Riassunto Scopo principale di questo lavoro e l'illustrazione per mezzo del microscopio a scansione, delle spore delle Pteridofite spontanee in Italia. Queste ammontano a 124 taxa specifici ed infraspecifici, le cui spore sono illustrate da 550 micrografie (3–8 per ogni taxon) radunate in 71 tavole. Il lavoro consiste di una prefazione, una introduzione e quattro parti del testo vero e proprio. La prefazione e principalmente destinata a spiegare lo scopo del lavoro ed a ringraziare gli amici e colleghi che ci hanno offerto gentilmente aiuto nella nostra ricerca. L'introduzione e rivolta a dare alcune informazioni generali e dettagli sull'inquadramento tassonomico delle Pteridofite italiane, delle quali viene dato un elenco completo, sui materiali e metodi per il nostro studio, e sulle ricerche per reperire i dati citologici e geobotanici. La prima parte fornisce i dati relativi a ciascuna specie e sottospecie, eccezionalmente varieta, studiate nel nostro lavoro. Essi consistono di varie informazioni suddi...

Iconographia Palynologica Pteridophytorum Italiae

Apomixis and reticulate evolution in the Asplenium monanthes fern complex

Macaronesia, which includes five mid-Atlantic archipelagos (Azores, Madeira, Selvagems, Canaries, and Cape Verdes), has been traditionally recognized as a distinct biogeographic unit whose circumscription has been intimately associated with the hypothesis that the flora is a relict of a formerly broadly distributed subtropical Tertiary flora. The concept of Macaronesia is revisited here using parsimony and Bayesian analyses of floristic data sets for the moss, liverwort, and pteridophyte floras. All analyses reject the monophyly of Macaronesia s.l., resolving the Cape Verdes with tropical Africa. Of the other Macaronesian archipelagos, the liverwort and pteridophyte analyses support, or could not reject, an Azorean-Madeiran-Canarian clade (hereafter Macaronesia s.s.), but the moss analysis resolves the Canary Islands as sister to North Africa, thus rejecting the concept of Macaronesia s.s. for this group. Dynamic interchange of taxa with neighboring continental areas rather than relictualism best explains the relationships of the Cape Verde cryptogamic flora and the Canary Island moss flora. In contrast, relictualism is consistent with a monophyletic Macaronesia s.s. for liverworts and pteridophytes. However, from the limited information available on relationships of endemic cryptogams, this explanation alone may be unsatisfactory. Spatially congruent patterns may, in fact, conceal a complex mixture of relictual distributions and more recent speciation and dispersal events.

Does Macaronesia exist? Conflicting signal in the bryophyte and pteridophyte floras

Distant hybridization refers to crosses between two different species, genera, or higher-ranking taxa, which can break species limits, increase genetic variation, and combine the biological characteristics of existing species. It is an important way of creating genetic variation, fertile strains, and excellent characteristics in new strains and populations. Combining analyses and summaries from many inter-related documents in plants and animals, both domestic and international, including examples and long-standing research on distant hybridization in fish from our laboratory, we summarize and compare the similarities and differences in plant and animal distant hybridization. In addition, we analyze and review the biological characteristics of their different ploidy progenies and the possible causes of disparity in survival rates. Mechanisms of sterility in animal and plant distant hybrids are also discussed, and research methods for the study of biological characteristics of hybrids, including morphology, cytology, and molecular cytogenetics are presented. This paper aims to provide comprehensive research materials and to systematically compare the general and specific characteristics of plant and animal hybrids with regards to reproduction, genetics, growth traits, and other biological characteristics. It is hoped that this paper will have great theoretical and practical significance for the study of genetic breeding and biological evolution of plant and animal distant hybridization.

A comparative study of distant hybridization in plants and animals

To test earlier hypotheses on the evolutionary origins of European polyploid Dryopteris, their phylogenetic rela- tionships are investigated using nuclear pgiC and plastid trnL-F sequence data. The nuclear pgiC region is for the first time used successfully in phylogenetic analyses of ferns, and is shown to provide appropriate variability to address species-level questions in Dryopteris. The trnL-F dataset is used to infer maternal relationships for the allopolyploid species and provides strong support for some of the smaller clades resolved by pgiC. Allopolyploid origins of Dryopteris carthusiana, D. cristata, and D. guanchica are supported and some, but not all, progenitors are indicated by the analyses. The results are in disagreement with the "D. semicristata" hypothesis proposed by several authors. The allopolyploid origin of D. crispifolia remained unresolved and allopolyploid origins of D. dilatata and D. filix-mas were unsupported. This study provides the first insight in the molecular phylogeny of the diploid D. fragrans, which shows major genetic variation within the only European population of the species.

Relationships and evolutionary origins of polyploid Dryopteris (Dryopteridaceae) from Europe inferred using nuclear pgiC and plastid trnL-F sequence data

The genus Dryopteris in the Canary Islands and Azores and the description of two new tetraploid species

Asplenium trichomanes L. is an aggregate species of world-wide distribution. Diploid, tetraploid, and hexaploid (in Australia and New Zealand) cytotypes are known, the first two of which are polymorphic. Only a few of these forms have botanical names. We use here the nomenclature and typification of Lovis (1964). Love and Kjellqvist (1972) and Love and Love (1974) suggested assigning specific rank to the diploid and tetraploid cytotypes, following Rothmaler (1966, p. 5) and So6 in Fuchs (1963). In principle this is acceptable, but it is very impractical because there are many cases in which even specialists are unable to differentiate between the cytotypes with confidence when dealing with herbarium material. According to Carvalho e Vasconcellos (1968), both the diploid A. trichomanes subsp. trichomanes (sensu Lovis, 1964) and the tetraploid subsp. quadrivalens D. E. Meyer (1962) are assumed to grow in the Azores, but Pinto da Silva in Palhinha (1966) was more cautious. He quoted Lovis' opinion of that time: "However, the only form of A. trichomanes from Azores yet studied alive is a peculiar form, and requires more study before it can be given an accurate taxonomic treatment." Franco (1971, p. 23) did not differentiate between the subspecies. Wilmanns and Rasbach (1973, p. 326) stated that most specimens differ from Central European A. trichomanes subsp. quadrivalens by brightness, longer pinnae, and stronger teeth. Sjogren (1973, p. 85), Eriksson et al. (1974, p. 1), and Pinto da Silva and Pinto da Silva (1974, p. 14) reported only subsp. quadrivalens for the Azores. Of related species in the Azores, all authors mention A. monanthes L. The following also report A. anceps Lowe ex Hook. & Grev.: Bolle (1866, p. 215), Milde (1867, p. 64, sub A. trichomanes var. anceps f. azorica), Drouet (1866, p. 131), Sauer (1880, p. 43), Trelease (1897, p. 172, sub A. trichomanes var. anceps f. azorica), Palhinha (1943) and Benl and Sventenius (1970, p. 447). We suspect that all these reports are wrong because of confusion with A. azoricum. We have not seen the specimen that Bolle quoted, but he stated that the only specimen from the Azores he had seen, which was collected by A. Braun, showed a more pronounced dentation at the tip and acroscopic side of the pinnae. This is typical ofA. azoricum, and we suspect that his specimen was indeed that species. Milde's type and sole specimen is A. azoricum. Sauer did not mention any specimens, but cited only "Azores." We have seen two specimens of Drouet (BM), 11 out of the 19 specimens cited by Trelease, and all five quoted by Palhinha. None is A. anceps. Benl and Sventenius based their record of A. anceps on the literature mentioned above (Benl, in litt.). So far we have been unable to detect any specimen of A. anceps from the Azores in any herbarium.

Asplenium azoricum and Other Ferns of the A. trichomanes Group from the Azores

Cheilanthes guanchica Bolle in Europa

Die Farnpflanzen Zentraleuropas : Gestalt, Geschichte, Lebensraum

Summary Both, Asplenium petrarchae (Guerin) DC. and A. trichomanes L. are aggregate species that comprise diploid and tetraploid cytotypes. In A. trichomanes additionally a rare hexaploid cytotype exists. So far, two different hybrids between these aggregates are known, one being triploid, the other tetraploid. The triploid hybrid, with the genome formula PePeTr, results from a cross between A. petrarchae subsp. petrarchae and A. trichomans L. subsp. inexpectans Lovis. It was validly published as A. x litardierei by BENNERT & MEYER (1974) but an earlier name, A. x helii, was published by LUSINA in 1943; it therefore deserves priority and represents the correct name. The hybrid described as A. x nieschalkii by MEYER (1963) is not tetraploid as he incorrectly claimed but triploid; as we show now, it represents the same nothotaxon as A. x helii. The truely tetraploid hybrid has so far been found only twice but at virtually the same locality (near Benaojan, southern Spain). We have recently proposed the name ...

Asplenium x helii Lusina, the valid name for the hybrids between A. petrarchae (Guérin) DC. and A. trichomanes L. (Aspleniaceae, Pterido-phyta). II. Detailed description and illustrations

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