The Fern Gazette Volume 17 Part 3

Published 15th September 2005

Edited by M. Gibby & A. Leonard


Floristics in the 21st Century: balancing user-needs and phylogenetic information
A.R. Smith pg(s) 105-137
The status of floristic work on pteridophytes around the world is reviewed. Relatively modern floras exist for most temperate and Mediterranean areas, including Europe, the former Soviet Union, North America north of Mexico, Chile, South Africa, and Australia, but are absent, partial, or outdated for many, if not most, tropical and subtropical countries/regions. Exceptions in the New World include Mexico, Mesoamerica, and certain of the Antilles. For many areas we have only annotated checklists (e.g., Tropical East Africa, Malaysia, Mount Kinabalu) or partially written floras (Ecuador, Malesia). Modern treatments for island floras are also few, exceptions being for New Zealand (Brownsey & Smith-Dodsworth, 2001), Hawaii (Palmer, 2003), and the Mariana Islands (Raulerson & Rinehart, 1992). Floristic “hotspots”, e.g., Colombia, Brazil, Madagascar, New Guinea, and the Himalayas, often have inadequate or incomplete modern accounts. Treatments of the ferns are planned or in progress for many countries, including Venezuela, Bolivia, East Africa, and China, but these often proceed at a painstakingly slow pace. Local florulas, such as for Barro Colorado Island in Panama, complement larger regional floras while serving different, but overlapping, purposes; Flora Guaramacal (Venezuela), Central French Guiana (Saül), and the Hong Kong flora are notable examples. Ideally, modern pteridofloras should incorporate recent phylogenetic conclusions at various ranks (especially family, genus), multi-access keys, comments on relationships and taxonomic problems, and references to phylogenetic literature, coupled with access to online data-bases (interactive keys, gazetteers, publication data, distribution maps, images and photographs, specimen citations, trees of relationship, and links to pertinent websites). Two families usually considered “fern allies”, Psilotaceae and Equisetaceae, are now thought to be intimately related to basal ferns, and this evidence needs inclusion into floristic literature. Many traditional genera (e.g., Asplenium, Pellaea, Polypodium, Pteris) need substantial recircumscription to meet criteria of monophyly or even paraphyly in floras. The dwindling number of people with broad expertise in floristics, fern systematics, and identification seriously constrains the creation of modern floras, and is expected to be an increasing problem in the future.
Noteworthy fern discoveries in the Philippines at the turn of the 21st Century
J. F. Barcelona pg(s) 139-146
The status of pteridological research in the Philippines at the turn of the 21st century is presented and discussed. An electronic database containing collection and taxonomic information on nearly 23,000 collection numbers of Philippine pteridophyte specimens in herbaria around the world was started in 1994, a collaborative personal and institutional endeavor. I also provide a synthesis of the results of my field explorations in three protected areas in the last three years. Noteworthy of these are the rediscovery and confirmation of the presence in the Philippines of the genus Cyrtomium, and the rediscovery of Aglaomorpha cornucopia, Antrophyum williamsii, Ctenitis humilis, and Dennstaedtia macgregori, rare Philippine endemics. The need for extensive botanical explorations in the Philippines is imperative for our understanding of biodiversity and sound conservation management. The implications for scientific research and cooperation of current laws regarding biological collection and transport, especially the Wildlife Resources Conservation and Protection Act, are also presented .

Molecular phylogenetic study on Davalliaceae
C. Tsutsumi & M. Kato pg(s) 147-162
In previous classifications based on morphological characters, Davalliaceae comprises from four to ten genera, whose concepts differ among authors. This study analyzed a molecular phylogeny of 36 species in five genera. Deduced phylogenetic relationships based on a combined dataset of five continuous chloroplast regions, atpB, rbcL, accD, atpB-rbcL spacer, and rbcL-accD spacer, are incongruent to any previous classifications, and none of the genera are monophyletic. Araiostegia is divided to two clades, one of which is the most basal and includes Davallodes, and the other is nested within the rest of the family. Davallia is divided into three clades, in accordance with three sections classified mainly by scale morphologies, and the clades are separated by the intervention of a clade of Araiostegia, Humata and Scyphularia. Humata and Scyphularia are also paraphyletic.

Development of gametophytes from gemmae of Killarney Fern (Trichomanes speciosum Willd., Hymenophyllaceae, Pteridophyta)
K. Makgomol & E. Sheffield pg(s) 163-177
Trichomanes speciosum Willd. (Hymenophyllaceae) is one of the rarest species in the British Isles. One aim of the research programme of which this study formed a part was to understand the requirements for, or tolerance of, extremely deep shade by T. speciosum gametophytes. A specific aim was to determine the extent to which macro- and micro-morphological features, in particular reproduction via gemmae, might contribute to the success of this species in deep shade habitats. Another specific aim was to understand how gametophyte growth is affected by different light and temperature conditions. Gemmae are highly variable in cell number and shape, but typically spindle-shaped or bar-shaped. Once detached, there is no set pattern of growth but photosynthetic cells are typically formed before rhizoids. The highest numbers of photosynthetic cells were produced by gemmae grown in the lowest light level employed in the study: 5µmolm-2s-1, PAR. Most gemmae proved unable to grow in 60 or 90µmolm-2s-1. Gemmae grown at 24°C generated the greatest number of photosynthetic cells and rhizoids in the temperature tested; those grown at 28°C produced the fewest in both light levels tested (5 and 30µmolm-2s-1 PAR). Of the conditions tested, PAR of 5µmolm-2s-1 and a temperature of 24°C generated optimum gametophyte growth from gemmae cultured on the media used. This is significantly higher than the ambient light levels and temperatures found for most of the time in British field sites, and in line with predictions for a sub-tropical species on the edge of its range. Implications for site and climate perturbation are discussed.


Ferns for the 21st Century
M. Gibby, A. Leonard & H. Schneider (Eds.) pg(s) 101-104


The pteridphytic diversity in the cloud montane forests from Salta, NW Argentina
E.R. de la Sota & O.G. Martínez pg(s) 138

Fungistatic activity of internal secreting hairs of Dryopteris rhizomes
E.K. Zenkteler & H. Kwaÿna pg(s) 178

Pteridophyte diversity along a gradient of disturbance within and near abandoned opencast mines in Thong Pha Phum District, Kanchanaburi Province, Thailand
A. Sathapattayanon & T. Boonkerd pg(s) 179
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