Thamnolic Acid Research Articles

Visualizing usnic acid with anisaldehyde reagent

AbstractThe pale yellowish tint of usnic acid in a lichen thallus itself is a commonly used character in identification keys, particularly in the genus Cladonia. Furthermore, the presence of usnic acid is phylogenetically significant in numerous groups of lichens. While the distinctive colour of usnic acid is readily visible when present in high concentrations, it is commonly problematic to discern when in low to moderate concentrations. We explored the use of an anisaldehyde reagent for visualizing usnic acid. Using both usnic acid-containing Cladonia samples and pure usnic acid, this reaction quickly yields a bright magenta colour on HPTLC and TLC plates after heating and directly with crude acetone extracts on glass slides heated with a lighter. The same magenta product was observed whether or not the usnic acid was accompanied by barbatic, fumarprotocetraric, psoromic, squamatic or thamnolic acids, each of which alone did not produce any colour with anisaldehyde reagent. However, the merochlorophaeic acids in C. albonigra also produced a red reaction. Analysis by high resolution LC-MS of the reaction mixture between anisaldehyde and usnic acid revealed several ions at m/z 477.1586 ([M+H]+, C27H25O8) and 463.1385 ([M+H]+, C26H23O8), respectively, consistent with aldol condensation of usnic acid and p-anisaldehyde.

Phylogeny of the genus Loxospora s.l. (Sarrameanales, Lecanoromycetes, Ascomycota), with Chicitaea gen. nov. and five new combinations in Chicitaea and Loxospora.

Loxospora is a genus of crustose lichens containing 13 accepted species that can be separated into two groups, based on differences in secondary chemistry that correlate with differences in characters of the sexual reproductive structures (asci and ascospores). Molecular phylogenetic analyses recovered these groups as monophyletic and support their recognition as distinct genera that differ in phenotypic characters. Species containing 2'-O-methylperlatolic acid are transferred to the new genus, Chicitaea Guzow-Krzem., Kukwa & Lendemer and four new combinations are proposed: C.assateaguensis (Lendemer) Guzow-Krzem., Kukwa & Lendemer, C.confusa (Lendemer) Guzow-Krzem., Kukwa & Lendemer, C.cristinae (Guzow-Krzem., Łubek, Kubiak & Kukwa) Guzow-Krzem., Kukwa & Lendemer and C.lecanoriformis (Lumbsch, A.W. Archer & Elix) Guzow-Krzem., Kukwa & Lendemer. The remaining species produce thamnolic acid and represent Loxospora s.str. Haplotype analyses recovered sequences of L.elatina in two distinct groups, one corresponding to L.elatina s.str. and one to Pertusariachloropolia, the latter being resurrected from synonymy of L.elatina and, thus, requiring the combination, L.chloropolia (Erichsen) Ptach-Styn, Guzow-Krzem., Tønsberg & Kukwa. Sequences of L.ochrophaea were found to be intermixed within the otherwise monophyletic L.elatina s.str. These two taxa, which differ in contrasting reproductive mode and overall geographic distributions, are maintained as distinct, pending further studies with additional molecular loci. Lectotypes are selected for Lecanoraelatina, Pertusariachloropolia and P.chloropoliaf.cana. The latter is a synonym of Loxosporachloropolia. New primers for the amplification of mtSSU are also presented.

Three new species of siphuloid lichens, with a first key to the genus Parasiphula

AbstractThe term ‘siphuloid’ is introduced for a suite of distinct lichen genera with a superficially similar foliose to fruticose morphology, notably Siphula, Siphulella, Siphulopsis, Parasiphula and Knightiellastrum. Three new species are described: Parasiphula squamosa Kantvilas (from Tasmania and New Zealand), characterized by a whitish grey, squamulose or minutely foliose thallus lacking lichen substances or containing traces of atranorin; Siphula capensis Kantvilas (from southern Africa), containing baeomycesic and squamatic acids, and characterized by robust, broadly flattened, rounded lobes with thickened apices; and S. crittendenii (from the Caribbean but with an outlying collection from Queensland, Australia), an epiphytic species containing thamnolic acid, with fragile, flattened lobes mostly to 10 mm long and 1−5 mm wide, with ragged or much-divided apices. Salient features of the species of Parasiphula are summarized and a first key for this genus is presented. Infrageneric problems in Siphula are also discussed briefly.

Effect of several phenolic compounds of lichens on the physiological, cytological, and biochemical characteristics of Allium fistulosum seedlings

Abstract Here we report the effects of atranorin (ATR), gyrophoric acid (GPA), and thamnolic acid (TMA) on the physiological, biochemical, and cytological characteristics of Allium fistulosum L. seedlings for the first time. Of the lichen substances investigated, ATR and TAM had the highest phytotoxicity effects. ATR (4000 - 1000 μM) and TAM (4000 μM) inhibited the growth processes and increased the intensity of lipid peroxidation in A. fistulosum, and as a result the activities of the protective enzymes peroxidase, catalase, and superoxide dismutase increased, and the contents of photosynthetic pigments in the A. fistulosum seedlings decreased. ATR at concentrations 2000 and 4000 μM caused decrease of mitotic activity and increase of chromosomal aberrations frequency in root cells. The weakest phytotoxic properties were shown by GPA, which caused no changes in the physiological, cytological, or biochemical parameters of the A. fistulosum seedlings across the entire range of concentrations tested.

Naming and describing the diversity in the Usnea cornuta aggregate (lichenized Ascomycota, Parmeliaceae) focusing on Brazilian specimens

This study is a reassessment of the Usnea cornuta aggregate diversity mainly in Brazil. Based on previous multi-locus species delimitation analyses using the multispecies coalescent model (MSC), we carried out a posteriori morphological and anatomical studies. The following corticolous new species are described: Usnea arianae with norstictic or fatty or lobaric acids, convex and efflorescent soralia and a lax medulla; U. flabelliformis with protocetraric acid, fan-shaped main branches and a high medulla/cortex ratio; U. rubropallens with protocetraric acid and a faint orange cortical/subcortical pigment; U. stipitata with constictic acid, stipitate soralia and a high medulla/cortex ratio; and U. tenuicorticata with protocetraric acid, a thin cortex and a high medulla/cortex ratio. The newly described species were found to occur so far only in the Americas, except U. arianae which shows an amphi-atlantic distribution in Europe and on the American continent. Seven species already described belonging to the U. cornuta aggr. in Brazil are further treated here: Usnea boomiana with caperatic acid and large, concave soralia, new to South America; U. brasiliensis with protocetraric acid, minute and irregular soralia; U. cornuta with mainly salazinic acid and minute soralia fusing into consoralia; U. macaronesica (syn. nov.: U. subglabrata) with barbatic acid, large excavate soralia and a lax medulla; Usnea subpectinata, a so far european species resurrected from the U. cornuta synonymy, with stictic acid and numerous isidiofibrils, new to South America; and U. trachyclada with thamnolic acid and K+ bright yellow stipitate soralia. Full descriptions with morphological, anatomical and chemical features, geographical distributions, and illustrations are provided for each species along with an identification key.

A molecular-genetic reassessment of the circumscription of the lichen genusIcmadophila

AbstractThe circumscription of the lichenized ascomycete genusIcmadophilaTrevis. in the familyIcmadophilaceaeTriebel was investigated. Sequences of the internal transcribed spacer (ITS) region and large subunit of nuclear ribosomal DNA (nuLSU) were generated for the fiveIcmadophilaspecies and additional members ofIcmadophilaceaefrom the generaDibaeis,Endocena,Knightiella,Siphula,SiphulellaandThamnolia. Phylogenetic analyses indicate that threeIcmadophilaspecies are closely related: the type,I. ericetorum(L.) Zahlbr., which is widespread in Eurasia and North America,I. aversa(Nyl.) Rambold & Hertel from Central and South America, andI. japonica(Zahlbr.) Rambold & Hertel, which is restricted to Far East Russia and Japan. The genusKnightiellaMüll. Arg. is reinstated to accommodateI. splachnirima(Hook.f. & Taylor) D. J. Galloway emend. L. Ludw., which occurs in New Zealand and Australia. Two further species ofKnightiella,K. eucalypti(Kantvilas) Kantvilas andK. queenslandicaKantvilas, are found to be unrelated toK. splachnirima, and are accommodated in two newly described genera,KnightiellastrumandSiphulopsisrespectively.KnightiellastrumL. Ludw. & Kantvilas is characterized by a squamulose, erhizinate, whitish to pale grey thallus with a green, coccoid photobiont and by containing thamnolic acid.SiphulopsisKantvilas & A. R. Nilsen is similarly characterized by an erhizinate, whitish to pale grey thallus, with a green, coccoid photobiont and containing thamnolic acid, but is instead fruticose. This study reveals considerable diversity within AustralasianIcmadophilaceae; ongoing work in the Southern Hemisphere and tropical regions may reveal additional species in this family and clarify the relationships of these newly described genera.

Xylopsora canopeorum (Umbilicariaceae), a new lichen species from the canopy of Sequoia sempervirens.

Xylopsora canopeorum Timdal, Reese Næsborg & Bendiksby is described as a new species occupying the crowns of large Sequoia sempervirens trees in California, USA. The new species is supported by morphology, anatomy, secondary chemistry and DNA sequence data. While similar in external appearance to X. friesii, it is distinguished by forming smaller, partly coralloid squamules, by the occurrence of soralia and, in some specimens, by the presence of thamnolic acid in addition to friesiic acid in the thallus. Molecular phylogenetic results are based on nuclear (ITS and LSU) as well as mitochondrial (SSU) ribosomal DNA sequence alignments. Phylogenetic hypotheses obtained using Bayesian Inference, Maximum Likelihood and Maximum Parsimony all support X. canopeorum as a distinct evolutionary lineage belonging to the X. caradocensis–X. friesii clade.

Thamnolia tundrae sp. nov., a cryptic species and putative glacial relict

AbstractThe lichen species of the genus Thamnolia, with their striking wormlike thalli and frequent occurrence in arctic and tundra environments, have often been debated with regard to the use of chemistry in lichen taxonomy. Phylogenetic studies have arrived at different conclusions as to the recognition of species in the genus, but in a recent study based on the analyses of six nuclear markers (genes or noncoding regions) of a worldwide sample of Thamnolia, we showed the existence of three well-supported lineages with two different chemistries and geographical distributions. Here, we present two analyses based on ITS and three markers, respectively, which were extended from the study mentioned above to include type specimens and additional Thamnolia strains and taxa. In these analyses the same three clades were retrieved. A putative DEAD-box helicase is used here for the first time as an informative phylogenetic marker to provide taxonomic resolution at species level. The distribution of morphological and chemical characters across the phylogeny was analyzed and it was concluded that three morphologically cryptic, but genetically well supported, species occur: T. vermicularis s. str., T. subuliformis s. str. and T. tundrae sp. nov. Thamnolia vermicularis s. str. contains individuals with uniform secondary chemistry (producing thamnolic acid) and a rather limited distribution in the European Alps, Tatra Mts and the Western Carpathians, a distribution which might result from glacial survival in an adjacent refugium/refugia. Thamnolia subuliformis s. str. is widely distributed in all hemispheres and the samples contain two chemotypes (either with thamnolic or squamatic acids). Thamnolia tundrae is described as new; it produces baeomycesic and squamatic acids, and has a distribution limited to the arctic tundra of Eurasia extending to the Aleutian Islands in North America. It may have survived the latest glaciation in coastal refugia near its present distribution. Thus, secondary chemistry alone is not suitable for characterizing species in Thamnolia, secondary chemistry and geographical origin are informative, and the ITS region can be confidently used for species recognition. Nomenclatural notes are given on several other names that have been used in Thamnolia.

Lichen secondary metabolites affect growth of Physcomitrella patens by allelopathy.

Lichen secondary metabolites can function as allelochemicals and affect the development and growth of neighboring bryophytes, fungi, vascular plants, microorganisms, and even other lichens. Lichen overgrowth on bryophytes is frequently observed in nature even though mosses grow faster than lichens, but there is still little information on the interactions between lichens and bryophytes.In the present study, we used extracts from six lichen thalli containing secondary metabolites like usnic acid, protocetraric acid, atranorin, lecanoric acid, nortistic acid, and thamnolic acid. To observe the influence of these metabolites on bryophytes, the moss Physcomitrella patens was cultivated for 5weeks under laboratory conditions and treated with lichen extracts. Toxicity of natural mixtures of secondary metabolites was tested at three selected doses (0.001, 0.01, and 0.1%). When the mixture contained substantial amounts of usnic acid, we observed growth inhibition of protonemata and reduced development of gametophores. Significant differences in cell lengths and widths were also noticed. Furthermore, usnic acid had a strong effect on cell division in protonemata suggesting a strong impact on the early stages of bryophyte development by allelochemicals contained in the lichen secondary metabolites.Biological activities of lichen secondary metabolites were confirmed in several studies such as antiviral, antibacterial, antitumor, antiherbivore, antioxidant, antipyretic, and analgetic action or photoprotection. This work aimed to expand the knowledge on allelopathic effects on bryophyte growth.

Lichen biodiversity: A source of secondary metabolites active against Candida biofilms

The frequency of infections involving fungal biofilms (in particular associated with Candida yeasts) as well as their resistance to current treatments, justified the need to discover new anti-biofilm substances [1]. Lichens correspond to a symbiotic association between an alga and/or a cyanobacteria and a fungus and are a reservoir for novel compounds with therapeutic potential. For these reasons, this research program was focused on the access to original compounds from lichens from the French Limousin region [2]. A screening of forty lichen extracts was performed against planktonic Candida albicans by evaluating MICs. Moreover, the activity of these extracts was studied against the development (up to 48h) of C. albicans biofilms on polystyrene substrates, using the XTT method. These studies showed that none of extracts active against planktonic C. albicans (MIC> 0.1 mg/mL). However, eleven extracts demonstrated a significant anti-biofilm activity (p < 0.05) for concentrations less than 50 µg/mL. Among them, the Cladonia parasitica extract (43 µg/mL at 24h) was selected for further investigation. HPLC analysis showed poor chemical diversity of the extract which contained 72% thamnolic acid. This depside was active against Candida biofilms at 14.5 and 33 µg/mL at 24 and 48h respectively. Among the most active extracts, Evernia prunastri, Ramalina fraxinea, R. fastigiata, Xanthoparmelia conspersa and Peltigera hymenina displayed significant anti-biofilm activity (p < 0.05) for concentrations less than 10 µg/mL; in particular for E. prunastri and R. fastigiata whose activity was observed as soon as 24h and persisted at 48h. This work demonstrated the anti-biofilm activity of lichens from local biodiversity and thamnolic acid against C. albicans and highlighted the potential of lichens to fight Candida biofilms.

Uncommon Chlorinated Xanthone and Other Antibacterial Compounds from the Lichen Cladonia incrassata

Bioassay-guided fractionation of an extract of the lichen Cladonia incrassata against Staphylococcus aureus led to a novel compound, 1,5-dihydroxy-2,4,6-trichloro-7-methylxanthone (1), along with six known compounds: (-)-usnic acid (2), didymic acid (3), condidymic acid (4), squamatic acid (5), thamnolic acid (6), and prasinic acid (7). Didymic, condidymic, and prasinic acids were isolated for the first time from C. incrassata. Didymic, condidymic, and (-)-usnic acids were active against S. aureus (a minimum inhibitory concentration of 7.5 µg/mL).

Characterisation of phenols and antioxidant and hypolipidaemic activities of Lethariella cladonioides

This study aimed to investigate the antioxidant and hypolipidaemic activities of an ethanol extract of Lethariella cladonioides (Nyl.) Krog (EE) and to characterise its chemical constituents. Nine phenols were identified as canarione, thamnolic acid, squamatic acid, vermicularin, norstictic acid, baeomycesis acid, lecanoric acid, barbatinic acid and usnic acid from analysis of EE by using high-performance liquid chromatography with a diode array detector-mass spectrometry. In antioxidant analysis in vitro, the highest scavenging rate of EEs on the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, superoxide anion, hydroxyl radicals and hydrogen peroxide was 81.55 ± 1.95%, 81.84 ± 4.00%, 74.28 ± 3.71% and 74.28 ± 3.71%, respectively. Meanwhile, after administration of EE for 6 weeks in high fat/cholesterol diet mice, the most significant reduction in levels of serum triglyceride, serum total cholesterol, serum low density lipoprotein cholesterol and liver malondialdehyde were 24%, 20%, 15% and 35%, respectively. The most significant increase in levels of serum high density lipoprotein cholesterol and liver superoxide dismutase was 35% and 88%, respectively. L. cladonioides possesses strong antioxidant and hypolipidaemic activities.

Three New Phenolic Compounds from the LichenThamnolia vermicularisand Their Antiproliferative Effects in Prostate Cancer Cells

Three new phenolic compounds, thamnoliadepsides A (1), B (2), and thamnolic acid A (3), and seven known compounds, everninic acid (4), baeomycesic acid (5), β-orcinol (6), β-resorcylic acid (7), ethyl orsellinate (8), squamatic acid (9), and vermicularin (10), were isolated from the lichen Thamnolia vermicularis (Sw.) Ach. ex Schaerer. Their structures were determined based on spectroscopic analysis, including 2D-NMR experiments and HR-MS techniques. Compound 1 inhibited growth of prostate cancer cells and bonded to G-quadruplex DNA based on NMR determination.

A new Lepraria from Brazil

Lepraria brasiliensis is described from Minas Gerais, Brazil. It is mainly characterized by the presence of thamnolic acid and atranorin as chemical constituents.

High acidity tolerance in lichens with fumarprotocetraric, perlatolic or thamnolic acids is correlated with low pK a1 values of these lichen substances

The depsidone fumarprotocetraric acid as well as the depsides perlatolic and thamnolic acids are lichen secondary metabolites. Their first dissociation constants (pK a1) in methanol were determined to be 2.7 for perlatolic acid and 2.8 for fumarprotocetraric and thamnolic acids by UV spectroscopy. Lower pK a1 values are, so far, not known from lichen substances. Several lichens producing at least one of these compounds are known for their outstanding tolerance to acidic air pollution. This is demonstrated by evaluating published pH preferences for central European lichens. The low pK a1 values suggest that strong dissociation of the studied lichen substances is a prerequisite for the occurrence of lichens with these compounds on very acidic substrata, as protonated lichen substances of different chemical groups, but not their conjugated bases, are known to shuttle protons into the cytoplasm and thereby apparently damage lichens.

Calicium sequoiae, a new lichen species from north-western California, USA

Abstract:We describe Calicium sequoiae as a new species of lichenized Ascomycota from north-western California, USA. The species is distinguished morphologically from other known members of Calicium by its stalks that react I+ blue, mature ascospores that are ornamented with spiral ridges, and apothecia that produce prominent white pruina. It is also the only Calicium known to produce thamnolic acid as a major secondary substance. Sequences from the ITS-region showed C. sequoiae to be unique among calicioid Physciaceae, and phylogenetic analysis positioned it close to C. adspersum, C. chlorosporum, C. lenticulare, Cyphelium notarisii, and C. tigillare. Thus far, Calicium sequoiae has been collected only from old-growth redwood (Sequoia sempervirens) forests, where it occurred on thick, fibrous bark of large redwood trees. A key to the 12 species of Calicium known from the Pacific Northwest is provided.

Antimicrobial activity of some lichen substances

Lichen substances comprise quite different classes of compounds like aliphatic acids, amino acid derivatives, polyols, lactones, quinones, depsides, depsidones, depsones, dibenzofuranes, chromones, terpenoids, steroids and carotenoids [1]. In general, lichens produce some characteristic metabolites, which have yet to be found in higher plants [1]. The secondary metabolites possess a broad spectrum of biological activities including antibiotic, antiviral, anti-inflammatory, antiproliferative, analgesic and cytotoxic effects [1]. For example, usnic acid has antitumour, antimutagenic, analgesic, antipyretic and enzyme inhibitory activity. In the present study, some Caloplaca, Evernia, Thamnolia, Usnea and Cetraria lichens growing in Serbia and Laurera benguelensis collected in Thailand were examined. Until now, there are no reports of phytochemical and antimicrobial studies for L. benguelensis. Metabolites from methanolic extracts were separated on a silica gel column using benzene-acetone mixtures as eluents. Usnic acid, evernic acid, protolichesterinic acid, thamnolic acid, squamatic acid, some naphthaquinones and anthraquinones 1–7 were isolated and identified. Extracts and compounds were tested against 12 bacterial and 12 fungal strains.

Recent literature on lichens—203

Adler, M., S. Calvelo & J. A. Elix. 2006. The distinction between Menegazzia cincinnata and M. valdiviensis (Parmeliaceae). Mycotaxon 95: 217–228. [Separation of two taxa from southern South America best done using ascospore length and presence or absence of thamnolic acid in the medulla.] Amtoft, A. 2006. A new species of Dermatocarpon (Verrucariaceae) from the United States and the Bahamas. The Bryologist 109(2): 182–184. [New: Dermatocarpon tomentulosum sp. nov. (Bahamas, Texas, Missouri).] Archer, A. W. & J. A. Elix. 2005 [2006]. A new species of Pertusaria from Western Australia. Mycotaxon 94: 133–135. [New: Pertusaria subarida sp. nov., corticolous on Melaleuca and Acacia with small ascospores and producing of planaic acid and 4,5-dichlorolichexanthone as major secondary metabolites. This issue was not distributed until May, 2006.] Bartok, K., A. Guttova & L. Lokos. 2005. Contributions to the epiphytic lichen flora of Poiana Rusca Mts, Southern Carpathians (SW Romania). Contribut xii Botanice [Universitatea ‘‘Babes-Bolyai’’ Cluj-Napoca] 40: 105–110. [Report of 28 species, 20 new to the Poiana Rusca Mountains; Lecanora thysanophora new to Romania.] Bejerke, J. W. 2006. Menegazzia subsimilis (H. Magn.) R. Sant. new to the British Isles. British Lichen Society Bulletin 98: 46. [Report on several collections at the British Museum.] Bennett, J. P. 2006. Lichens in Wisconsin: the future is uncertain. Wisconsin Flora 2006(May): 4. [Short popular essay.] ———. 2006. Lichens of Wisconsin data entry project update. Wisconsin Flora 2006(May): 4–5. [Update on herbarium label data project, currently concentrating on the macrolichens (excluding Cladonia for now).] ———. 2006. New or overlooked Wisconsin lichen records. Evansia 23(2): 28–33. [Report of 58 species and 12 genera not listed in Thomson’s Lichens of Wisconsin.] Berryman, S. & B. McCune. 2006. Epiphytic lichens along gradients in topography and stand structure in western Oregon, USA. Pacific Northwest Fungi 1(2): 1–38. [‘‘We infer that remnant trees serve as refugia for lichens through a disturbance and provide lichen inoculum to younger trees. Hardwood patches were hotspots for lichen diversity, particularly cyanolichens that are infrequent on conifers. Hardwood patches were most prevalent along perennial streams. To maintain and enhance lichen communities at a landscape level, forest managers must consider the importance of features such as late-successional stands, remnant trees, hardwoods, and riparian areas to lichen communities. These features are especially important to retain in or near regenerating forests to promote colonization by dispersallimited lichens.’’ Only available online at http://pnwfungi.org/articles.htm] ——— & ———. 2006. Estimating epiphytic macrolichen biomass from topography, stand structure and lichen community data. Journal of Vegetation Science 17: 157–170. [Study conducted in the central Cascades of western Oregon. ‘‘Lichen biomass changed with elevation, cyanolichen biomass highest at low elevations (470–950 m) and forage lichen biomass highest at higher elevations (950-1470 m). Lichen biomass was lowest in even-aged young stands and highest in mature stands with remnant trees and in oldgrowth.’’] Carceres, M. & R. Lucking. 2006. Diversidade, biogeografia, ecologie e utilizacao de liquens foliicolas. Pages 519–535. In L. Xavier Filho, M. E. Legaz, C. V. Cordoba & E. C. Pereira (eds.), Biologia de Liquens. Âmbito Cultural Edicoes, Ltda., Rio de Janeiro. [Overview of diversity, biogeography and ecology of foliicolous lichens. In Portuguese.] Carlberg, T. (ed.). 2006. Bulletin of the California Lichen Society. Volume 13. No. 1. California Lichen Society, Fairfax, CA. 24 pages. [News and notes on activities of society members. Some articles are listed separately in this bibliography.] * The cumulative database for this series is available in searchable form on the World Wide Web at http://www.toyen.uio.no/botanisk/ bot-mus/lav/sok_rll.htm. I owe special thanks to Bill Buck for providing copies of papers by other authors, which were otherwise unavailable to me, and to the cooperating authors who send reprints or electronic versions of their works to me for inclusion in this series.

Two new thamnolic acid-containing Lepraria species from Thailand

Lepraria aurescens and Lepraria pulchra are described as new from bark in Thailand; both contain thamnolic acid, but differ in thallus form and colour.

Revision of the lichen genus Menegazzia in Japan, including two new species

Five Japanese species of the lichen genus Menegazzia are recorded. Menegazzia caviisidia Bjerke &amp; P. James sp. nov. is characterized by numerous globose to dactyliform to narrowly obovate, hollow isidia, small conical perforations, and thamnolic acid as the major medullary constituent. It appears to be a rare species, so far known only from three localities on Honshu. The status of the primary species M. asahinae is elucidated. Menegazzia pedicellata Bjerke sp. nov. is a rare caperatic acid-containing species previously included in M. asahinae s. lat. Menegazzia asahinae s. str. has perforated margins of apothecia and contains the stictic acid complex. Menegazzia asahinae f. subimpertusa and M. pseudocyphellata are reduced to synonymy with M. asahinae s. str. Two sorediate species are known, viz. M. subsimilis and M. terebrata.