caa a22 4500 445845821 CHVBK 20180317145358.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s10709-012-9638-9 doi (NATIONALLICENCE)springer-10.1007/s10709-012-9638-9 Mitochondrial and nuclear DNA analysis revealed a cryptic species and genetic introgression in Littorina sitkana (Mollusca, Gastropoda) [Elektronische Daten] [Noriko Azuma, Tomoyasu Yamazaki, Susumu Chiba] We investigated mitochondrial and nuclear DNA genotypes in nominal Littorina sitkana samples from 2 localities in Eastern Hokkaido, northern Japan. Our results indicated the existence of cryptic species. In the analysis of partial mitochondrial Cytchrome b gene sequences, haplotypes of L. sitkana samples were monophyletic in a phylogenetic tree with orthologous sequences from other Littorina species, but were apparently separated in 2 clades. One included typical L. sitkana (CBa clade) samples, which formed a clade with an allopatric species, L. horikawai. The other, CBb, was independent from CBa and L. horikawai. Haplotypes of the mitochondrial 16S rRNA gene also separated into 2 clades. We additionally examined intron sequence of the heat shock cognate 70 (HSC70) nuclear gene and identified 17 haplotypes. These were also separated into 2 clades, HSCa and HSCb. Among the examined Hokkaido samples, 60% of individuals were heterozygotes. However, each heterozygote consisted of haplotypes from the same clade, HSCa or HSCb, and no admixture of HSCa and HSCb haplotypes was observed. These results indicate reproductive isolation between the 2 clades. Among the genotyped Hokkaido samples, 93% of individuals had CBa+HSCa or CBb+HSCb genotypes, and 7% had CBb+HSCa genotypes. The discrepancy between the mtDNA and nuclear DNA haplotypes in a few individuals may have been caused by genetic introgression due to past hybridization. Springer Science+Business Media B.V., 2012 Periwinkle nationallicence Speciation nationallicence Reproductive isolation nationallicence Cytb nationallicence 16S nationallicence HSC70 nationallicence Azuma Noriko Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan aut Yamazaki Tomoyasu Shellfish Museum of Rankoshi, Rankoshi, Hokkaido, Japan aut Chiba Susumu Faculty of Bioindustry, Tokyo University of Agriculture, Abashiri, Hokkaido, Japan aut Genetica Springer Netherlands 139/11-12(2011-12-01), 1399-1408 0016-6707 139:11-12<1399 2011 139 10709 https://doi.org/10.1007/s10709-012-9638-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10709-012-9638-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Azuma Noriko Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan aut NATIONALLICENCE 700 1- Yamazaki Tomoyasu Shellfish Museum of Rankoshi, Rankoshi, Hokkaido, Japan aut NATIONALLICENCE 700 1- Chiba Susumu Faculty of Bioindustry, Tokyo University of Agriculture, Abashiri, Hokkaido, Japan aut NATIONALLICENCE 773 0- Genetica Springer Netherlands 139/11-12(2011-12-01), 1399-1408 0016-6707 139:11-12<1399 2011 139 10709 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer