Biogeographical analyses of Batrachospermum helminthosum (Batrachospermales, Rhodophyta) in North America using molecular and morphological data
2001
Vis, Morgan L. | Miller, Emily J. | Hall, Melissa M.
Twelve samples of Batrachospermum helminthosum were collected from stream sites throughout the species' range in eastern North America as follows: three samples from Ohio, two from Michigan, and one each from Indiana, Tennessee, Louisiana, North Carolina, Connecticut, Rhode Island and Massachusetts. The plastid-encoded Rubisco large subunit gene (rbcL) and the nuclear region of ITS1-5.8S rDNA-ITS2 were sequenced from each individual. Analysis of the rbcL sequence revealed five genotypes among the samples, with one genotype represented by seven samples. The ITS data showed unique sequences for all samples, except for one from Ohio and the North Carolina sample, which were identical. Parsimony, distance and maximum-likelihood analyses yielded similar results, showing two clades of samples. One clade contained the majority of samples and the other comprised the Tennessee and Michigan samples. The phylogeography of the species appears to be complex, with samples from distant locations being genetically similar. Analysis of morphometric characteristics showed the species to be morphologically plastic across its range.
显示更多 [+] 显示较少 [-]