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1.
A morphometric and electrophoretic survey was conducted to examine taxonomic relationships among eight population samples of the Rana narina complex from the Ryukyu Archipelago of Japan and Taiwan. Five discrete morphotypes are differentiated, and these showed considerable genetic differentiation from each other. From the available information, each of the five morphotypes is judged to represent a species, and three are described as new. Rana utsunomiyaorum sp. nov. and R. supranarina sp. nov. are sympatric in Ishigakijima and Iriomotejima islands of the Yaeyama Group, and differ from the other members by having a shorter hindlimb. Rana utsunomiyaorum is the smallest in the complex, while R. supranarina is the largest. Rana amamiensis sp. nov . occurs on Amamioshima and Tokunoshima islands of the Amami Group and, like R. narina from Okinawajima of the Okinawa Group, has a long hindlimb; it differs from the latter species by having a larger body and relatively small tympanum. These two species differ from R. swinhoana from Taiwan by having a narrower disk on the third finger. A key to known species of the complex is given. Further, syslematics of the R. narina complex within Rana , body size in the two sympatric species, and sexual dimorphism found in this complex are discussed.  相似文献   
2.
Wildlife populations in semi-arid regions are increasingly challenged by human activities and dependent on the connectivity of riparian corridors for access to surface water. The Madrean Archipelago is a biodiversity hotspot along the arid United States–Mexico borderlands that support both Neotropical and Nearctic wildlife. Infrastructure development (e.g., the border wall and the expansion of Mexican Federal Highway 2) in this region inhibits wildlife movement along the transnational mountain archipelago by disconnecting habitat. To explore the relationship between habitat variables and mammal use of riparian corridors in northern Sonora, Mexico, we collected data from 19 motion-sensitive cameras between October 2018 and April 2019 and used single-season occupancy models and Royle-Nichols abundance estimation models to analyze our data. We recorded 21 species of mammals, including the first sighting of jaguar (Panthera onca) in this region in 25 years. River characteristics (distance from river, riparian corridor width, water availability), remoteness (distance from highway, productivity, elevation), and topographic variety (vertical elevation difference) influenced patterns of occupancy probability and estimated abundance of mammals >1 kg, but the strength and direction of these relationships varied by species. Additionally, intermittently wet desert washes were comparable in species richness to the perennial system. These results highlight the importance of examining physical and biological aspects of habitat. This is especially true when identifying corridors where mitigation structures should be placed to improve wildlife connectivity in biodiversity hotspots like the Madrean Archipelago and semi-arid ecosystems worldwide.  相似文献   
3.
Aim This study aims to explain the patterns of species richness and nestedness of a terrestrial bird community in a poorly studied region. Location Twenty‐six islands in the Dahlak Archipelago, Southern Red Sea, Eritrea. Methods The islands and five mainland areas were censused in summer 1999 and winter 2001. To study the importance of island size, isolation from the mainland and inter‐island distance, I used constrained null models for the nestedness temperature calculator and a cluster analysis. Results Species richness depended on island area and isolation from the mainland. Nestedness was detected, even when passive sampling was accounted for. The nested rank of islands was correlated with area and species richness, but not with isolation. Idiosyncrasies appeared among species‐poor and species‐rich islands, and among common and rare species. Cluster analysis showed differences among species‐rich islands, close similarity among species‐poor and idiosyncratic islands, and that the compositional similarity among islands decreased with increasing inter‐island distance. Thus, faunas of species‐poor, smaller islands were more likely to be subsets of faunas of species‐rich, larger islands if the distance between the islands was short. Main conclusions Species richness and nestedness were related to island area, and nestedness also to inter‐island distances but not to isolation from the mainland. Thus, nestedness and species richness are not affected in the same way by area and distance. Moreover, idiosyncrasies may have been the outcome of species distributions among islands being influenced also by non‐nested distributions of habitats, inter–specific interactions, and differences in species distributions across the mainland. Idiosyncrasies in nested patterns may be as important as the nested pattern itself for conservation – and conservation strategies based on nestedness and strong area effects (e.g. protection of only larger islands) may fail to preserve idiosyncratic species/habitats.  相似文献   
4.
The skulls of 387 shrews of the genus Crocidura sampled in peninsular Malaysia, Sumatra, Borneo, Java and Sulawesi were submitted to principal component and stepwise discriminant analyses. These analyses helped to delineate morphological taxa in this species-rich genus of mammals. Most morphologic groups could be attributed to described species, except one taxon from Sumatra and one from Sulawesi, which are described and named as new. Most of the 21 species recognized in this paper are endemic to one major island. Although Sulawesi has never been connected to the mainland, it supports at least six species, followed by Sumatra (5–6 species), Java and the Malay Peninsula (4 spp) and Borneo (3 spp). C. monticola is apparently the only widespread species whose distribution range covers the entire Malay Archipelago except the Philippines and Sulawesi. In contrast, the continental C. fuliginosa enters only marginally into the Sunda Shelf: its southernmost record is on the Malay Peninsula. This interpretation is completely different from the classical view that C. fuliginosa is a cosmopolitan species occupying the whole of Southeast Asia. Identification keys, tables of measurements and discriminant functions provided in this work may aid in identification of the various species and subspecies of Crocidura living in the Malaya Archipelago.  相似文献   
5.
Detailed life-history observations of Dermatolepis dermatolepis are given, including the location, size and timing of a probable spawning aggregation. These observations emphasize the general rarity of the species and the importance of no-take reserves in the management of offshore islands.  相似文献   
6.
Genus Rusa, belonging to the deer family Cervidae is native to the Indo-Malaya Archipelago (IMA). However, detailed information on the Rusa genus in the IMA is limited. This review provides comprehensive information on the Rusa genus in the IMA including, threats and conservation efforts. There are four species of deer in Rusa genus, which is Sambar deer (Rusa unicolor), Javan deer (Rusa timorensis), Visayan spotted deer (Rusa alfredi) and Philippine deer (Rusa marianna). Despite their wide distribution in the South Asian and Southeast Asian regions, they are under serious threats. Some conservation efforts that are being done to protect and conserve them among others are; (1) facilities protection, (2) habitat enrichment programme, (3) Ex-situ conservation, (4) legislations, and (5) captive breeding. Conservation through genetics is also an important step in conserving these species. Recommendations for conservation of the genus are also discussed; 1. maintenance of ecosystem. 2. more effective monitoring system on the existing protected area. 3. ex-situ conservation, and 4. habitat monitoring.  相似文献   
7.
Abstract

Benthic marine flora of Tuscan Archipelago has been studied. Several samples were collected along five islands and some rocks. This paper is a compendium of new and already published data, in which 267 species, varieties, forms and stadia of algae and seagrasses are listed: 5 Bangiophyceae, 182 Florideophyceae, 45 Phaeophyceae, 6 Chlorophyceae, 28 Bryopsidophyceae, 1 Angiospermae.  相似文献   
8.
The Indo‐Australian Archipelago (IAA) is the richest area of biodiversity in the marine realm, yet the processes that generate and maintain this diversity are poorly understood and have hardly been studied in the mangrove biotope. Cerithidea is a genus of marine and brackish‐water snails restricted to mangrove habitats in the Indo‐West Pacific, and its species are believed to have a short pelagic larval life. Using molecular and morphological techniques, we demonstrate the existence of 15 species, reconstruct their phylogeny and plot their geographical ranges. Sister species show a pattern of narrowly allopatric ranges across the IAA, with overlap only between clades that show evidence of ecological differentiation. These allopatric mosaic distributions suggest that speciation may have been driven by isolation during low sea‐level stands, during episodes preceding the Plio‐Pleistocene glaciations. The Makassar Strait forms a biogeographical barrier hindering eastward dispersal, corresponding to part of Wallace's Line in the terrestrial realm. Areas of maximum diversity of mangrove plants and their associated molluscs do not coincide closely. © 2013 The Natural History Museum. Biological Journal of the Linnean Society © 2013 The Linnean Society of London, 2013, 110 , 564–580.  相似文献   
9.
The East Asian giant water bug species Appasus japonicus Vuillefroy and Appasus major Esaki are aquatic hemipteran insects whose ranges overlap, particularly in the Japanese Archipelago and on the Korean Peninsula. In rare cases, the two species co‐occur. Furthermore, they are very similar ecologically and also morphologically, making their identification extremely difficult, and the possibility of hybridization has also been suggested. In the present study, we re‐examined their taxonomic validity, and the characteristics useful for identifying them. To re‐examine the morphological traits useful for distinguishing these two species, 222 specimens of A. japonicus collected from Japan, Korea, and China, and 132 specimens of A. major from Japan and Korea, were examined. We also performed molecular phylogenetic analyses based on the mitochondrial DNA 16S rRNA and cytochrome oxidase subunit I (COI) regions and the nuclear DNA Histone 3 region. Although the two species are very similar ecologically and also morphologically, they showed significant genetic differentiation. Thus, there is likely some form of reproductive isolation acting between them. Major morphological characteristics overlap extensively between A. japonicus and A. major, and no particular trait was identified as being effective for differentiating these species. All the morphological characteristics examined overlapped between A. japonicus and A. major. However, a principal component analysis based on all of the morphological characteristics revealed that, despite the overlap between these species, it was possible to morphologically distinguish them. Therefore, a more accurate identification becomes possible using multiple characteristics rather than a single characteristic. The male genital paralobes, evaluated as the most useful morphological characteristic, was effective with 100% probability for the Japanese Appasus species. However, for the Asian (i.e. Korean) specimens, this characteristic was not useful. On the other hand, the results of molecular phylogenetic analyses based on the mitochondrial DNA 16S rRNA and COI regions and the nuclear DNA Histone 3 region clearly showed significant genetic differentiation between the two species. Notably, the results for the mitochondrial COI region strongly supported the independence of each monophyletic group (i.e. validity of each species). Therefore, DNA barcoding based on the mitochondrial DNA COI region is also considered useful for the identification of A. japonicus and A. major. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 615–643.  相似文献   
10.
Arabis serrata (Brassicaceae), a perennial plant widely distributed along the Japanese Archipelago, occurs in various habitats: for example, limestone zones, serpentine barrens, volcanic soils, and roadsides. It likely survived by adapting to its surrounding environment, resulting in great morphological and ecological variation. In this study, we performed a phylogeographic analysis to examine past changes in the distribution of A. serrata following climate oscillations during the Pleistocene. To cover most of A. serrata's range, leaves were collected from eight to ten individuals randomly selected from each of 37 populations in the Japanese Archipelago. Two chloroplast noncoding regions of the samples were amplified and sequenced: trnT(GGU)‐psbD and trnH(GUG)‐psbA spacers. Twenty‐five haplotypes were detected and distinguished by 31 substitutions. Four main haplotypes were observed in many populations distributed throughout the Japanese Archipelago. According to the genetic boundaries detected using the Monmonier algorithm, A. serrata is clustered into four groups, each including several populations: Hokkaido Island, northern mainland Honshu, central Japan, and western Japan. The boundaries, however, were not robust because all genetic parameters did not support the differentiation among groups. These results indicate the absence of an obvious geographic structure in the distribution of A. serrata, suggesting that this species has experienced a rapid range expansion in postglacial times.  相似文献   
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