2009年12月30日 星期三

以DNA條碼鑑識由8個地區輸入北美之近半數之珊瑚礁觀賞魚以作為未來觀賞魚撈捕永續經營之參考

[superlink: PLoS ONE]
文獻來源: Steinke D, Zemlak TS, Hebert PDN. 2009. Barcoding Nemo: DNA-Based Identifications for the Ornamental Fish Trade. PLoS ONE 4(7): e6300. doi:10.1371/journal.pone.0006300

Abstract
Background
Trade in ornamental fishes represents, by far, the largest route for the importation of exotic vertebrates. There is growing pressure to regulate this trade with the goal of ensuring that species are sustainably harvested and that their point of origin is accurately reported. One important element of such regulation involves easy access to specimen identifications, a task that is currently difficult for all but specialists because of the large number of species involved. The present study represents an important first step in making identifications more accessible by assembling a DNA barcode reference sequence library for nearly half of the ornamental fish species imported into North America.

Methodology/Principal Findings

Analysis of the cytochrome c oxidase subunit I (COI) gene from 391 species from 8 coral reef locations revealed that 98% of these species exhibit distinct barcode clusters, allowing their unambiguous identification. Most species showed little intra-specific variation (adjusted mean = 0.21%), but nine species included two or three lineages showing much more divergence (2.19–6.52%) and likely represent overlooked species complexes. By contrast, three genera contained a species pair or triad that lacked barcode divergence, cases that may reflect hybridization, young taxa or taxonomic over-splitting.

Conclusions/Significance

Although incomplete, this barcode library already provides a new species identification tool for the ornamental fish industry, opening a realm of applications linked to collection practices, regulatory control and conservation.