File:Laguna Negra microbial mats, macroscopic.jpg

English: (A) Optical microscopy image of a Rivularia filament (Riv.) with which numerous microorganisms are associated, hence suggesting the presence of a consortium (Cons.) (dotted circle). A large mineral aggregate is also visible near the filament (red arrow). Sulfur filaments (SF.), diatoms (Diat.) and mineral grains (Min.) can also be observed around the filament. From (B–D): Composite CSLM images obtained over an integrated depth of 50 μm by concomitant excitations at 405, 488, and 543 nm and collection between 425 and 475 nm, 500 and 530 nm, and 560 and 660 nm, respectively. (B) Composite CLSM image of a consortium surrounding a Rivularia filament distinguished in red due to its photosynthetic pigments. Inside the consortium, abundant cocci-shaped cells are observed thanks to Syto®9 staining (green) (c1, c2, and c3). Minerals appear in light blue due to laser reflection (white asterisk). Other filamentous cyanobacteria (f.Cya) are observed. (C) High magnification composite CLSM image of a Rivularia filament where cells are visible (in red) inside the sheath (sh.), which is covered by a myriad of Syto®9-stained cells. (D) Detail of a Rivularia filament associated with sulfur-bearing bacterial filaments (bright blue dots due to laser reflection). (E) Magnified SEM image in backscattered electron mode showing a Rivularia filament and the associated sulfur-bearing filaments (black arrow) with sulfur grains (SG.) appearing as bright dots. (A,B,D,E) were obtained on BP13 mat samples, while (C) was observed on BP15 mat sample after laser microdissection.