Fig. 2: Filamentous structures preserved within the serpentine-hosted aragonite vein shown via transmitted light microscopy.
From: Microbial biosignature preservation in carbonated serpentine from the Samail Ophiolite, Oman
A Type A filaments anchored to the iron-encrusted polygonal zone wall. Filaments here display rounded terminal ends and occasional budding along stalks (black arrow). B Type A filaments among clusters of laminated and flocculent iron oxide precipitates. C Type A filament interspersed among iron oxides. D Type A filament showing branching at septate division. E Type A filament displaying narrow channel-like structure along septal division. F Example of potential anastomosing among Type A filaments. G Branching Type A filaments adjacent to a cluster of Type B filaments (outlined in red), indicating relative size difference between the two morphotypes. H Thin Type B filaments spanning across iron oxide precipitates. I Dense cluster of Type B filaments with some specimens resembling twisted stalks (white arrows).
