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In my previous post above, I suggested that William Nylander had changed his mind at least once about the diagnostic characters of Lecanora chlarotera, a species he described somewhat differently three times (1872a, 1872b, 1891). I pointed to Nylander’s differing descriptions as an example of what Lucie Kohler, following August-Marie Hue, called the ‘greatest confusion’ of the ‘old lichenologists’ about the Lecanora subfusca-group, to which L. chlaroterabelongs (Hue, 1903; Kohler 1956, p 167). However, after further research, I’ve revised my opinion: it was Hue who was confused about Nylander’s descriptions. In this post, I’ll argue not only that Hue was confused about Nylander, but also that Nylander might have anticipated one important element of the
subfusca-group classification scheme in use today: the placement of epithecial granules either in a defined layer above the tips of the paraphyses, or also descending between them. Adolf Hugo Magnusson (1932) was the first to develop the modern scheme, which was extended and elaborated by Josef Poelt (1952) and Irwin Brodo (1984). And though Kohler was wrong to follow Hue in ascribing utter confusion to ‘old lichenologists’ such as Nylander, she was right to criticise Hue for rejecting the diagnostic value of epithecial granules in the subfusca-group. I also intend for this post to serve as background for future posts investigating in detail how the British concept of
L. chlaroteracame to be, and how it obscured the existence of another subfusca-group lichen, which was there all along: L. hybocarpa auct. br.But that’s for later. For now, let’s turn back to Hue’s confusion about Nylander and epithecial granules. Hue certainly knew that epithecial granules could be seen in some
subfusca-group species: Quote:Often, it [the epithecium] is bare. Sometimes it is full of small granules of a dark yellow, and then the epithecium is called ‘granular’ —
epithecium granulosum. This is an inaccurate expression, since the granules are not attached to the paraphyses, and they are easily dissolved in potassium hydroxide. Rarely, the granules cover the paraphyses along their whole length. (Hue, 1903, pp 32-33, my translation). Yet as we’ve said, and as Kolher noted, Hue thought that the epithecial granules were not reliable characters for species identification. What’s more, he specifically criticised Nylander for relying upon them to separate some
subfusca-group lichens: Quote:In 1867, in Triana and Planchon,
Prodr. Flor. Nov. Granat.Lich. Supplem., p 543, Mr Nylander attributed to this chlarona-variety [of L. subfuscaAch.] — which he later made a species in its own right — the following diagnostic characters: a whitish, thin, almost smooth or slightly rough thallus; a finely crenulated margin to the apothecia; a granular epithecium and a hymenial gel turning blue in iodine, with the asci taking a violet or reddish-violet tint. Then, in 1872, in his Observ. lichenol. Pyren.-Orient.in Florap. 550 — published in a volume the following year — he [Nylander] separated L. chlaroteraNyl. from [ L. subfusca var.] chlaronaas a new species, distinguishing it from the latter by the more crenulated margin of the apothecia, the non-granular epithecium, the hymenial gel coloured intensely blue by iodine, and the longer spermatia. At first glance, none of these characters could suffice for describing a new species. A few crenulations more or less indicates nothing; the colour of the hymenial gel, i.e.the paraphyses, is the same in both; and lastly, it is not specified how much longer the spermatia are. The only distinctive character that remains, then, is the epithecium, granular or not. But we will see that there are very regularly furrowed apothecia with a granular epithecium, and very little furrowed apothecia with a non-granular epithecium. … What’s more, apothecia with a granular and a non-granular epithecium can be found in the same individual. Consequently, this character, which Mr Nylander regarded as primary, is inconstant, and only one and the same variety exists [ viz. L. subfusca var. chlarona]. (Hue, 1903, p 74, my translation). But Hue was in error. Nylander did not in fact distinguish between a granular epithecium for
L. subfusca var. chlaronaand a non-granular epithecium for L. chlarotera. Nylander distinguished between them in a rather more subtle way: by the placement of granules between the tips of the paraphyses, or only atop them. Hue, who did not think epithecial granules important, failed to grasp Nylander’s meaning. Remarkably, in according such importance to both the presence and the placement of epithecial granules, Nylander was anticipating today’s Magnusson/Poelt/Brodo scheme. For this reason alone, it’s worth examining in detail what Nylander actually wrote, beginning with the description of
L. subfusca var. chlaronathat Hue cites: Quote:Var.
chlarona(Ach., Lich. U., p 397; Nyl., l. c.[ Lich. Scandinav.], p. 160).—Thallus white, thin, sublaevigate or subrugose, determinate; apothecia pale flesh colour or pale dull red (0.5-0.9 mm diam.), with a crenulated thalline margin, constricted; spores 9-15 µm long, 5-8 µm wide; paraphyses slender, inspersed at the tips (at the epithecium) with yellowish granules. (Nylander, 1867, p 543, my translation). Note that Nylander carefully distinguishes between the paraphyses and the epithecium: he uses the latter term to refer only to the surface of the apothecium, i.e. the surface formed by the tips of the paraphyses. Moreover, Nylander says that it’s the paraphyses themselves that are inspersed with granules, albiet at their tips: ‘
paraphyses graciles apice (epithecio) granulis lutescentibus inspersae’. In fact, this translation of the Latin is conservative: another valid translation is ‘paraphyses slender at the tips (at the epithecium), inspersed with yellowish granules’. But Hue failed either to notice this distinction, or to consider it significant, saying only that Nylander described the chlarona-variety as having a ‘granular epithecium [ épithécium granulé]’. Further evidence that Nylander intended a more subtle distinction between granular epithecium and granular paraphyses comes from his descriptions of
L. chlarotera, which as Hue noted he distinguished from the chlarona-variety. According to Hue, Nylander wrote that the epithecium of L. chlaroterawas non-granular, citing his December 1872 description in the journal Flora. But Hue was incorrect here, and perhaps he was even being a bit disingenuous. He knew that Nylander had described L. chlaroterathree times, having cited all three descriptions in his 1903 paper, and what’s more he knew that: [list]- Nylander had published his protologue for
L. chlaroterain January 1872 in the journal Bullétin de la Société de Normandie, in which he said that the paraphyses, not the epithecium, lacked granules (‘ paraphyses non inspersae’) (1872a, p 274); [/list] [list]- Nylander had offered no information about granules whatsoever in his December 1872 description of
L. chlaroterain the journal Flora(1872b, p 550), the one Hue cited to support his criticisms of Nylander; [/list] [list]- Nylander had asserted that
L. chlaroterahad a granular epithecium (‘ epithecium inspersum’) in his third and last re-description (1891, p 44), while explicitly describing other species in the same publication as having granular paraphyses (e.g. L. chlarodes, of which Nylander wrote ‘paraphyses tapering upwards, finely inspersed [ paraphyses gracilescentes sursum subtiliter inspersae]’). [/list] The only way to make consistent sense of these three descriptions is to understand Nylander to mean that the two lichens differ not in having epithecial granules — since they both do — but in the placement of the granules. Unlike in the
chlarona-variety, the paraphyses of L. chlaroteraare not inspersed with granules (‘ paraphyses non inspersae’), yet its epithecium is still formed of a layer of granules atop the paraphyses (‘ epithecium inspersum’). But doesn’t this conclusion amount to absolving Nylander of an error while simultaneously attributing one to Hue? Even so, they cannot both be correct, especially considering that Hue claimed to have examined two specimens that Nylander determined as
L. chlarotera— including one from the Canary Islands to which Nylander explicitly referred in his 1891 description of L. chlaroterawith epithecium inspersum— and found them both to lack any granules (Hue, 1903, p 77-78)! Ultimately, the balance of evidence appears to me to favour Nylander over Hue — not only the evidence above, but also the following evidence:
[list]- Nylander’s own herbarium specimen for
L. chlarotera— collected in Germany near Jena in 1797 by Christian von Steven — has granules only atop the paraphyses (‘ epithecium inspersum’) and not between them (‘ paraphyses non inspersae’). See Figures 1 and 2 below for photographs of the specimen, now held at the University of Helsinki as H-NYL 27437 and considered to be the L. chlaroteralectotype. Note especially the pencil sketch at the top left of Figure 2, labelled ‘ Epithecium inspersum’ and showing clearly that the granules form a layer atop the paraphyses only. [/list] - Nylander’s distinction between the epithecium, in the sense of the very surface of the apothecium, and what’s sometimes called the epihymenium, in the sense of the topmost part of the hymenium that also includes the epithecium, is often elided in lichenology. The term ‘epithecium’ is often used to mean the epihymenium, and it’s not hard to imagine that Hue, who didn’t consider epitheical granules or their placement diagnostically important, might use the term in that way for simplicity’s sake.
[list][/list] - The
chlarona-variety of L. subfuscahas since been circumscribed as L. pulicaris, the classic subfusca-group species with granules between the paraphyses (Brodo, 1984; Brodo & Vitikainen, 1984).
[list][/list] I’d like to add yet a further piece of evidence, which would conclusively decide the case: an examination of the Canary Islands
L. chlaroteraspecimen, which Nylander described as having an epithecium inspersum, and Hue described as having an épithécium non granulé. The specimen was collected in 1845 or 1846 by Eugène Bourgeaux on behalf of Philip Barker Webb (Nylander, 1891; Raymond, 1972). I believe it can be found today in the Webb collection in the Herbarium Centrale Italicum in Florence, but I don’t have any access to it. Be that as it may, Hue’s own
subfusca-group classification scheme, which prioritised external morphological characters such as the shape of the thalline margin, was superseded by the Magnusson/Poelt/Brodo scheme that I argue Nylander anticipated in a small way. For more, see my previous post above. And as I discussed in that post, Neil Sanderson’s 2019 discovery of
L. hybocarpa auct. br.suggests that the Magnusson/Poelt/Brodo scheme might require further revision, at least for the British Isles. In future posts, I’ll turn back to that point, trying to shed some light on it by investigating how the British concept of
L. chlaroteracame to be. REFERENCESBrodo IM (1984).The North American species of the Lecanora subfuscagroup. Beihefte zur Nova Hedwigia79: 63–185. Brodo IM & Vitikainen O (1984).The typification of Lecanora subfusca(L.) Ach., its varieties and some of its related taxa published before 1850. Mycotaxon21: 281-298. https://www.researchgate.net/publication/285029816_The_typification_of_Lecanora_subfusca_L_Ach_its_varieties_and_some_of_its_related_taxa_published_before_1850. ” class=”bbcode_url”> https://www.researchgate.net/publication/285029816_The_typification_of_Lecanora_subfusca_L_Ach_its_varieties_and_some_of_its_related_taxa_published_before_1850. Hue A-M (1903).Causerie sur le Lecanora subfuscaAch. Bulletin de la Société Botanique de France50: 22-86. https://www.biodiversitylibrary.org/item/272970https://www.biodiversitylibrary.org/item/272970” class=”bbcode_url”> Kohler L (1956).Remarques sur les Lecanoracorticoles du group subfusca: Leur répartition dans les Alpes du Dauphiné. Revue bryologique et lichenologique25: 167-182. https://www.biodiversitylibrary.org/bibliography/169357https://www.biodiversitylibrary.org/bibliography/169357” class=”bbcode_url”> Magnusson AH (1932).Beiträge zur Systematik der Flechtengruppe Lecanora subfusca. Meddelanden Från Göteborgs Botaniska Trädgård7: 65–87. Nylander W (1867).Lichenes. In J Triana & JE Planchon, Prodromus Florae Novo-Granatensis: Cryptogamie. https://bibdigital.rjb.csic.es/records/item/9742-prodromus-florae-novo-granatensis-cryptogamie ” class=”bbcode_url”> https://bibdigital.rjb.csic.es/records/item/9742-prodromus-florae-novo-granatensis-cryptogamie Nylander W (1872a).Observata lichenologica in Pyrenæis Orientalibus. Bulletin de Société Linnéene de Normandie2(6): 256-328 https://www.biodiversitylibrary.org/item/37520https://www.biodiversitylibrary.org/item/37520” class=”bbcode_url”> Nylander W (1872b).Observata lichenologica in Pyrenæis Orientalibus. Flora55: 424-431 & 546-554. https://www.biodiversitylibrary.org/item/971https://www.biodiversitylibrary.org/item/971” class=”bbcode_url”> Nylander W (1891).Lichenes Pyrenæorum Orientalium: Observatis Novis. https://catalog.hathitrust.org/Record/100653227https://catalog.hathitrust.org/Record/100653227” class=”bbcode_url”> Poelt J (1952).Die Lecanora subfusca-gruppe in Süddeutschland. Berichte der Bayerischen Botanischen Gesellschaft29: 58–69. https://www.bbgev.de/_files/ugd/f05de5_d67aa0972cb04a418c12edec88586a2f.pdf ” class=”bbcode_url”> https://www.bbgev.de/_files/ugd/f05de5_d67aa0972cb04a418c12edec88586a2f.pdf Raymond M (1972).Bourgeaux, Eugène. In Dictionary of Canadian Biography, vol 10. http://www.biographi.ca/en/bio/bourgeaux_eugene_10E.html ” class=”bbcode_url”> http://www.biographi.ca/en/bio/bourgeaux_eugene_10E.html 
[attachment=1]H-NYL 27347 Lecanora chlarotera lectotype 1.png[/attachment] 
[attachment=0]H-NYL 27347 Lecanora chlarotera lectotype 2.png[/attachment] Following up further on the K+ brown reaction for fumarprotocetraric acid that Neil mentioned in this thread. In search of a more convincing result, I applied K to another spot on my specimen of Cladonia furcataabove. Rewarded with a clear K+ brown reaction, I applied Pd directly nearby. The strong Pd+ red demonstrates the presence of fumarprotocetraric acid, as expected. And the lack of any K/UV+ yellow flurorescence on the K-spot suggests fairly unmistakeably that the K+ brown is due to fumarprotocetraric acid, and not by strange chance to any trace of atranorin, which C. furcatacan sometimes contain. 
[attachment=3]20240204-P2040014.jpg[/attachment] 
[attachment=2]20240204-P2040016.jpg[/attachment] 
[attachment=1]20240204-P2040017.jpg[/attachment] An interesting note: where Pd overlapped K, the brown reaction became yellow. I wonder what Pd+ yellow compound results from the decomposition of fumarprotocetraric acid in K?
Another interesting note: a Google search on the K+ brown reaction for fumarprotocetraric acid turned up this 1935 article by American lichenologist RH Torrey entitled ‘Paraphenylenediamine: A new colour test for lichens’:
https://www.jstor.org/stable/40597010https://www.jstor.org/stable/40597010” class=”bbcode_url”> It appears from Torrey’s article that, until Pd came along, some lichenologists relied on the K+ brown reaction for fumarprotocetraric acid to help separate
Cladoniaspecies. Neil noted above that the reaction is still mentioned in North American Cladonialiterature. And the table of colour reactions in IM Brodo’s 2001 North American flora lists fumarprotocetraric acid as ‘K+ brownish’. 
[attachment=0]Screenshot 2024-02-08 at 22.43.30.png[/attachment] Torrey suggests that the K+ brown reaction is also detailed in what he calls Annie Lorrain Smith’s ‘Manual of British Lichens’. That’s not a title of Smith’s of which I’m aware. So far as I know, Smith published a field guide entitled
A Handbook of the British Lichens(1921), a flora in two volumes entitled A Monograph of the British Lichens(1911 and 1918), and a treatise entitled simply Lichens(1921). In none of those works by Smith could I find any reference to K+ brown for fumarprotocetraric acid. She mentions only K+ yellow for atranorin in her descriptions of
Cladoniaspecies (unless I’m missing something). I also couldn’t find it in the 1913 beginner’s flora by Gustav Lindau that Torrey calls ‘Die Flechten für Anfänger’, though the electronic copy I found online was hard to navigate. (Apparently, the proper title is Kryptogammenflora für Anfänger, Band 3: Die Flechten.) That isn’t to say the K+ brown reaction isn’t found in any British work: it’s mentioned in in Orange, Smith & James’s 2010 monograph
Microchemical Methods(p 12), for example. I also found it mentioned alongside Pd+ red as a diagnostic for Usnea antarcticain this 1964 flora of Antarctic lichens published by the British Antarctic Survey: https://core.ac.uk/download/pdf/33451352.pdfhttps://core.ac.uk/download/pdf/33451352.pdf” class=”bbcode_url”> U. antarcticain some online descriptions from Australia and New Zealand that I found in my Google search.) But anyway: assuming that there isn’t a ‘Manual of British Lichens’ by Annie Lorrain Smith of which I’m unaware, the K+ brown reaction for fumarprotocetraric acid on which Torrey and other (presumably mainly North American) lichenologists relied doesn’t seem to have been much used by British lichenologists before being obviated by the more effective Pd+ red.
Neil Sanderson wrote:
GerraultHow yellow is the reaction? I looks quite brownish to me. Potentially the K+ brownish reaction to fumarprotocetraric acid; this is often weak and is clearest when there is a lot of fumarprotocetraric acid in the lichen. As it is inconsistent it tends not to be mentioned in descriptions, although American
Cladonialiterature does mention it more. We should have added a note on this reaction in the Cladoniaceae volume of the LBGI, but I forgot. Neil
Apropos of Neil’s comment above about a K+ brownish reaction to fumarprotocetraric acid, I believe I may have observed it on a
Cladonia furcataspecimen that I collected this summer in Scotland (VC101 Kintyre : NR77 Ormsary : August 2023 : In pocket of humus on siliceous rock). The first photo below shows a Pd-test with a strong red reaction as expected. The second shows a K-test presumably with Neil’s weak brown reaction. Many thanks to Mark for pointing out to me the connection to the discussion in this thread. 
[attachment=1]20240121-P1211315.jpg[/attachment] - Nylander had published his protologue for
