The Genus Pinnularia Ehrenberg (Bacillariophyceae) In A Floodplain Lake Of The Tapajos River (Verde Lake, Santarem, Para, Brazil)

This study aimed to carry out a taxonomic inventory of the genus Pinnularia in Verde Lake, a floodplain lake located on the right bank of the Tapajos River, in the Protection Area of Alter do Chao in Santarem. Samplings were carried out monthly using a plankton net (20 mu m) at four different stations, including limnetic and littoral zones, from July 2016 to June 2017. A total of 41 taxa, of which 29 species and 12 varieties were described, commented and illustrated with light microscopy and/or scanning electron microscopy micrographs. Pinnularia acuminata var. novazealandica Krammer, P. divergens var. media Krammer, P. graciloides var. rumrichae Krammer, P. parallela var. parallela Brun, P. percuneata var. percuneata Krammer and P. tumescens Metzeltin & Krammer are the first records for the Brazilian Amazon and 21 are documented for the first time for Para State.