Mount Jaya (5000 m) in Papua (Indonesian New Guinea) is the highest mountain in Malesia and 56 species of Grammitidaceae are known from it. They are listed, together with their altitude ranges, habitat types and geographic distribution. Comparisons are made with Grammitidaceae of Murkele Ridge in Seram, Moluccas, Indonesia (3000 m, 55 species), Mount Kinabalu in Sabah, East Malaysia, Borneo (4100 m, 76 species) and Gunung Mulu, Sarawak, East Malaysia, Borneo (2400 m, 43 species). A Malesia-wide core of 23 grammitid species is identified.
Trichomanes speciosum Willd. (Hymenophyllaceae) is unique amongst European ferns in that the gametophyte generation can survive indefinitely in the absence of the sporophyte, propagate vegetatively and disperse locally. Reproductive success, both in terms of spore production and sporophytic recruitment currently vary widely across the species’ broad, disjunct range, declining from south to north and west to east. Reproductive success would appear to be controlled largely by climatic factors, although genetic components also must be considered. Detailed study of populations throughout the species’ range, over a 15 year period, have led to a greater understanding of growth rates, powers of dispersal and the reproductive strategies currently operating. Using this knowledge, the extent and pattern of genetic variation regionally and locally, i.e within sites, can be used to infer the routes and mechanisms of colonisation and subsequent reproductive history. Many sites for this species have been considered as glacial refugia, i.e., supporting relictual populations through cycles of glaciation throughout the Tertiary. The validity of these claims is tested using molecular and other data.
The neotropical genus Danaea is in revision and some notes on the genus are presented here. We find that the genus can be divided into three subgroups, based on morphological characters of the rhizome, stipe articulation and pinna margin serration. The tree groups are discussed and some taxonomic issues are addressed. The occurrence of bipinnate D. nodosa is reported from Jamaica, and trifoliate specimens of D. simplicifolia are reported from French Guiana. The identities of D. alata, D. jamaicensis, D. jenmanii, D. mazeana, D. media, D. nodosa, D. trifoliata and D. ulei and their synonyms are discussed. Further studies on the phylogeny, taxonomy and ecology of Danaea are needed.
A long-term demographic study to assess temporal variation in two common New England ferns, Dryopteris intermedia (Evergreen wood fern) and Polystichum acrostichoides (Christmas fern) focused on fertile leaf production by the reproductively mature sporophyte. Over an eight-year period only 29.9% of the leaves in a D. intermedia crown were fertile, while for P. acrostichoides significantly more (48.0%) of the leaves in the crown were fertile. Annual values of the percentage of plants with fertile leaves for D. intermedia ranged from 42% to 77% and for P. acrostichoides from 57% to 93% reflecting significant annual variation, possibly related to winter weather conditions. Only 16% of D. intermedia and 14% of P. acrostichoides sporophytes were fertile every year of the study. Transitions from fertile plant status to sterile plant status occurred in 15% of the D. intermedia observations and 14% of the P. acrostichoides observations. For both species, when a sterile year followed a fertile year the number of leaves in the crown decreased by approximately half a leaf. Determining the causes of such high levels of variability in plant fertility will be necessary before the role of ferns in any ecosystem can be fully understood.
This paper summarises our continuing study of the evolutionary history of Asplenium in New Zealand. Chloroplast DNA sequence data and AFLP DNA-fingerprinting have been used to examine the origins and relationships of the New Zealand Asplenium taxa, to test species boundaries, and to further investigate the ancestry of the octoploid Asplenium taxa belonging to the Austral group.