Molecular phylogeny and morphologic data of strains of the genus <em>Coelastrella</em> (Chlorophyta, Scenedesmaceae) from a tropical region in North America (Yucatan Peninsula)

Abstract

Background: Scenedesmaceae family exhibits great morphological variability. High phenotypic plasticity and the presence of cryptic species have resulted in taxonomic re-assignments of Scenedesmaceae members. Study strains: Strains CORE-1, CORE-2 and CORE-3 were characterized. Study site: Yucatan Peninsula Methods: Morphological analyses were executed by optical and scanning electron microscopy. Phylogenetic relationships were examined by ITS-2 and ITS1-5.8S-ITS2 rDNA regions. Results: Optical and scanning electron microscopy analyses indicated spherical to ellipsoidal cells and autospore formation correspond to members of the family Scenedesmaceae, as well as observable pyrenoid starch plates. Detailed morphology analysis indicated that CORE-1 had visible granulations dispersed on the cell wall, suggesting identity with Verrucodesmus verrucosus. However CORE-1 did not show genetic relations with this species, and was instead clustered close to the genus Coelastrella. CORE-2 did not show any particular structure or ornamentation, but it did show genetic relations with Coelastrella with good support. CORE-3 showed meridional ribs from end to end, one of them forked and well pronounced, and orange cells in older cultures characteristic of Coelastrella specimens. Phylogenetic trees of ITS-2 and ITS1-5.8S-ITS2 rDNA sequences indicated with good support that all strains were related to the genus Coelastrella despite their morphologic differences. Conclusions: This study reports freshwater Coelastrella strains from a tropical region in North America (Yucatan Peninsula) for the first time. The results contribute to knowledge of for the first time. The results contribute to knowledge of Coelastrella species, and the fact that they do not always show structures that are useful for taxonomic assignment, probably as a result of phenotypic plasticity.

Novel microalgae strains from selected lower Himalayan aquatic habitats as potential sources of green products

“…Scenedesmaceae–a family of closely-related, green and coccoid microalgae–is famous for its ubiquity, resilience as well as unmatched ability to colonize extreme environments [ 32 ]. We couldn’t lay on our hands on the most recent estimate, but according to an earlier investigation [ 33 ] there were up to 54 different genera within this diverse family.…”

Revision of Coelastrella (Scenedesmaceae, Chlorophyta) and first register of this green coccoid microalga for continental Norway

“…Members of the subfamily Coelastroideae have been previously placed in the families Oocystaceae, Chlorellaceae, and Scotielloideae based on shape, reproduction, cell wall morphology and composition (Kalina and PunČochářová 1987 ), until phylogenetic molecular studies were applied. Nowadays, DNA amplification and sequencing of the 18S rDNA and internal transcribed spacer (ITS) studies placed Coelastroideae within the family Scenedesmaceae, order Sphaeropleales (Hanagata 1998 , 2001 ; Hegewald and Hanagata 2000 , 2002 ; Hegewald et al 2010 ; Kaufnerová and Eliáš 2013 ; Lee et al 2016 ; Ancona-Canché et al 2017 ). According to AlgaeBase (Guiry and Guiry 2020 ), the subfamily Coelastroideae comprises seven genera: Coelastrella Chodat 1922 (16 species flagged as accepted taxonomically), Scotiellopsis Vinatzer 1975 (1 sp.…”

DNA barcoding approach to characterize microalgae isolated from freshwater systems in Ecuador

“…This rate increased to 52% when the rbcL BLAST results were taken into account. Several studies highlight the necessity of using several barcodes to properly identify strains at the species level, especially in the Scenedesmaceae [65][66][67] and Chloraellaceae families [68]. The use of rbcL is not very common in Chlorophyta microalga phylogenetics, but it was useful for characterizing our collection, despite the rate of unsuccessful amplifications reported by others [31,38].…”