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Featured researches published by Josef Poelt.


Plant Systematics and Evolution | 1987

Über Cyanotrophie bei Flechten

Josef Poelt; Helmut Mayrhofer

AbstractIn contrast to the well-known blue-green algal containing lichens several green algal containing lichens, belonging to very different genera, show regular connections to free-living or ± lichenized blue-green algae, mainlyStigonema. Most of these lichens have squamulose thalli. This lichen-algal relationship, regarded as cyanotrophy, may be either facultative or obligate. Some of the species occur only on very poor, acidic rocks onStigonema, while they occur independent ofStigonema in high nutrient biotops. Obligate species cover the blue-green algae with hyphae and some of these species cover the algae so extensively that one can call these connections paracephalodia. — Two species and one variety are new to science from the mainly Himalayan genusBryonora. They occur in high elevations in Nepal and are cyanotrophic.Bryonora selenospora has thick, halfmoon-shaped to slightly twisted ascospores. The other two new taxa areB. reducta andB. rhypariza var.cyanotropha. There are several other cyanotrophic lichen taxa besides the ones described here. They will be introduced at a later occasion.


Plant Systematics and Evolution | 1985

Zwergstrauchige Arten der FlechtengattungCaloplaca

Josef Poelt; U. Pelleter

The frutescent species of the lichen genusCaloplaca are usually united in sect.Thamnoma, but they do not form a natural group. They are derived from different species groups within sect.Gasparrinia from different parts of the world, presumable from species having scleroplectenchymes in cortex and medulla. The algal cells are concentrated between the scleroplectenchymatic strands in large and dense groups, from where medullary plectenchyme extends to the cortex and forms characteristic pseudocyphellae there.—Most of the species seem to be ornithocoprophilous; they grow on rocks along marine coasts where much fog is induced by cold currents.—Caloplaca cribrosa is endemic in Tasmania and New Zealand,C. regalis and the doubtfulC. ambitiosa belong to the antarctic element.C. fragillima from central Chile seems to be propagated by thallus fragments.C. coralloides andC. thamnodes are endemic to California and Baja California respectively.C. cladodes from the Rocky Mountains deviates in many characteristics from the other species i.a. by it different ontogenetic development, reduced spore septum, and cementing amyloid polysaccharides within the scleroplectenchymatic strands. The African species are characterized by their distinctly dorsiventral lobes and usually possess oil cells in some of the paraphyses.Caloplaca bonae-spei, C. fragillima andC. thamnodes are new to science.


Plant Systematics and Evolution | 1986

Five additional genera of conidial lichen-forming fungi from Europe

David L. Hawksworth; Josef Poelt

Three remarkable new genera of conidial lichen-forming fungi, with pycnidial or acervular conidiomata are described and illustrated.Hastifera tenuispora gen. et spec. nov. from the South-Tyrol, Italy, is characterized by very long and narrow hyaline conidia produced in pycnidial conidiomata immersed in thalline warts.Lichingoldia gyalectiformis gen. et spec. nov. from rocks subject to inundation by freshwater in Norway has long sigmoidly curved conidia which appear to be adapted to dispersal in water.Woessia fusarioides gen. et spec. nov. from aQuercus stump in the Burgenland, Austria, has a finely granular thallus and disc-like conidiomata producing falcate conidia; this species is also of interest in that it hasChlorella as the photobiont. The recently described hyphomyceteCheiromycina flabelliformisB. Sutton is reported from Austria for the first time, and is also lichenized. Recent collections ofNigropuncta rugulosaD. Hawksw. from Austria and Italy also show that this species is lichenized rather than parasymbiotic. In all five cases the fungal hyphae of the conidiogenous structures are continuous with those in intimate contact with cells of the algal partners and the biological relationship appears to be mutualistic giving rise to stable crustose lichen thalli.


Folia Geobotanica Et Phytotaxonomica | 1987

Electensystematische Studien XII Die FamilieGomphillaceae und ihre Gliederung

Antonín Vězda; Josef Poelt

The originally monotypic familyGomphillaceaeW. Wats. exHaf. 1984 (Type=GomphillusNyl.) is here enlarged to accomodate nine additional genera:AulaxinaFée,CaleniaMüll. Arg. emSant.,EchinoplacaFée em.Sant.,GyalectidiumMüll. Arg.,GyalideopsisVězda,TrichariaFée em.Sant. (all previously considered as a group of related genera in the familyAsterothyriaceae), andActinoplacaMüll. Arg., as well as two new genera described here,BullatinaVêzda etPoelt andCaleniopsisVězda etPoelt. Particular attention is given to the diversity of the structure of the hyphophores which are specific to all the genera now included in the familyGomphillaceae and therefore assist in the accurate delimitation of these genera. A short description of each genus is appended, together with a list of species included. A key to the genera is presented and their interrelationships discussed.


Plant Systematics and Evolution | 1982

Caloplaca sect.Xanthoriella, sect. nov.: Untersuchungen über die „Xanthoria lobulata-Gruppe“ (Lichenes,Teloschistaceae)

Maximilian Steiner; Josef Poelt

Reexamination ofXanthoria persica, X. polycarpoides, X. lobulata gave evidence, that the thalli of these species are devoid of a lower cortex and rhizinae. Therefore, they do not fit the definition of the genusXanthoria and are transferred toCaloplaca (under the new sectionXanthoriella) asCaloplaca persica, C. polycarpoides, andC. boulyi, respectively. — Details on development, anatomical structure, ecology and distribution are presented.


Plant Systematics and Evolution | 1974

Die parasitische FlechteLecidea insidiosa und ihre Biologie

Josef Poelt

Lecidea insidiosa, up to now regarded as a lichenicolous fungus without thallus, is a parasitic lichen, growing exclusively onLecanora varia. It kills the plectenchyma of the host, but presumably takes over part of the host-algae to build its own thallus, first inside, then outside of the host thallus. Host and parasite thallus are chemically different.Lecidea insidiosa is not related toLecidea vitellinaria, even though the two were thought to be synonymous for a long time. The species is reported for the first time from the Alps (Steiermark). It is the first known parasitic lichen to occur on a normally wood inhabiting host.


Plant Systematics and Evolution | 1981

Arthopyrenia endobrya, spec. nov., eine hepaticole Flechte mit intrazellulärem Thallus aus Brasilien

Peter Döbbeler; Josef Poelt

Arthopyrenia endobrya from Southern Brazil is illustrated and described as a new species of lichens. The thallus is composed of filamentous green algae loosely surrounded by fungal hyphae. Both symbionts grow endophytically within the leaf cells of two species ofLejeuneaceae (Hepaticae). The algae and hyphae penetrate the cell walls of the host by means of fine perforations. The ascocarps develop between the leaves and perforate them with their apical region. The classification as a member of the genusArthopyrenia is preliminary.


Plant Systematics and Evolution | 1978

Über Nord-Süd-Gradienten von Chemotypen europäischer Flechten

Ch. Leuckert; Josef Poelt

In Europe the chemotypes in different lichen groups tend to be distributed not randomly but along a north-south gradient. In the south more numerous and more complex chemotypes occur. In the north there are fewer chemotypes, often with fewer substances involved, or strains lacking certain compounds (0-strains). This gradient is established through chemical differentiation according to colourless substances of the medulla (group I), pigments of the cortex (group II), a combination of both in the same thallus (group III), and pigments in the medulla (group IV). The north-south gradient is found in lichens of very diverse families and genera, at least among species that are saxicolous, crustose or lobate but not sorediate. This gradient should not be interpreted as a consequence of relatively recent evolution but rather of increasing impoverishment in northern regions due to glaciation periods and the climatic conditions prevailing up to the present time.


Plant Systematics and Evolution | 1980

Eine diözische Flechte

Josef Poelt

The lichenLecidea verruca, growing parasitically on other crustaceous lichens, is, contrary to most other lichenized ascomycetes, dioecious. The male thalli bearing spermogonia are mostly smaller than the female ones.


Plant Systematics and Evolution | 1976

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

Josef Hafellner; Josef Poelt

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

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Antonín Vězda

Czechoslovak Academy of Sciences

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