Cyanomargarita gen. nov. (Nostocales, Cyanobacteria): convergent evolution resulting in a cryptic genus

Abstract

Two populations of Rivularia-like cyanobacteria were isolated from ecologically distinct and biogeographically distant sites. One population was from an unpolluted stream in the Kola Peninsula of Russia, whereas the other was from a wet wall in the Grand Staircase-Escalante National Monument, a desert park-land in Utah. Though both were virtually indistinguishable from Rivularia in field and cultured material, they were both phylogenetically distant from Rivularia and the Rivulariaceae based on both 16S rRNA and rbcLX phylogenies. We here name the new cryptic genus Cyanomargarita gen. nov., with type species C. melechinii sp. nov., and additional species C. calcarea sp. nov. We also name a new family for these taxa, the Cyanomargaritaceae.

Uncovering cryptic diversity of Lyngbya: the new tropical marine cyanobacterial genus Dapis (Oscillatoriales)

“…, Shalygin et al. ). The number of detectable morphological characters is often limited and many phenotypes are plastic, depending on environmental conditions (Komárek ).…”

“…As for the majority of microorganisms, phenotypic characters applied to classify cyanobacteria have repeatedly been shown to greatly underestimate natural diversity (Sherwood et al 2015, Dvo r ak et al 2015, Shalygin et al 2017. The number of detectable morphological characters is often limited and many phenotypes are plastic, depending on environmental conditions (Kom arek 2011).…”

Two new species of Phyllonema (Rivulariaceae, Cyanobacteria) with an emendation of the genus

“…, Shalygin et al. , others). When morphological diversity among populations exceeds genetic diversity, it is generally assumed that this variability is due to plasticity in response to environmental variability, and generally no new taxa are described.…”

“…), whereas Cyanomargarita has been described as a cryptic genus inseparable morphologically from Rivularia (Shalygin et al. ). Kyrtuthrix and Nunduva belong to a clade of marine Rivulariaceae that has a number of potentially new genera and species based on phylogenetic and morphological evidence (León‐Tejera et al.…”

“…Recent molecular systematic studies on tapering cyanobacteria traditionally assigned to the Rivulariaceae have shown that the large classical genera Calothrix and Rivularia actually represent a number of genera if monophyly within genera is to be maintained. Calochaete, Roholtiella, and Macrochaete have been split out of Calothrix (Hauer et al 2013, Bohunick a et al 2015a, Berrendero et al 2016, whereas Cyanomargarita has been described as a cryptic genus inseparable morphologically from Rivularia (Shalygin et al 2017). Kyrtuthrix and Nunduva belong to a clade of marine Rivulariaceae that has a number of potentially new genera and species based on phylogenetic and morphological evidence (Le on-Tejera et al , Gonz alez-Resendiz et al 2018.…”