2013 Volume 3 Pages 29-38
To examine the phylogeography of the water scorpion, Nepa hoffmanni, a semi-endemic species of the Circum Ise-Bay area (CIBA) in Japan, we sequenced part of the mitochondrial DNA 16S rRNA and examined the genetic diversity along with the relationship between the polymorphisms and the surface geological features of the habitats. We confirmed that intraspecific variation of 16S rRNA was present in the CIBA with two different haplotype groups: 1) the South West-Mikawa group, which diverged first and was distributed only in the Ryoke metamorphic bedrock formed by uplifting due to activation of tectonic tilting of the Nobi Plain (early to mid Pliocene, 5.3-3 Ma), 2) the CIBA-Chita group, which is distributed across the entire CIBA, was composed of haplotypes that were genetically closely related and underwent simultaneous radiation later than did the other groups. It was supposed that geographical variation in the genetic structure of N. hoffmanni in the CIBA resulted from the activation of tectonic tilting of the Nobi Plain after the early Pliocene (5.3 Ma).
