Premium
SYSTEMATICS OF PRASIOLA AND PHYLOGENETIC POSITIONING OF THE PRASIOLALES (CHLOROPHYTA)
Publication year - 2001
Publication title -
journal of phycology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.85
H-Index - 127
eISSN - 1529-8817
pISSN - 0022-3646
DOI - 10.1111/j.1529-8817.2001.jpy37303-115.x
Subject(s) - biology , herbarium , upgma , systematics , phylogenetic tree , maximum parsimony , botany , genus , subgenus , molecular phylogenetics , clade , range (aeronautics) , evolutionary biology , taxonomy (biology) , genetic variation , genetics , gene , materials science , composite material
Sherwood, A. R. 1 & Sheath, R. G. 21 Present address: Department of Botany, 3190 Maile Way, University of Hawaii, Honolulu, HI 96822 U.S.A. 2 Department of Botany and Dean's Office, University of Guelph, Guelph, ON N1G 2W1 Canada The systematics of the green algal genus Prasiola was investigated through a combination of morphometric and molecular analyses, and the phylogenetic position of the order Prasiolales was re‐examined with molecular tools. Thirty‐six herbarium sheets of Prasiola as well as 39 field collections and 12 type specimens were measured for several cellular and thallus characters. Means of each character were used in both cluster (UPGMA algorithm) and principal components analyses (PCA) to examine relationships among collections. Significant differences among means from the resulting groups were tested using one‐way analysis of variance (ANOVA; p<0.05). Both cluster analysis and PCA resolved five groups of specimens, of which four groups were associated with at least one type specimen. Parsimony and distance analyses of the first half of the 18S rRNA gene support the Prasiolales as being a sister clade to the Trebouxiophyceae. Uncorrected sequence divergence values within the Prasiolales range from 0‐1.7%, and within Prasiola range from 0‐1.4%. Analyses of the rbcL gene were not well resolved at the ordinal level, but revealed some interesting trends within and among the genera, such as sequence identity among several morphologically distinct marine species of Prasiola, and large sequence divergence values between marine and freshwater Prasiola. Inclusion of representatives of the other members of the Prasiolales (Rosenvingiella, Prasiococcus and Prasiolopsis) confirmed that the Prasiolales is a monophyletic group.