Y. Arai, T. Saruwatari, T. Kikkou, K. Sugahara, Y. Sato, S. Imada, Y. Katsuki, H. Kashiwa, C. Yokoyama, K. Iuchi, H. Hisatomi
Published: October 30, 2020
Genet. Mol. Res. 19(4): GMR18663
DOI: https://doi.org/10.4238/gmr18663

Cite this Article:
Y. Arai, T. Saruwatari, T. Kikkou, K. Sugahara, Y. Sato, S. Imada, Y. Katsuki, H. Kashiwa, C. Yokoyama, K. Iuchi, H. Hisatomi (2020). Molecular phylogeny of the white-spotted charr, Salvelinus leucomaenis from Japan and the position of the S. l. japonicus morphotype (nagaremon charr), demonstrating teleost diversification in an archipelago. Genet. Mol. Res. 19(4): GMR18663. https://doi.org/10.4238/gmr18663

About the Authors
Y. Arai, T. Saruwatari, T. Kikkou, K. Sugahara, Y. Sato, S. Imada, Y. Katsuki, H. Kashiwa, C. Yokoyama, K. Iuchi, H. Hisatomi
Corresponding Author: H. Hisatomi
Email: hisatomi@st.seikei.ac.jp

ABSTRACT

Four subspecies of white-spotted charr (Salvelinus leucomaenis) are known from the Japanese archipelago; S. l. imbrius, S. l. japonicus, S. l. leucomaenis, and S. l. pluvius. All four subspecies are popular as fisheries resources as well as targets of recreational sports fishing. Japanese S. leucomaenis showcase a unique example of diversification of teleosts inhabiting mountainous streams in a limited geographic range such as an archipelago in the Far East, worthy of detailed study. The Japanese endemic subspecies S. l. japonicus are further divided into two morphotypes, a typical type and a morphotype known as the Nagaremon char. We extracted complete mtDNA sequences of the four Japanese S. leucomaenis subspecies as well as that of the S. l. japonicus nagaremon morphotype. The mtDNA sequence of S. l. leucomaenis was 16,655 bp in length, whereas the typical type of S. l. japonicus had a sequence length of 16,654 bp and the nagaremon morphotype had 16,653 bp. There were one or two nucleotide deletions in the D-loop region of S. l. japonicus compared with the other S. leucomaenis subspecies. A phylogenetic tree showed that the typical morphotype of S. l. japonicus was the most basal subspecies, followed by S. l. pluvius. S. l. imbrius and the nagaremon morphotype, which formed a clade followed by S. l. leucomaenis. Comparison of whole mtDNA sequences among the four subspecies of S. leucomaenis revealed that the S. l. japonicus morphotype was most closely related to S. l. imbrius.

Key words: Mitochondrial DNA, Nagaremon charr, Salvelinus leucomaenis.