Guilherme Scotta Hentschke*, João Morais*, Flavio Luis de Oliveira, Raquel Silva, Pedro Cruza nd Vitor Vasconcelos
Abstract: In this paper, we used the polyphasic approach combining 16S rRNA gene phylogenies, identity (p-distance), 16S-23S ITSsecondary structures, and morphological and habitat analyses to describe two new genera of Leptolyngbyaceae,Pseudoleptolynbgya G.S. Hentschke gen. nov. (based on LEGE 16533 and LEGE 16651) and Leptolyngbyopsis G.S.Hentschke gen. nov. (based on LEGE 16524). These strains were sampled from freshwater environments at Figueira daFoz, Monchique and Coimbra, Portugal. Both genera are morphologically and ecologically identical to Leptolyngbya andcan only be distinguished from it by molecular analyses. Based on morphological and ITS secondary structure analyses wedescribe two species of Pseudoleptolyngbya, P. figueirensis and P. monchiquensis. P. figueirensis differs fromP. monchiquensis by the denser arrangement of the trichomes, the presence of firm sheaths, the common formation ofshorter trichomes (up to 30 cells), and the olive or yellowish-green cell content, which is darker in P. monchiquensis.Moreover, the macroscopic appearance of P. figueirensis is a dense brownish mat, while P. monchiquensis is less dense andreddish. 16S rRNA gene sequences of Arthronema africanum CCALA020 are > 99% identical to Leptolyngbya boryanaPCC6306, so we transfer A. africanum to Leptolyngbya, as L. africanoidea.