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101.
The temporal and spatial origins and evolution of the genus Eranthis have not been previously studied. We investigated the speciation and establishment histories of four Eranthis species: Eranthis byunsanensis, E. pungdoensis, E. stellata, and E. pinnatifida. The sampling localities were Korea, Japan, Jilin in China, and the area near Vladivostok in Primorskiy, Russia. We used 12 chloroplast microsatellite loci (n = 935 individuals) and two chloroplast noncoding regions (rpl16 intron, petLpsbE intergenic spacer; n = 33 individuals). The genetic diversity, genetic structure, phylogenetic relationships of the four species were analyzed, and their ancestral areas were reconstructed. The high genetic diversity of the Jeju island population of E. byunsanensis and Russian populations of E. stellata indicated these species’ northward and southward dispersal, respectively. The genetic structure analyses suggest that the populations in these four species have limited geographical structure, except for the Chinese E. stellata population (SCP). The phylogenetic analyses suggest that E. byunsanensis and E. pinnatifida are sister species and that Chinese SCP may not belong to E. stellata. The ancestral area reconstruction revealed that the most recent common ancestor of the four species existed in the current Chinese habitat of E. stellata. This study shows that E. byunsanensis and E. pinnatifida originated from a southern Eranthis species and speciated into their current forms near Jeju island and near western regions of Japan, respectively, during the Miocene. E. stellata may have dispersed southward on and near the Korean peninsula, though its specific origin remains unclear. Interestingly, the Chinese E. stellata population SCP suggests that the Chinese population might be most ancient among all the four Eranthis species. E. pungdoensis may have allopatrically speciated from E. byunsanensis during the Holocene. The Korean peninsula and the surrounding areas can be considered interesting regions which provide the opportunity to observe both northern‐ and southern‐sourced Eranthis species.  相似文献   
102.
103.
Eight temperate seagrass species (five in the genus Zostera, two in the genus Phyllospadix, and Ruppia maritima) have been previously reported in coastal waters off the Korean peninsula, which lies between 33°N and 43°N. Recently, a species of Halophila, a genus which occurs predominantly in tropical and subtropical areas, has been observed on the southern coast of Korea for the first time. The species was identified as Halophila nipponica. H. nipponica is distributed in warm temperate regions of Japan influenced by the warm Tsushima Current and was previously unknown outside the Japanese archipelago. Thus, we are able to report a range extension into Korea. The Korean Halophila meadow that we observed covered an area of about 2.1 ha, with average shoot density of about 1300 m−2. We measured morphological features of vegetative and reproductive organs between June and September 2007. Morphological and reproductive features of the Halophila species in Korea were similar to those of the species in Japan. Increased water temperature in the coastal waters of Korea may at least partially account for the persistence of this new population.  相似文献   
104.
Dmitar Lakušić 《Biologia》2008,63(5):631-636
The south-European Cardamine plumieri Vill. (sect. Pteroneurum subsect. Cryptopterum) is confirmed for the Flora of Serbia. Several populations were discovered in the central and western part of country, exclusively on the serpentine bedrocks. Morphological, chorological and ecological characteristics of C. plumieri was studied.  相似文献   
105.
A phytosociological study was carried out along a 450 kmtransect in tropical southeastern Mexico in order to identify plantcommunities.Five major plant communities were distinguished and described:Those communities reflect preference of different environmentalfactorssuch as soils, precipitation and local relief. Further, the major threats(hurricanes, fires, agriculture) to the vegetation of the study areaare discussed.  相似文献   
106.
Human population expansion has promoted contact between wildlife and domestic animals with severe ecological consequences, such as anthropogenic hybridization. In Portugal, Iberian wolf (Canis lupus signatus) populations are considered “Endangered” and co-habit with humans so the risks of hybridization with free-ranging dogs, and livestock depredation can be particularly high. Our aim was to report the occurrence of wolf-dog hybridization in an endangered Iberian wolf sub-population, located in the south of the Douro river, Portugal. We used mitochondrial DNA and microsatellite data to investigate putative hybrids between Iberian wolves and dogs. Here, we report for the first time a wolf-dog hybrid located in the south of the Douro river. This is the second hybrid found in Portugal, and even if hybridization cases are still considered rare, they can be particularly problematic in isolated, fragmented and endangered populations, such as the one studied here. Appropriate management and conservation measures are recommended.  相似文献   
107.
A tyrannosauroid dinosaur from the Upper Jurassic of Portugal   总被引:2,自引:0,他引:2  
Fragmentary theropod remains from the Upper Jurassic (Kimmeridgian) of Guimarota, Portugal, represent a new taxon of theropod dinosaurs, Aviatyrannis jurassica gen. et sp. nov. Together with Stokesosaurus from the Morrison Formation of North America, Aviatyrannis represents the oldest known tyrannosauroid, indicating that tyrannosauroid origins may be found in the Middle–Late Jurassic of Europe/North America. Furthermore, current evidence suggests that early tyrannosaurs were rather small animals, which is in general accordance with their origin amongst the generally rather small coelurosaurs.  相似文献   
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