Natural habitats uncovered? – Genetic structure of known and newly found localities of the endangered bitterling Pseudorhodeus tanago (Cyprinidae)

By

Saitoh, Kenji
Suzuki, Noriyasu
Ozaki, Masumi
Ishii, Kazuhiro
Sado, Tetsuya
Morosawa, Takahiro
Tsunagawa, Takatoshi
Tsuchiya, Masaru

Type

Article

Date of Publication

2017

Original Publication

Nature conservation

Volume

17

Pages

19-33

Subjects

Bottleneck , bucket biology , Conservation genetics , fish dumping , home aquarium , phylogeography , Poaching , satoyama , Tanakia tanago

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers 2012-

Identifiers

DOI: https://doi.org/10.3897/natureconservation.17.10939

 

Abstract

Overuse of natural resources by humans is a major threat to biodiversity. Overuse often involves species of economic or esthetic value, and fish are a typical example for a group that is exploited both for economic reasons (for human consumption) and for esthetic reasons (e.g. by aquarists). Pseudorhodeus tanago (Tanaka, 1909) (formerly known as Tanakia tanago) is a small colorful but legally protected (fishing, keeping and transfer are banned) bitterling fish distributed around Tokyo, Japan. Whereas it is critically endangered and more and more habitat loss has occurred, at least four stocks have been newly found during the last decade. To explore whether emergence of these newly found habitats is a consequence of incomplete survey, we genotyped mitochondrial cytochrome b sequence of P. tanago from 17 localities and an illegal home aquarium. Populations known by the past extensive survey (13 localities) showed geographically structured population genetic characteristics. Population-specific haplotypes were common indicating past divergence and bottleneck events. Four (north, {center + west}, south_1, south_2) or five (north, center, west, south_1, south_2) geographic groups were detectable as for these known localities. On the other hand, newly found stocks were polymorphic and showed identical haplotypes from distant known localities. If we assume historical basis of distribution and genetic characteristics of these newly found stocks, it must be a series of unlikely geological events and haplotype sorting. We discuss potential issues posed by these questionable stocks.