A UNIQUE PSEUDANABAENALEAN (CYANOBACTERIA) GENUS NODOSILINEA GEN. NOV. BASED ON MORPHOLOGICAL AND MOLECULAR DATA¹

Abstract

The cyanobacteria are a diverse, ancient lineage of oxygenic, phototrophic bacteria. Ubiquitous in nearly all ecosystems, the alpha-level diversity of these organisms lags behind other algal lineages due to a perceived dearth of phylogenetically useful characters. Recent phylogenetic studies of species within the genus Leptolyngbya have demonstrated that this is a polyphyletic assemblage. One group of strains that fits within the current circumscription of Leptolyngbya is genetically and phylogenetically distinct from Leptolyngbya sensu stricto. Members of this clade possess both a morphological synapomorphy and shared 16S-23S internal transcribed spacer (ITS) secondary structure, allowing the diagnosis of the new cyanobacterial genus Nodosilinea. Members of this genus are united by the unique ability to form nodules along the length of the filament. This trait has been previously observed only in the species Leptolyngbya nodulosa Z. Li et J. Brand, and we have chosen this species as the generitype of Nodosilinea. We currently recognize four species in the genus, N. nodulosa (Z. Li et J. Brand) comb. nov., N. bijugata (Kong.) comb. nov., N. conica sp. nov., and N. epilithica sp. nov.

A new tropical cyanobacterium Pinocchia polymorpha gen. et sp. nov. derived from the genus Pseudanabaena

“…Our 16S rRNA tree largely corresponds to other recently published phylogenies (e.g. Perkerson et al 2011;daGan et al 2013;komárek et al 2014) Hašler et al 2014;osorio-santos et al 2014 and many others). We found high variability among clones and between both isolated strains (Fig.…”

Species concepts and speciation factors in cyanobacteria, with connection to the problems of diversity and classification

“…They also designed a concrete species definition based on the mentioned concept, which is suitable for cyanobacteria and may be used under the International Code of Botanical Nomenclature. It is probably the most widely accepted concept with cyanobacteria (according to the number of taxonomic papers using the concept under the Botanical Code), although sometimes not precisely followed (Siegesmund et al 2008;Perkerson et al 2011;Dvořák et al 2014a;Hašler et al 2012Hašler et al , 2014aOsorio-Santos et al 2014 and many others). The most important advantage of the monophyletic species concept is the general applicability to asexual organisms.…”

A revision of the genus Geitlerinema and a description of the genus Anagnostidinema gen. nov. (Oscillatoriophycidae, Cyanobacteria)

“…Historical reliance on only few markers, e.g., lack of visible sheath or its pigmentation, filament tapering, length of cells, etc., led to the erection of genera that subsequently have been demonstrated to be polyphyletic according to 16S rDNA sequence analyses (e.g. komárek & anagnoStidiS 2005;perkerSon et al 2011;chatchawan et al 2012;komárek et al 2014). As a consequence of findings based on the 16S rRNA gene, re-evaluation of the corresponding cytomorphological and ecological features is necessary.…”