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1.
Barbara S. Parris 《Brittonia》2001,53(2):270-283
Four major austral continental distribution patterns are evident in pteridophytes. Twenty-two species are completely circum-Antarctic.
Another 39 species are partially circum-Antarctic, occurring in Australasia (Australia and New Zealand) and Africa (including
Madagascar) but not South America, while 29 are in Africa and South America but not Australasia, and 13 are in South America
and Australasia but not Africa. Two hypotheses are considered as explanations for the patterns: continental drift following
the breakup of Gondwana and long-distance dispersal. Fossil evidence indicates that the majority of pteridophyte families
involved appeared after the southern continents had drifted apart, so long-distance dispersal is likely to explain the distribution
of species in these families on now widely separated continents. For those families extant before the break-up, there is no
indication in the fossil record that the species involved were present in Gondwana. Aspects of the ecology of the species
that are partly or completely circum-Antarctic indicate that long-distance dispersal, rather than continental drift, is a
likely explanation for the patterns. 相似文献
2.
J. Mitchell McGrath Leslie G. Hickok Eran Pichersky 《Plant Systematics and Evolution》1994,189(3-4):193-202
We have used cDNA clones as probes on Southern blots to detect restriction fragment length polymorphisms among sevenCeratopteris thalictroides accessions, threeC. richardii accessions, and one putative interspecific hybrid. We found that the stringency of post-hybridization washes was a critical parameter affecting the quality of our blots; even with homologous cDNA sequences low stringency conditions resulted in a smear of signal, but high stringency washes gave blots with distinct bands. Most probes showed hybridization with four or more genomic fragments. Similarities in the number and size of fragments between and within species indicated that (i)C. richardii shows limited polymorphism among accessions tested, (ii)C. thalictroides is highly polymorphic, and (iii) Hawaiian accessions ofC. thalictroides are divergent relative to their continental cohorts and among themselves. The putative interspecific hybrid did not group closely with either of these species. 相似文献
3.
DAVID H. LORENCE 《Botanical journal of the Linnean Society. Linnean Society of London》1978,76(3):207-247
A survey of the pteridophytes of Mauritius is presented, including a summary of their habitats, ecology, and phytogeographical affinities. Of the 186 infrageneric taxa recorded from the island, 8 are adventive or naturalized, and 27 are presumed rare or extinct. Major ecological groupings are presented and species are listed for both indigenous and secondary plant communities. 相似文献
4.
As a result of our work on the Lycopodiaceae account for the Critical Flora of Italy, a new, synonymic inventory of Italian taxa is presented, based on herbarium studies and critical re-examination of extant literature. Three genera with eight species are accepted: Huperzia (1 species), Lycopodiella (1), and Lycopodium (6). An additional, ninth species (Lycopodiella cernua) is listed as a casual alien. The genus Diphasiastrum, accepted in several recent works, is treated at sectional level within Lycopodium (three species and their three hybrids). Lycopodium lagopus ( = L. clavatum subsp. monostachyon) is a recent addition to the Italian flora. Images of five types and Internet URI of other six types are supplied. Dot distribution maps and a dichotomous key to Italian species are provided. It is shown that the family name Urostachyaceae (a family here not separated from Lycopodiaceae) was validly published and has priority over Huperziaceae, for which the oldest name, however, would be Phylloglossaceae. 相似文献
5.
An annotated synonymic inventory of Italian Selaginella taxa, a practical key for their identification and their dot distribution maps are presented, as a result of our work on the Selaginellaceae account for the Flora Critica d'Italia. The names Lycopodium helveticum L. and Selaginella denticulata var. platystachya Hieron. are typified. 相似文献
6.
Pollen and spores recovered from three cores of Holocene to recent deposits from the island of Saipan indicate the presence of mangrove vegetation, including Bruguiera and Acrostichum, on the island previous to World War II. The occurrence of Casuarina equisetifolia Linneaus 1759, from cores elsewhere on the island of Saipan, at depths predating the arrival of humans to the island, suggest that this tree species is endemic to Saipan rather than a recent invasive species. These findings will assist in replanting native vegetation once destroyed through wartime activities on the island. 相似文献
7.
8.
SAMULI LEHTONEN HANNA TUOMISTO GERMINAL ROUHAN MAARTEN J. M. CHRISTENHUSZ 《Botanical journal of the Linnean Society. Linnean Society of London》2010,163(3):305-359
The classification and generic definition in the tropical–subtropical fern family Lindsaeaceae have been uncertain and have so far been based on morphological characters only. We have now studied the evolutionary history of the Lindsaeaceae by simultaneously optimizing 55 morphological characters, two plastid genes (rpoC1 and rps4) and three non‐coding plastid intergenic spacers (trnL‐F, rps4‐trnS and trnH‐psbA). Our data set included all genera associated with Lindsaeaceae, except Xyropteris, and c. 73% of the currently accepted species. The phylogenetic relationships of the lindsaeoid ferns with two enigmatic genera that have recently been included in the Lindsaeaceae, Cystodium and Lonchitis, remain ambiguous. Within the monophyletic lindsaeoids, we found six well‐supported and diagnostic clades that can be recognized as genera: Sphenomeris, Odontosoria, Osmolindsaea, Nesolindsaea, Tapeinidium and Lindsaea. Sphenomeris was shown to be monotypic; most taxa formerly placed in that genus belong to the Odontosoria clade. Ormoloma is embedded within Lindsaea and therefore does not merit recognition as a genus. Tapeinidium is sister to a clade with some species formerly placed in Lindsaea that are morphologically distinct from that genus and are transferred to Osmolindsaea and Nesolindsaea, proposed here as two new genera. We do not maintain the current subgeneric classification of Lindsaea itself, because neither of the two generally accepted subgenera (Lindsaea and Odontoloma) is monophyletic, and most of the sections also appear unnatural. Nesolindsaea shows an ancient biogeographical link between Sri Lanka and the Seychelles and many of the main clades within Lindsaea have geographically disjunct distributions. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 305–359. 相似文献
9.
Diffusional limitations explain the lower photosynthetic capacity of ferns as compared with angiosperms in a common garden study 下载免费PDF全文
M. CARRIQUÍ H. M. CABRERA M. À. CONESA R. E. COOPMAN C. DOUTHE J. GAGO A. GALLÉ J. GALMÉS M. RIBAS‐CARBO M. TOMÁS J. FLEXAS 《Plant, cell & environment》2015,38(3):448-460
Ferns are thought to have lower photosynthetic rates than angiosperms and they lack fine stomatal regulation. However, no study has directly compared photosynthesis in plants of both groups grown under optimal conditions in a common environment. We present a common garden comparison of seven angiosperms and seven ferns paired by habitat preference, with the aims of (1) confirming that ferns do have lower photosynthesis capacity than angiosperms and quantifying these differences; (2) determining the importance of diffusional versus biochemical limitations; and (3) analysing the potential implication of leaf anatomical traits in setting the photosynthesis capacity in both groups. On average, the photosynthetic rate of ferns was about half that of angiosperms, and they exhibited lower stomatal and mesophyll conductance to CO2 (gm), maximum velocity of carboxylation and electron transport rate. A quantitative limitation analysis revealed that stomatal and mesophyll conductances were co‐responsible for the lower photosynthesis of ferns as compared with angiosperms. However, gm alone was the most constraining factor for photosynthesis in ferns. Consistently, leaf anatomy showed important differences between angiosperms and ferns, especially in cell wall thickness and the surface of chloroplasts exposed to intercellular air spaces. 相似文献
10.
Scott Zona Maarten J. M. Christenhusz FLS 《Botanical journal of the Linnean Society. Linnean Society of London》2015,179(4):554-586
Litter‐trapping plants have specialized growth habits and morphologies that enable them to capture falling leaf litter and other debris, which the plants use for nutrition after the litter has decayed. Litter is trapped via rosettes of leaves, specially modified leaves and/or upward‐growing roots (so‐called ‘root baskets’). Litter‐trappers, both epiphytic and terrestrial, are found throughout the tropics, with only a few extra‐tropical species, and they have evolved in many plant families. The trapped litter mass is a source of nutrients for litter‐trapping plants, as well as food and housing for commensal organisms. Despite their unique mode of life, litter‐trapping plants are not well documented, and many questions remain about their distribution, physiology and evolution.–© 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 554–586. 相似文献