Phylogeographic patterns indicate cryptic species diversity in the red algae Gloiopeltis furcata (Gigartinales) in the northern Pacific region

Abstract

Recent molecular analyses have demonstrated that many widespread species consist of species complexes with high genetic diversity. The red algae Gloiopeltis furcata is a suitable candidate species for studying cryptic diversity because of its broad distribution in the northern Pacific Ocean. To examine the genetic diversity within the species in realtion to current distribution, we analyzed a total of 108 COI-5P and 110 rbcL sequences from G. furcata specimens collected in Korea, Japan, Russia and Canada. Phylogenetic trees and haplotype analyses of COI-5P and rbcL revealed high cryptic diversity comprising five distinct genetic groups within G. furcata. The five genetic groups were identified as 1) Korea/Japan/Canada/Russia population, 2 & 3) Korea/Japan population, 4) Japanese population, and 5) Korean population. Our results show the highly complicated genetic structure in specimens from Korea and Japan and extremely low haplotype diversity in Canada compared to the western Pacific. The presence of disconnected groups in G. furcata represents several novel species, highlighting the importance of phylogeographic approaches for discovering cryptic algal biodiversity.ts broad distribution in the northern Pacific Ocean. To examine the genetic diversity within the species in realtion to current distribution, we analyzed a total of 108 COI-5P and 110 rbcL sequences from G. furcata specimens collected in Korea, Japan, Russia and Canada. Phylogenetic trees and haplotype analyses of COI-5P and rbcL revealed high cryptic diversity comprising five distinct genetic groups within G. furcata. The five genetic groups were identified as 1) Korea/Japan/Canada/Russia population, 2 & 3) Korea/Japan population, 4) Japanese population, and 5) Korean population. Our results show the highly complicated genetic structure in specimens from Korea and Japan and extremely low haplotype diversity in Canada compared to the western Pacific. The presence of disconnected groups in G. furcata represents several novel species, highlighting the importance of phylogeographic approaches for discovering cryptic algal biodiversity.