Molecular phylogeny of butterflies Parnassius glacialis and P. stubbendorfii at various localities in East Asia.

The phylogeny of butterflies, Parnassius stubbendorfii and P. glacialis, collected at various localities in the Japan archipelago and the eastern part of the Asian continent was analyzed using mitochondrial DNA sequences coding for NADH dehydrogenase subunit 5 (805 bp). The molecular phylogenetic trees revealed that P. glacialis and P. stubbendorfii diverged from a common ancestor, and then the populations inhabiting the Japan archipelago and the Asian continent diverged in each species. The reliability of these divergences was supported by high bootstrap values. The divergences within the Japan archipelago and within the Asian continent in each species were unclear because of low bootstrap values. The genetic distance and a rough time-estimation in the UPGMA tree suggest that the both populations of P. glacialis and P. stubbendorfii may have been isolated in the Japan archipelago at the early time (about 1.7-2.0 Mya) of the glacial period in the Pleistocene. The genetic distance between the Japanese and the continental subspecies may be large enough that they can be classified as different species, in comparison with the genetic distances among some other parnassian species.

[Study of two species of mussels, Mytilus trossulus and Mytilus galloprovincialis (Bivalvia, Mytilidae) and their hybrids, using PCR markers, in Peter the Great Bay of the Sea of Japan]. / Issledovanie dvukh vidov midiius trossulus i Mytilus galloprovincialis (Bivalvia, Mytilidae) i ikh gibridov v zalive Petra Velikovo Iaponskogo Moria s pomoshch'iu PTsR-markerov.

Bivalve mollusks of the genus Mytilus (M. trossulus and M. galloprovincialis) occurring in Peter the Great Bay of the Sea of Japan were first studied in Russia. A region of nonrepetitive sequences of the gene encoding the polyphenolic adhesive protein bissus was used as a species-specific genetic marker. After amplification using specific primers, a 126-bp fragment was found to amplify in all representatives of M. galloprovincialis collected from driftwood in the gulf Posset (the southwestern part of Peter the Great Bay). M. trossulus specimens from the same region were shown to have a 168-bp fragment. In Vostok Gulf (the eastern part of Peter the Great Bay), both artificially grown mussels and those from natural habitats contained a 168-bp fragment or two fragments (126- and 168-bp) that corresponded to a hybrid form between the above species. The possibility of using this genetic marker to identify closely related Mytilus strains and their hybrids in similar habitats, near the Primorye coast in particular, was demonstrated. The presence of approximately 9% of hybrid specimens confirms that a zone of hybridization between M. trossulus and M. galloprovincialis may exist in this region.

[Genetic connections between some species of Mytilidae (Mollusca: Bivalvia) from the northern part of the Pacific Ocean]. / Geneticheskie sviazi mezhdu nekotorymi vidami Mytilidae (Mollusca: Bivalvia) severnoi chasti tikhogo okeana.

In 1978 and 1999, seven and eight species of Mytilidae (Mollusca: Bivalvia) were analyzed using gel electrophoresis. Mean heterozygosity per individual (Hobs and Hexp) and genetic distances (Rogers' DR, Nei's DN, and others) were estimated for 21 and 24 allozyme loci. Mytilus modiolus had the highest variation among the species examined. Genetic distances were lowest for the M. trossulus-M. galloprovincialis species pair: DR = 0.147, DN = 0.078. Overall, five species of the genera Mytilus and Crenomytilus were genetically closer to each other (DR = 0.147, DN = 0.078) than to the remaining three species of this group (DR = 0.807, DN = 2.243). The relationships among the species were examined using cluster analysis and parsimony methods. The densest clusters in the dendrograms consisted of (1) M. trossulus and M. galloprovincialis and (2) M. coruscus, M. californianus, and M. grayanus. These two clusters form a larger cluster (3), which comprises all representatives of the nominal genus Mutilus and C. grayanus. The Mytilus-Crenomytilus cluster is consecutively joined by Adula falcatoides, Mytilus modiolus, and Septifer keenae. According to Nei's genetic distances DN, the time of divergence between M. trossulus and M. galloprovincialis is 0.8-1.6 Myr; between M. californianus and C. grayanus, it is approximately 9 Myr; and between M. coruscus and the latter pair, it is 13 Myr before present. Two representatives of the Mytilus ex gr. edulis complex diverged from the Mytilus-Crenomytilus group of large-size Pacific species about 20 Myr ago. These results are in good agreement with paleontological data and indicate a relatively recent origin of the Mytilus ex gr. edulis complex. The results obtained can be used in systematics and phylogeny of modern Mytilidae.