly have strikingly shrunken, as some neglected observations from the lit or collapsed walls, being almost or complete ly without contents. I have so far mostly erature. Acknowledgements. - I am indebted to Dr. made this ob~ervation on water, :Melzer, Robert L. Shaffer (MICH ) for placing certain and cotton blue squash mounts, ma:de specimens at my disposal. I am also grateful to of the lamellae of dried basidiocarps, but Mr. Mauri Korhonen for taking t he photographs. occasional observations on the spores of deposits also revealed the presence of col 2. The characters separating Lepista from lapsed spores. Strangely enough, it appears Clitocybe that the literature does not mention this striking phenomenon, apart from my report Immediately after the publication of my on L . subconnexa (HARMAJA 1970) . The

83 reason for this collapse is uncertain. One existing original material is of Agaricus gilvus explanation which suggests itself is that these Pers. ex Fr., consisting of one specimen in the PERSOON herbarium in Leyden, studied by shrunken spores are unripe and for some SINGER (1961) and by me. Sometimes PATOU genetically determined reason have unusually ILLARD is cited as the author who transferred soft walls, which become irreversibly collapsed nhe speci·es to Lepista but RozE's (1876: 110) in drying, especia:l1y as they are mo•re or combination has priority. less devoid of contents (due to their imma A great many other species ascribed to ture stage?). Or, possibly the walls are shrunk Clitocybe and several undescribed ones were en at first in the normal fresh condition, studied. It turned out that (with one im and swell out as the spores receive their portant exception to be treated below in the plasm (and nuclei? ) and become turgid. third section) their spore wall is either com It subsequently appeared reasonable to pletely cyanophobic or only weakly cyano check Clitocybe species for these two char philic, never being collapsed in notable acters, to see whether they might provide a amounts of spores (Fig. 1 a). (It should be distinction between Lepista and Clitocybe at mentioned here that a careful distinction the generic level. I already considered the should always be made between the spore C. gilva group to belong to Lepista, in view wall and spore contents, since the latter are of its distinctly warted and thickish-walled usually more or less cyanophilic.) spores, which are pinkish-tinted in deposit (at Thus it seems that we have attained a least in the various »forms» studied by me) delimitation of Lepista which is more natural (HARMAJA 1969) , and this group did indeed than earlier ones, and at the same time found reveal a strongly cyanophilic spore wall and characters which truly justify according Le ornamentation as well as a conspicuous pro pista the rank of genus, and which also give a portion of collapsed spores. The cyano fairly convenient routine method for telling philic spore wall in this group had, how whether a single specimen belongs to Clitocy ever, already been reported in the literature, be or Lepista. e.g. byKi.iHNER ( 1969) , BESSON ( 1970) , and SINGER (1972). In addition, at high magni 3. Relationship of Clitocybe nebularis to fications under the electron microscope, the Lepista spore ornamentation in C. gilva col!. is seen to be very similar to that present in L epista The species of Clitocybe that forms the (BIGELOW & RowLEY 1968 ). These facts exception mentioned above in section 2, should be final justification of the opinion possessing both a strongly cyanophilic spore held by a small number of workers on agarics wall and a very striking proportion of that C. gilva col!. i.s congeneric with tihe shrunken spores (Fig. 1 b), is C. nebularis classical species of Lepista. In his paper (Fr.) Kumm. I want to emphasize that, mentioned just above, SINGER (1972) has according to my studies, all the 21 other changed his previous opinion and come to species included by me (HARMAJA 1969) in the same conclusion. the type subgenus of Clitocybe had com It may be mentioned here that the taxonomy pletely cyanophobic spore walls, including of the L. gilva group is in urgent need of revi those fleshy species previously always sup sion, and that, to my knowledge, no satisfactory solution has yet been suggested. We may have posed to be dose'ly related to C. nebularis. (All here just one very variable species, or two or 'but one of t'he 11 spe6es of the sections La three, or more. According to my observations, tisporae, Ditopae and Strigipedes of the sub attention should be paid to at least the following genus Pseudolyophyllum also proved to have points: the colours of the fruit body, the hygrophanity of the pileus, the pileus surface cyanophobic spore walls, while those of the when dry (whether distinctly concentrically subgenus Roseospora and the type section of wrinkled or not) , the thickness of the context the subgenus Pseudolyophyllum as well as C. (also at the pileus margin), the exact colour schulmannii of the section Strigipedes, 11 al of the spore deposit, the exact size and shape of the spores (whether subglobose or more or less rogether, possess weakly cyanophilic spore broadly ellipsoid), the kind of spore bas·e, walls). SINGER (1972) also mentions that so the length and distribution of the verrucae of me species of Clitocybe have cyanophobic the spores, and of course the ecological and spore walls, while others possess cyanophilic distributional features. For the present, I recom mend that the name used for this group should be ones. He included C. nebularis among the lat »Lepista gilva (Fr.) Raze coli.», because the ter species, but observed that the cyanophilic

84 a b

Fig. 1. Spores in heated cotton blue squa&h mount, prepaved from dried gills. Bright field, x 1000. Photo by M . Korhonen. - a) Clitocybe gibba (Fr.) Kumrn., the type species of Clitocybe (Finland, EteHi-Hame, Hattula, 25. IX. 1967, H. Harmaja; H). Note the lacrymoid shape and the thick confluent base of the spores, which drift about singly in the mountant and pos&eSiS normal and very thin walLs. The spores ar-e equa!Hy dark throughout (except for some paler oil drops) as their contents are weakly to moderately cyanophilic while the very thin walls are cyanophobic and not discernible. - b) Lepista nebularis (Fr.) Harmaja (Finland, Varsinais Suomi, Lohja, 2. XI. 1967, H. Harmaja; H). Note the principally ellipsoid shape of the obtuse-based spores, which, bestides occurring singly, are also commonly seen in tetrads and dyads (very rarely even thvee adhered together), a part of them, including those immature ones still attached to the sterigmata, having collapsed walls and no contents (three of the four groups on the right repvesenting such spores have been photographed in Melzer's reagent with a lower magnification). The spore waJ!s are thickened and cyanophilic, the borders of the spo res being seen to be darker than their contents. Some of the spore clusters are seen from above. character in this species is weaker than in the the gills, mostly more or less adnate-sinuate, others, in contrast to my results. (Anyway, to be decurrent, and in L. subconnexa at least SINGER does not use my procedure of they are clearly decurrent (BIGELOW & recognizing three categories of matter on the SMITH 1969; HARMAJA 1970). Moreover, basis of its capacity to absorb the dye: ( 1) since the publication of my paper on the weakly cyanophilic, ( 2) moderately cyano Fennoscandian Clitocybes, I have found fruit philic and ( 3) strongly cyanophilic matter.) bodies of C. nebularis with many of the Even in an earlier study (HARMAJA 1969), C. gills somewhat sinuate near the stipe. An nebularis was found to 'Possess certain cha even more important find was my discovery racters which were unique in Clitocybe (a in southern Finland, in the Lohja limestone good proportion of spores collapsed; spore district, of a curious fungus, which was deposit deep yellow; different parts of dried whitish and possessed a non-hygrophanous fruit body unusually rich in chlorine tinges pileus and almost Tricholoma-like, sinuate, under ultra-violet light), and which led me not even slightly decurrent lamellae. When to place it in a different section from the fresh this agaric possessed an odour of C. other fleshy species! As, besides the two very nebularis, not being so fragrant as L. irina, important characters dealt with above, the and gave the impression of a Lepista rather other features of C. nebularis (see below) than that of a Tricholoma. I was very eager also seem to suggest a relationship with Le to see what its spores looked like, and my pista, or at least do not exclude this possibi surprise was great when they turned out lity, this species should be transferred to Le to be completely smooth under the light pista, although its spores are smooth (at least microscope and almost identical with those under the light microscope) and lack a pink of C. nebularis (the size of the hilar appendix ish colour. is slightly different), possessing all the The habit of C. nebularis is distinctly features treated above. Clamp connections clitocyboid, the lamellae usually being were abundant. A spore deposit was unfor completely decurrent, but in the classical tunately not obtained. According to current Lepistas there is a well-known tendency for taxonomy, this species would have keyed out

85 among the clamped Tricholomas! This fun posits in both the bulk of Lepista and in C. gus should of course be included in Lepista, nebularis. together with C. nebularis, being in a way The smooth spores of C. nebularis may at a connecting link between the bulk of L epista first sight seem to exclude it from Lepista. and C. nebularis, as it possesses a Lepista But here I agree with BIGELOW and SMITH habitus but is microscopically extremely close ( 1969 : 165 ), who write about the »futility to C. nebularis. This species, L. singeri Har of trying to use arbitrarily a character such maja (HARMAJA 1974), may help to solve the as spore ornamentation to separate 'natural problem of the »smooth-spored Lepista irina» groups'». The important point is that the of some authors, which others often place in Lepista species and C. nebularis evidently Tricholoma. A new subgenus of Lepista, ba have a homological layer in their spore wall, sed on C. nebularis and L. singeri, will be viz. the strongly cyanophilic one, which gener established (HARMAJA 1974). Generally, ally develops projections ranging from very macroscopic characters, such as the attach small to fairly coarse ones. It should be re ment of the gills to the stipe and the pres membered that even now the smooth ence versus absence of a stipe, or the po spored C. nebularis and L. gilva coil. with sition of the latter, should be used very care verruculose spores are almost uniformly con fully in the generic taxonomy, and only in sidered congeneric, but both referred to Cli connection with other, preferably micro tocybe! It would not be surprising if the spore scopic, features. wall of C. nebularis turned out to be uneven As regards the reactions of C. nebularis under the electron microscope. L. irina may under ultra-violet light, a typical member of be considered a species intermediate between Lepista, L. subconnexa, was observed by the bulk of Lepista on the one hand and me to display a similar and even more C. nebularis and L. singeri on the other, conspicuous chlorine colour in different parts as a part of the spores of L. irina seem of its dried fruit body, and this feature to be smooth under the light microscope, might also be considered evidence of the while the rest of them possess low warts. relationship of C. nebularis to Lepista. BIGE Moreover, it should be pointed out that the LOW and SMITH ( 1969) report that L. sub spores in Lepista and C. nebularis also seem r.onnexa (as Clitocybe s.) and C. phyllophila to be very similar in several respects other appear to be close to each other in all char than the most important ones already men acters but the spore surface. However, I con tioned. The spore wall in C. nebularis is some~ sider a close relationship unlikely, not only what thickened, my latest studies showing it because there are several differences in their to be ca. 0.3-0.4 flm thick (in contrast to spores (e.g., the spore wall in C. phyllophila my earlier opinion), and this feature also is smooth and only weakly cyanophilic ), but suggests relationship with Lepista. In addi because their ultra-violet responses also differ. tion the spore shape, the often depressed Dried basidiocarps of these species may in suprahilar area of the spores, and the spore deed sometimes seem very alike, but they are contents with a distinct oil drop or drops easily distinguished from each other without accord completely with the characters of the aid of a microscope. For instance, under Lepista. ultra- iolet light, with a wave length of 254 Also, the odour, taste and edibility as well nm, the pileus of L. subconnexa is lumi as the ecological and distributional characters nously chlorine coloured, while that of C. of C. nebularis accord very well with the phyllophila remains mat and pale, with some characters of Lepista. violet tinges. In an earlier paper (HARMAJA 1969), I The deep yellow spore colour present in agreed with those who preferred to typify C. nebularis is unknown in Lepista in its the genus Clitocybe with C. nebularis. current concept but I think that it can be Now 1 must change my opinion and sup considered to lie within the amplitude of port those considering C. gibba the lecto variation in spore colour of this genus, where type. A most inconvenient situation would different shades of reddish colour are already arise if my taxonomical conclusions were known (see e.g. BIGELOW & SMITH 1969) . accepted and at the same time C. nebularis The important point is that the spore print were regarded as the type. For instance, is distinctly coloured in sufficiently thick de- the name Clitocybe would replace Lepista

86 and a very great number of new combi turgidity, the sterigmata supporting the nations would be necessary, so that the unripe spores at their tips began to col general principle of stabilizing the nomen lapse and turned towards each other. clature would not be followed. As C. gibba Accordingly in all three spec1es the is also the type of the section I nfundibuli spores, when viewed from above, were formes (Fr.) Sing. & Dig. of Clitocybe, seen to come nearer and nearer to each this well-known sectional name must other, until they finally touched and for inevitably be considered a synonym of the med a cluster of four spores. When com name of the type section, sect. Clitocybe. pletely dry, these same fragments of lamel lae were squashed in Melzer's reagent and 4. The occurrence of spores adhering togeth the mount was observed; two different er m tetrads and the taxonomical signifi cases were seen : the spores of the Agro cance of this character cybe species and those of C. gibba loosen ed readily from t~e sterigmata and also One more interesting but neglected feature from each other, drifting about singly in of Lepista spores is that in all the species the mounting liquid, while the detached studied a certain amount of the spores (in spores of C. odora mostly occurred in cluding the collapsed ones) can be seen to fours and twos, as was of course expected adhere together in tetrads and dyads, e.g. in (HARMAJA 1969) . Thus this peculiar char water, KOH ( 5 %) , Melzer's reagent and acter observed in a major or minor part heated cotton blue, when the mount was of the spores of certain species is perhaps prepared from a piece of dried lamella. The explained in the following way. When proportion of adhering spores in all the de the unripe spores on the sterigmata of tached spores drifting in the mountant may these species come into contact with each be rather small or even more than 50 per cent, other as described above, their undeveloped varying with the species. There does not seem walls or some outer layer ( s) of these are to be any earlier mention of this character gelatinized and sticky, and thus the four in the literature, apart from my observation spores not only touch but cling together concerning L. subconnexa (HARMAJA 1970) . as if glued, continuing to do so even when In the present case this feature is not of the gill tissue is crushed during the pre great diagnostic value at the generic level paration of microscopic slides. The occur (but evidently has significance at the infra rence of spore dyads can easily be generic and suprageneric levels), since it is explained by the cleavage of tetrads and/ present in different groups of Clitocybe or the presence of occasional two-spored (HARMAJA 1969); and, conversely, the occur basidia among the normal four-spored rence of spores adhering together in fours ones. and twos is almost negligible in L. gilva coli. A different situation presumably prevails In this respect, too, the spores of C. nebula in most of the Basidiomycetes, where, ris are typical of Lepista, the majority of although »spore tetrads», as viewed from them being stuck together in this way (HAR above, may be seen in intact dried lamel MAJA 1969) (Fig. 1b) . lae, the spore walls are evidently not sticky, In my paper on the Fennoscandian Cli and the spores are readily separated when tocybes cited above I perhaps did not the basidia are crushed or shaken during make it sufficiently clear that the possible the preparation of microscopic mounts. occurrence of spore tetrads and dyads There may also be species with rigid walls should be studied in squash mounts made in the sterigmata, in which case the latter from a piece of dried lamella. with their unripe spores may not approach My earlier tentative explanation of this each other when drying. phenomenon was subsequently disproved I have observed spore tetrads in the by microscopic studies of fresh, drying species of many other genera besides Cli lamellae of two species with single spores tocybe and Lepista, e.g. Collybia, Lepiota, (C. gibba and Agrocybe cf. dura) and Lyophyllum, Pseudoclitocybe and Rhodo one with tetrads (C. odora). The lamellae cybe, and I Jelieve that this character, were lying free on an object glass, and I which has proved very useful in Clitocybe found that, as the tissue dried and lost its (HARMAJA 1969) , may also be found to

87 possess diagnostic value at different taxono wet habitats or on wood, evidently not form mic levels outside that genus. ing ectotrophic mycorrhiza; distribution cosmopolitan in very variable climatic con 5. The essential characters of the amended ditions. genus Lepista 6. The relationship of Lepista to certain L epista (Fr.) W. G. Smith is thus amended genera to comprise species with the following char acteristics (compare Fig. 1b) : fruit bodies My preliminary studies suggest that other medium-sized to large with a tricholomoid features besides the classical differences dis to clitocyboid habit, and very variable col tinguish Tricholoma and Collybia from L e ours; pileus hygrophanous or not; basidia pista. The two genera, sometimes confused without siderophilous granulation, with in with or supposed to be related to L epista, amyloid, indextrinoid and cyanophobic walls; evidently as a rule have a cyanophobic spore spore print lightly coloured, either pinkish wall, and their spores are generally not con or deep yellow; spores uninucleate (KuHNER spicuously collapsed and mostly (at least in 1945); a major to minor proportion of the Tricholoma) do not occur in tetrads or dyads. spores (especially the immature ones?) stick SINGER ( 1972) also reports the spores of together in tetrads and dyads, at least in wat those species of Collybia and Tricholoma er, KOH ( 5 %) , Melzer and cotton blue studied by him to possess cyanophobic walls mounts of dried gills· a good proportion of (except in some very occasional spores in T. the spores (especially the immature ones) saponaceum; see later). conspicuously collapsed in water, Melzer and However, in certain species of Tricho cotton blue mounts (at least in mounts of loma (e.g . . T. caligatum, T . inamoenum, dried gills; also in all those cases when T . saponaceum, T. sejunctum, T. sulph deposits were studied) ; spore base invariably ureum) and Collybia (so far only in the obtuse (unless acute in a small proportion species of the Rhodocollybia group: C. of the spores of L. gilua col!.?) ; spore shape maculata, C. distorta and C. butyracea) very ordinary, being ellipsoid or ellipsoid I have observed most curious scattered, oblong, rarely subglobose; suprahilar area of finally sometimes secondarily septate basi the spores very often depressed, if not, then dia, with thick, strongly cyanophilic walls applanated, being smooth under the light throughout, constantly occurring among microscope in rough spore walls also, but normal basidia and producing spores of often (if not always?) centrally slightly ru more or less normal size and shape (ex gose under the electron microscope (BIGELOW cept for those of C. butyracea at a final & RowLEY 1968; PEGLER & YouNG 1971 ) ; stage; see below) but similarly thick-walled spore wall somewhat thickened, inamyloid and strongly cyanophihc. (In add~tion, in and indextrinoid, strongly cyanophilic except C. butyracea narrow belts with the same in very young spores, in which cyanophobic, colour reactions occur around the septa of usually verruculose with obtuse warts often some pileus hyphae.) Certain details of increasing in number and size towards the these basidia are different in different spe spore apex, rarely smooth under the light cies. This phenomenon is, however, not microscope; hilar appendix distinct, rather connected with the cyanophily of the Le small, with cyanophobic (or very weakly pista spore, since these elements occur cyanophilic?) walls; spore contents almost along with the normal ones and are also always with one more or less distinct oil strongly dextrinoid, unlike any cell in Le drop· cystidia of any kind absent; hymeno pista. I have never seen such structures in phoral trama regular or nearly so; cortex Clitocybe, either. of pileus rather poorly differentiated, com This very peculiar situation in Tricho posed of thin filamentous hyphae; all hy loma and Collybia has to my knowledge phae with inamyloid and indextrinoid, prob not been ·reported before in the literature ably also cyanophobic walls; clamp connec not excepting a recent paper on Tricholo tions abundant in all parts of the fruit body; ma (GuLDEN 1969). However, SINGER on bare soil and in litter, often where the ( 1962) does write t

88 found among the normal indextrinoid ones, have cyanophobic walls (according to KuH and in his 1972 paper he reports that a NER 1969 and my own stt_{dies ). In Lepista thin cyanophilic outer layer is present in (and certain Clitocybes) the opposite is true, the wall of a few spores of T. saponaceum. since the spore wall is always cyanophobic However, he fails to observe the conspi in very young spores, its ability to absorb cuous aberrant basidia. It is very interest cotton blue increasing with age. Lastly, clamp ing to note that SINGER & CLEMEN<;:ON connections are commonly absent from these ( 1971 ) have found exactly similar basidia genera with binucleate spores, while they in Aeruginospora hiemalis, calling them never seem to be lacking in Lepista (and »sclerobasidia». only very infrequently in Clitocybe). Unexpectedly, spore characters have The genus Ripartites has clamps and dis been reported as normal in the aphyllo tinctly coloured, uninucleate (KuHNER 1945) phorous genus Jaapia Bres. (see NANN spores possessing verruculose, strongly cyano FELDT & ERIKSSON 1953 : Fig. 1, h-1) that philic walls (KuHNER 1969; BEssoN 1970; are extremely similar to those present in, SINGER 1972 ; my own studies), and, accord e.g., the aberrant spores of C. butyracea, ing to my observations, a small proportion viz. the apparent double structure of the of its spores are adhered together in tetrads wall ( e idently also present in the aberrant in preparations made of dried gills. It is thus basidia in Tricholoma and Collybia), the clearly very close to Lepista taxonomically, occurrence of septa within old detached as has already been pointed out, e.g. by SIN spores and the common collapsing of the GER (1962), KUHNER (1969) and BESSON small basa:l cell, and the response to cotton ( 1970), being to my mind particularly near blue (and also the dextrinoid reaction, to the L. gilva group. As described by SIN according to my own observations on the GER ( 1962) however, Ripartites differs suffi two J a a pia species) . ciently from Lepista to deserve recognition as The phenomenon may be connected an independent genus. I have also found that with a curious type of chlamydospore form in Ripartites the proportion of collapsed spo ation. Another possible explanation is res is smaller than in Le pista. that it is caused by some parasite ( Archi In the comparisons of Lepista with other mycetes?), which has developed in the genera, Clitocybe included, I have not regard basidia and spores of the host species, ed as decisive the two classical features inside the thin, cyanophobic, inamyloid whose combination has hitherto generally and indextrinoid basidial and sporal walls. been supposed to be diagnostic of Lepista, The genera Rhodocybe, Rhodophyllus, i.e. the pinkish spore colour and the verru Clitopilus and their relatives do not appear culose spore wall. This of course results from to be very closely related to Lepista (or Clito my attempts to obtain a more natural delimi cybe). Firstly, they have binucleate spores tation of the genus, in which the amplitude (KuHNER 1945 ), further they usually seem of variation of the spore characters also co to have a thicker spore wall and a deeper vers a deep yellow spore colour and a smooth reddish colour in their spore deposits. The spore wall as seen under the light microscope. two last-mentioned features accord with my The pinkish verruculose spores of Lepista observation that, when viewed under the of course still form an average difference microscope, in water, KOH, or even Mel from, say, Clitocybe. However, my most zer's reagent, even single spores of many of recent observations, to be published on a the species of these genera clearly have red later occasion, show that, besides the well dish-tinted walls, while in Lepista (and Clito known occurrence of pinkish coloured spores cybe) the reddish tinge is hardly observable in in Clitocybe, the genus also contains a few single spores, even if they are pale pinkish species with slightly rough spores ( cf. also in deposit. In addition, in these genera the the spore wall of C. atrostriata Metr.). Mo walls of very young spores attached to the reover, PEGLER and YouNG (1971) report sterigmata are already generally more or less the spore surface of C. clavipes to be strongly cyanophilic, while they may in some rugulose under the electron microscope (this species become less so with age, so that in observation, by the way, confirms my 1969 certain species at least a small proportion opinion that this species deserves a section of the completely mature spores possibly even of its own; it would not be surprising if the

89 spores of the evidently closely related species Mycologicum» (»Code», Art. 33). The »Epi C. avellaneialba Murr. also revealed a slight crisis» is, however, a later work quite differ ly rugose wall when studied under the ent from that starting point publication, nor electron microscope ). C. pseudoirina Big. & is it nomenclaturally considered a part of the Smith (type Smith 71356; MICH) is con »Systema Mycologicum» according to the sidered by BIGELOW & SMITH ( 1969) to »Code» (unlike FRIEs's »Elenchus fungo occupy an intermediate position between rum», 1828) . Thus the abo e tribe of Lepista and Clitocybe as regards its spore FRIES cannot serve as the basionym for new ornamentation (see p. 83 ). The authors claim combinations, from which it follows that ed that its spores were smooth under the the proposed new combination Lepista (Fr. light microscope, even when studied with an 1838) W. G. Smith 1870 is not validly pub oil immersion lens, but, on examining the ty lished, either. However, fortunately this prob pe and only specimen, I can tell that in lem can be solved with practically no altera reality a large proportion are distinctly rough tions to the current taxonomy or nomencla as in the true L. irina, appearing so not on ture of Lepista. Somewhat later (Summa ve ly when stained with cotton blue, but also in getabilium Scandinaviae 2: 306, 1849) FRIES Melzer's reagent, and even at as low a magni treats the Lepista group immediately un fication as x 600. Thus the classical diag der the generic name Paxillus as an infra nostic features of C. pseudoirina (pinkish generic taxon whose rank he fails to indicate: spore colour; at least many of the spores ver »Paxillus a. Lepista». The characters of this ruculose) indicate that it should be placed group »a.» are described in a few words and in Lepista, giving no support to the idea t'hat three species are included: »1. P. Lepista [in it is an intermediate species. This is confirmed italics] I 2. P. extenuatus ( Scop.) I 3. P. by my further studies on the type, which sordarius (Pers.)», none of them being, how showed that a part of the spores occur in ever, designated as the type. This taxon tetrads, that a proportion of them are col without a designation of rank is the first lapsed, and that the spore wall is strongly cya supraspecific taxon, validly published in all nophilic. Moreover, all the characters o.f C. respects, which can be typified with Agaricus pseudoirina, both macroscopic and micro lepista Fr., and, although FRIES of course scopic, strongly suggest that it is conspecific means by it the same group of fungi as in with L. irina. The other species thought by the »Epicrisis» under the same Latin epithet, BIGELOW and SMITH to have an intermediate Paxillus a. Lepista must be treated as a new kind of spore surface, C. highlandensis Hesl. taxon and not as a mere new combination & Smith, lacks clamp connections, and, as because the name was not validly published admitted by these authors, is thus not a parti in the »Epicrisis». It is this taxon »a. Lepista» cularly suitable example to choose in this case. of Paxillus that may validly be given a new The connections of this at least superficially status. To be exact, the complete citation curious species to Rhodocybe, Tricholoma of the name of that taxon should be »Paxillus and the C. harperi group should be checked a. Lepista Fr. ex Fr.», but the first citation by a careful analysis of its spore characters. »Fr.» and the word »ex» are of course not necessary .in routine use. DoNK ( 1962) inter 7. The basionym and typification of Lepista prets the taxon »a.» as section, but that procedure does not seem correct since in the The basionym of the generic name Lepista work considered FRIES used this kind of is practically invariably considered to be letters (a, b, c, etc.) to denote stirpes in »Paxillus tribus L epista Fr.» (FRIES: Epicrisis, those infrequent cases when he made any 1838), subsequently elevated to the generic mention of the rank (e.g. in the first sub status by W. G. SMITH (Clavis Agaricinorum, genus of Agaricus, subg. Amanita). The stirps 1870). The pame of FRIES is, however, not is, however, not an official rank approved validly published as he misplaced the tribe by the »Code», and moreover, FRIES used through treating it as an infrageneric taxon the word »stirps» and those small letters (International Code of Botanical Nomencla rather inconsistently. The word »section» is ture, 1972, Art. 33) . The only exception to even more rarely found in the work, denoting this rule is the treatment of the tribes of even less any distinctly defined taxonomical FRIES as subdivisions of genera in »Systema position. W. G. SMITH is thus to be considered

90 to have made the new combination Lepista features and the colour of its spores, strongly (Fr. 1838 ex Fr. 1849) W. G. Smith 1870. suggests some species in fact belonging to DaNK ( 1962) seems to have been aware Lepista, especially L. subconnexa (Murr. ) of the facts mentioned above, but, apparent Harmaja (or some very closely related spe ly because he failed to present any detailed cies). L. subconnexa has been shown to occur explanations and emphasize the correct form in Norway and Finland, i.e., on both sides of the basionym, they escaped the attention of Sweden (HARMAJA 1970), so it is most of subsequent workers. probable that it also grows in Sweden, where As the epithet of the subdivision of the it may have been collected by FRIES and been genus Paxillus, the taxon Paxillus a. Lepista, in his hands when he was preparing the is »identical with [or derived from] the original description of Agaricus lepista. L. epithet of one of its constituent species, subconnexa may be a collective species, but this species [Paxillus lepista J is the type of at least one specimen collected in southern the name of the subdivision of the genus unless Finland (Etela-Hame pro ., Lammi, Biologi the original author of that name designated cal Station 1968-07-02, Pertti Uotila; H) another type» (»Code», Art. 22 ). Thus the is conspecific with the North American type »selection of a lectotype» for Lepista, accord as it possesses large cespitose fruit bodies and ing to DaNK ( 1962) first made by W. G. was growing on rich bare soil, or mull. SMITH in 1908 in favour of P. lepista, is su perfluous. 8. The formal proposals of two new The identity of Agaricus lepista Fr. (Paxil combinations lus lepista (Fr.) Fr.; the author citation is mostly given incorrectly as P. lepista Fr. Lepista nebularis (Fr.) Harmaja, n. comb. though this species was originally described (Agaricus nebularis Batsch ex Fries, Systema in the »Systema M ycologicum» under the mycologicum . . . 1: 86. 1821.) generic name Agaricus) has been the subject Lepista subalpina (Big. & Smith) Harma of some discussion. To me the original de ja, n. comb. (Clitocybe subalpina Bigelow scription (as well as the later ones of FRIES) & Smith, Brittonia 21: 155. 1969. - Part of this species, with notes on its macroscopic of holotype [ MICHJ studied. )

REFERENCES

BESSON, M . 1970: Ultrastructure de Ia paroi spa structures of Homobasidiomycetes in cotton rique de quelques Agaricales a ornements blue and its importance for taxonomy. cyanophiles non amylo!des. - C. R. Acad. Feddes Repert. 69 : 131 - 14'2. Sci. 271: D: 1508- 1510 + I- II. Ki.iHNER , R . 1945: Nouvelles recherches sur les BIGELow, H. E. and Row LEY, J. R. 1968: Surface di isions nuclo~aires dans. Ia baside et les replicas of the spores of fleshy fungi. - spores des Agaricales. - C. R. Acad. Sci. Mycologia 60 : 869-887. 220: 618- 620. BIGELOW, H. E. & SMITH, A. H. 1969: The status 1969: Contribution a Ia systematique des of Lepista - a new section of Clitocybe. - Orcelles ( Agaricales) . Cette tribu est-elle Brittonia 21: 144-177. artificielle comme le suggerent des particu DoNK, M. A. 1962: The generic names proposed laritl~s de Ia paroi sporique en microscopie for garicaceae. - Beih .. Nova Hedwigia 5 : photonique? - Bull. Soc. Linn. Lyon 38: 1- 320. 247- 251. GuLDEN, G. 1969: Musseronflora. Slekten Tricho LAMOURE, D . et FICHET, M .-L. 1962 : Rhodopaxil loma (Fr. ex Fr.) Kummer sensu Jato. - lus densifolius Favre, espece nouvel·le pour Ia 96 + 4. Oslo, Bergen & Troms0. France.- Bull. Soc. Linn. Lyon 31: 107- HARMAJA, H. 1969: The genus Clitocybe (Agarica 111. les ) in Fennoscandia. - Kars·tenia 10: 5- NANNFELDT, J. A. and ERIKSSON , J. 1953: On the 168. hymenomycetous genus J aapia Bres. and 1970: Type studies on Agaricales described its taxonomical position. - Svensk Bot. as Clitocybe and Omphalina. - Karstenia Tidskr. 47 : 177-189. 11 : 35- 40. PEGLER, D . N. and YouNG, T. W. K. 1971: Basi 1974: Three new taxa of Lepista: L. fasci diospore morphology in the Agaricales. - c.ulata n. sp., L. singeri n. sp. and Lepista Beih. No\'a Hedwigia 35: 1-210 + 1- subgenus Laevispora n. subg. - Karstenia 53. 14: 129-l 32. RozE, E . 1876: Catalogue des Agarioinees obser KoTLABA, F. and PouzAR, Z. 1964: Preliminary vees aux environs de Paris. - Bull. Soc. results on the staining of spores and other Bot. France 23: 108-115.

91 SINGER, R. 1961 : Type studies on Basidiomycetes. ricales and agaricoid Basidiomycetes. - X. - Persoonia 2: 1- 62 . Mycologia 64: 822-829. 1962 : The Agaricales in modern taxono SINGER, R. und CuiMEN<;:ON, H. 1971: Neue Arten my. - 2nd ed.- 915 + 73. Weinheim. von Agaricales. - Schweizerische Zeitschr. 1972: Cyanophilous spore walls in the Aga- Pilzk. 49: 118- 128.