Venus (Journal of the Malacological Society of Japan)
Online ISSN : 2189-7697
Print ISSN : 1348-2955
ISSN-L : 1348-2955
Volume 67 , Issue 3-4
Showing 1-10 articles out of 10 articles from the selected issue
  • Yuko Fujita, Hiroto Matsumoto, Yoshihiro Fujiwara, Jun Hashimoto, Serg ...
    Type: Original Article
    2009 Volume 67 Issue 3-4 Pages 123-134
    Published: February 28, 2009
    Released: May 31, 2016
    We have investigated worldwide phylogenetic relationships of deep-sea Bathymodiolus mussels and their mytilid relatives by determining mitochondrial DNA sequences. We review herein their phylogenetic relationships and the evolutionary process deduced from studies of described and unidentified species collected recently from vents, seeps, sunken whale carcasses and wood. Phylogenetic analysis of the sequence data together with those from a database showed that the mytilid mussels were divided into six clusters and that the mussels in the subfamily Bathymodiolinae are split into four groups. Neither the subfamily Bathymodiolinae nor the genus Bathymodiolus were monophyletic, suggesting that it is necessary to reevaluate their classification. In the evolutionary process of the conventional Bathymodiolinae, the group including only Tamu fisheri split first, and the basal trichotomous split into the remaining three groups was followed by diversification of bathymodioline mussels in each group. The first group bifurcated into two subgroups, which include Bathymodiolus and Gigantidas species, respectively. The second group was subdivided into three subclusters containing Indo-West Pacific, Atlantic and eastern Pacific species respectively. The third group included two nominal species restricted to the western Pacific. Species obtained from sunken whale carcasses and wood took the outgroup position to the vent/seep mussels with only one exception, Adipicola crypta from whale carcasses. Modiolus modiolus from shallow water was positioned more distantly to the vent/seep mussels. The findings indicate an evolutionary transition from shallow water to vent/seep sites via whale carcass/wood sites, supporting the "Evolutionary stepping stone hypothesis".
    Download PDF (187K)
Original Articles
Short Notes