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101.

Background and Aims

Farfugium (Asteraceae) is a small genus that contains the two species F. japonicum and F. hiberniflorum and is distributed along a long archipelago in east Asia. The common taxon, F. japonicum, includes three varieties associated with a wide range of habitats, including forest understorey (sciophytes), coastal crag (heliophytes) and riverbed (rheophytes). Leaf shape is an important taxonomic character within this genus and is associated with the habitat.

Methods

Twenty populations that included all Farfugium taxa were collected throughout its range. Leaf morphology was measured to determine differences amongst the taxa. Phylogenetic analyses based on sequences of the internal transcribed spacer of nuclear rDNA and four plastid DNA regions (matK, trnL-trnF, trnH-psbA and rpl20-rps12) were conducted separately.

Key Results

Leaf morphology was significantly different amongst taxa, but morphological variations were partly explained by adaptation to certain environmental conditions that each population inhabited. Molecular phylogenies for the nDNA internal transcribed spacer and cpDNA were consistent in classifying F. hiberniflorum and the Taiwanese var. formosanum, whilst suggesting polyphyletic origins for the rheophyte, sciophyte and heliophyte taxa. All samples from the southern Ryukyus (Japan) and Taiwan clustered into a monophyletic group, which corroborates the land configuration theory involving Quaternary land-bridge formation and subsequent fragmentation into islands. The incongruence between the two DNA datasets may imply traces of introgressive hybridization and/or incomplete lineage sorting.

Conclusions

The occurrence of rheophyte, sciophyte and heliophyte plants within Farfugium may be attributable to their isolation on islands and subsequent adaptation to the riparian, coastal crag and forest understorey environments, following their migration over the Quaternary land-bridge formation along their distribution range. Nearly identical DNA sequences coupled with highly divergent morphologies amongst these taxa suggest that diversification was rapid.  相似文献   
102.
A long term observation on biodiversity and biomass of benthic macroalgae in Point 1 of the intertidal zone of the Nanji Islands, Zhejiang were carried out during 1959–2007, including three phases, i.e. 1959–1965, 1980–1985 and 2000–2007. The results show that the species of the benthic macroalgae there disappeared by 41.7%, and decreasing trend of the biodiversity has been getting quick; the community structure clearly shifted, i.e. the proportion of subtropical and warm-temperate species increased, and that of cold-temperate species decreased in the benthic macroalgae assemblage, particularly the calcareous nullipore became an absolutely dominant group. In comparison with the second phase (1980–1985), during the third phase the average annual biomass of the benthic macroalgae decreased by 52.5%; the average spring and winter biomass decreased by 54.1% and 87.2%; while the average summer and autumn biomass increased by 11.1% and 3.2%, respectively. The causes of the decrease in the biodiversity have been discussed, and the authors considered that the climate change and increase in CO2 concentration have been the main reasons to lead berserk growth of the nullipore, resulting in desertification tendency of the intertidal zone of the Nanji Islands.  相似文献   
103.
Twenty breadfruit cultivars growing in afield genebank at Kahanu Garden, National Tropical Botanical Garden, Hana, Maui, Hawaii, were evaluated for sensory attributes and nutrient composition. A taste panel scored eight flavor/aroma attributes, five textural attributes, and color. There were significant differences (P ≤ 0.01) in aroma, visual texture, flavor intensity, sweetness, starchiness, moistness, stringiness, firmness, and color. The greatest differences were in color and texture. Nutrient analyses showed significant differences (P ≤ 0.05) for energy, carbohydrates, ash, crude protein, potassium, magnesium, sodium, iron, copper, and zinc. Considering the versatility of breadfruit as a food, its ease of production, and its nutritional value, the numerous good quality flavorful cultivars available should be more widely grown for sustainable agriculture and food security.  相似文献   
104.
In a recent paper, two of us discussed diversity patterns and diversification processes in the Azores flora. Triantis et al. (2012, Journal of Biogeography, 39, 1179–1184) challenged our hypothesis that palaeoclimatic differences had an effect on diversification rates and suggested that area, island age and isolation explain diversity patterns. They did not, however, fully address the results from our subsequent paper, in which we showed that diversity patterns evident from phylogeographic studies differ markedly from those suggested by checklists. Checklists are working hypotheses and we suggest that the discrepancies evident between molecular data and checklists may be indicative of deficiencies in our taxonomic understanding of the Azores flora. Patterns of molecular and morphological diversity need to be better understood, and the discrepancies between checklists and molecular data accounted for, before we can establish the relative importance of factors such as palaeoclimate, area, island age or isolation in generating endemic diversity patterns in the Azores flora.  相似文献   
105.
To examine the indirect effects of fishing on energy allocation in non-target prey species, condition and reproductive potential were measured for five representative species (two-spot red snapper Lutjanus bohar, arc-eye hawkfish Paracirrhites arcatus, blackbar devil Plectroglyphidodon dickii, bicolour chromis Chromis margaritifer and whitecheek surgeonfish Acanthurus nigricans) from three reef-fish communities with different levels of fishing and predator abundance in the northern Line Islands, central Pacific Ocean. Predator abundance differed by five to seven-fold among islands, and despite no clear differences in prey abundance, differences in prey condition and reproductive potential among islands were found. Body condition (mean body mass adjusted for length) was consistently lower at sites with higher predator abundance for three of the four prey species. Mean liver mass (adjusted for total body mass), an indicator of energy reserves, was also lower at sites with higher predator abundance for three of the prey species and the predator. Trends in reproductive potential were less clear. Mean gonad mass (adjusted for total body mass) was high where predator abundance was high for only one of the three species in which it was measured. Evidence of consistently low prey body condition and energy reserves in a diverse suite of species at reefs with high predator abundance suggests that fishing may indirectly affect non-target prey-fish populations through changes in predation and predation risk.  相似文献   
106.
A gall midge that induces thick lenticular galls on leaflets of Pueraria species (Fabaceae) in Japan, mainland China, Taiwan and South Korea is described as Pitydiplosis puerariae sp. nov. (Diptera: Cecidomyiidae). Tanaostigmodes puerariae (Hymenoptera: Tanaostigmatidae), described earlier from mainland China as an inducer of the lenticular gall, is regarded to be an inquiline. Pitydiplosis puerariae is distinguishable from the only known congener, the Nearctic Pitydiplosis packardi, by the male genitalia with entire aedeagus and with hypoproct that is as long as cerci and bilobed with a U‐shaped emargination. DNA sequencing data indicate the existence of three genetically different intraspecific groups: (i) “YNT‐montana group” induces galls on Pueraria montana on the Yaeyama Islands, Japan and in northern Taiwan; (ii) “CT‐montana group” on P. montana in central Taiwan; (iii) and “JCK‐lobata group” on Pueraria lobata in mainland China, South Korea and Japan north of Okinoerabu Island. A possible diversification scenario of the three groups is hypothesized based on DNA sequencing data and geohistorical information. A distribution gap of the gall midge on five islands between Tokunoshima and Ishigaki Islands, Japan was confirmed by intensive field surveys. Ecological traits and adult behavior of Pity. puerariae are also described. Its possibility as a potential biological control agent against P. lobata seems counter‐indicated.  相似文献   
107.
108.
In April 2009 two specimens of a terrestrial flatworm were collected from under a rock in an orchard at Ciutadella de Menorca on the easternmost Balearic island of Menorca (Spain). Their external morphology suggested that both specimens belonged to the invasive blue planarian Caenoplana coerulea, a species which is native to eastern Australia. Sequence data of a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) and of the entire 18S ribosomal RNA confirm its identification. This is one of the first records of the species in Europe where it has only been found in one locality in the United Kingdom, France and NE Spain.  相似文献   
109.
110.
Maemonstrilla gen. nov. , known exclusively from females, is proposed for Monstrilla longipes A. Scott, 1909, M. turgida A. Scott, 1909, and five new species from coral reef plankton in the Ryukyu Islands, Japan: Maemonstrilla hyottoko sp. nov. (type species), M. polka sp. nov. , M. spinicoxa sp. nov. , M. simplex sp. nov. and M. okame sp. nov. A syntype of M. turgida was examined, but the holotype of M. longipes is lost; the latter species, being similar to several of the new species, is regarded as unidentifiable, and the identity of specimens assigned to it by several authors is put in doubt. Until now, all known female monstrilloids have had posteriorly trailing ovigerous spines, but in Maemonstrilla gen. nov. these spines point anteriorly and hold the egg mass between the legs beneath the thorax. This is the first known instance of subthoracic brooding in a planktonic copepod; its functional significance is discussed, and brooding habits of non‐planktonic copepods are briefly reviewed. The intercoxal sclerites of legs 1–4 in Maemonstrilla gen. nov. are very wide, making room for the eggs. In all species except M. turgida comb. nov. , the inner seta of the proximal segment of each leg ramus is either absent or reduced to a nub; this may lessen interference of the egg mass with leg movement. All species have a uniramous leg 5 with two setae, except M. turgida comb. nov. (biramous with setae on both rami); M. turgida comb. nov. is evidently the sister‐group of its congeners, each sister‐group in the genus being defined by additional autapomorphies. Scanning electron micrographs of all the Ryukyuan species except M. simplex sp. nov. are provided; these constitute a preliminary survey of monstrilloid integumental organs and cuticular ornamentation. Among the unusual features are two lobes at the base of the coxa in legs 1–4 of M. polka sp. nov. and M. spinicoxa sp. nov. and two pairs of posterodorsal spine‐like scales on the first and second free pedigers of M. turgida comb. nov. Newly hatched nauplii of M. okame sp. nov. , examined by scanning electron microscopy, are generally similar to those of Monstrilla hamatapex Grygier & Ohtsuka, 1995, but with a different mandibular structure in which the distal hook and seta clearly represent the endopod, not enditic armament of the basis. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152 , 459–506.  相似文献   
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