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

Tropical cyanobacteria are an enigmatic group, often overlooked due to undersampling, yet expected to yield tremendous biodiversity. Many recent taxonomical studies have reported the existence of polyphyletic genera complexes in cyanobacteria (cryptogenera), where morphological coherent groups (often hardly distinguishable) have polyphyletic origins. In this paper, we employed a combined genetic and phenotypical approach to describe some newly isolated Pseudanabaena-like cyanobacteria from a lake in Vietnam. We found that two studied strains belonged to the monophyletic clade outside of the Pseudanabaena sensu stricto, thus it may be designed as a new genus, which has been called Pinocchia. However, there are only minor morphological differences from the other Pseudanabaena species. Thus, it may be considered as example of the cryptic genus. Moreover, it is additional evidence for a polyphyletic origin of the genus Pseudanabaena.