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論文(リポジトリ)

論文(リポジトリ)
Iwamoto, Kensuke ; Chang, Chin-Wei ; Imai, Hideyuki
出版情報: Biogeography : international journal of biogeography, phylogeny, taxonomy, ecology, biodiversity, evolution, and conservation biology.  22  pp.26-34,  2020-09-20.  Biogeographical Society of Japan — 日本生物地理学会
URL: http://hdl.handle.net/20.500.12000/46909
概要: Studies have suggested that fishes with broad distribution ranges, long pelagic duration, and great mobility in their ea rly life histories may have an advantage in their ability to return to their natal reef habitats. Siganus spinus is a siganid fish with a broad dispersal strategy, which may also exploit its great mobility to enhance self-recruitment. Variations in mitochondrial DNA sequences were analysed to estimate the genetic structure and demographic history of Siganus spinus in the West Pacific. In total, 446 nucleotide sequences, including the tRNAThr gene, the tRNAPro gene, and the first half of the control region, were analysed from 240 individuals sampled at five sites spanning the West Pacific Ocean; 37 haplotypes were identified. Our results showed significant geographic genetic structure as well as isolation by distance. Both neutrality tests and mismatch distribution indicated that the population expansion of S. spinus through the study area may have occurred in the late Quaternary. A dispersal strategy characterised by large juveniles and open-sea distribution may have contributed to a sudden population expansion after the last glacial period, along with an expansion of distribution.
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2.

論文(リポジトリ)

論文(リポジトリ)
Iwamoto, Kensuke ; Abdullah, Muhamad Fadry ; Chang, Chih-Wei ; Yoshino, Tetsuo ; Imai, Hideyuki
出版情報: Biogeography : international journal of biogeography, phylogeny, taxonomy, ecology, biodiversity, evolution, and conservation biology.  17  pp.61-85,  2015-09-20.  The Biogeographical Society of Japan — 日本生物地理学会
URL: http://hdl.handle.net/20.500.12000/37547
概要: A nucleotide sequence analysis of the mitochondrial DNA control region was conducted to reveal the genetic population st ructure and demographic history of the mottled spinefoot Siganus fuscescens (Houttuyn, 1782), and we discussed the taxonomic treatment of S. fuscescens and white-spotted spinefoot S. canaliculatus (Park, 1797) in terms of population genetics and morphological studies. Sequence analysis indicated that the haplotypes could be clearly divided into three lineages. Morphological analysis indicated no significant differences among measurements for the three genetically divergent lineages. We concluded that each lineage had once been isolated, and then former allopatric lineages may have resulted in the sympatric distribution of lineages due to secondary contact. Siganus fuscescens regards as valid species, and S. canaliculatus is a junior synonym of S. fuscescens.
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3.

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論文(リポジトリ)
アブドゥラ, ムハッマド ファドリー ; 井上, 博 ; 岩本, 健輔 ; 今井, 秀行 ; Abdullah, Muhamad Fadry ; Inoue, Hiroshi ; Iwamoto, Kensuke ; Imai, Hideyuki
出版情報: 沖縄生物学会誌.  48  pp.77-89,  2010-09-15.  沖縄生物学会
URL: http://hdl.handle.net/20.500.12000/37569
概要: The western form of the spotted-legged spiny lobster Panulirus lonipes longipes (A. Milne-Edwards,1 868),collected from Okinawajima Island,Okinawa Islands,]apan,i s reported here. This report represents the second record of the species from Japan. Based on the specimens examined in this study, we propose a new Japanese\nname “Nettai-iseebi" for P. longipes longipes. Random amplified polymorphic DNA(RAPD) analysis was used to examine phylogenetic relationships within and between 12 Indo-Pacific lobster species. In total,20 RAPD primers were screened for their use in identifying genetic polymorphism in Panulirus. Thirteen positive primers that gave highly reproducible RAPD profiles were selected for the analysis of the genetic relationships of Panulirus. The mean genetic similarity index (SI) among species measured by band sharing in all comparisons was 0.2673土0.0090. The highest SI value of their RAPD bands was 0.7698, while the lowest was 0.0931. Dendograms were constructed from the pair-wise comparisons among all species using pooled data from all positive primers. The similarity within first cluster of P. longipes complex deserves considerable attention. This finding, although restricted to one subspecies, appears to indicate that there is a low degree of genetic similarity between P. longipes longipes and P. longiρes bisρinosus with similarity value between 27 and 46%. Such low similarity indexes are more commonly observed between different species than within one species. Clusters generated from neighbor-joining and unweighted pair group method with arithmetic mean (UPGMA) analyses yielded trees with different topologies,indicating poor resolution within the lineage, although the clade of the P. longipes complex was clearly indicated.
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