Table 1.

Sample collection metadata.

Sample ID	Type	Site	SC (mS/cm)a	pHb	Description
LCT14M-09	Thrombolite	1	130.2	7.63	Dark green microbial mat growing on small thrombolites (<20 cm diameter)
LCT14M-12	Thrombolite	2	121.4	7.54	Green EPS-rich mat growing on thrombolites
LCT14M-14	Thrombolite	2	121.4	7.54	Desiccated green EPS-rich mat growing on thrombolites
LCT14M-11	Sediment	2	121.4	7.54	Loosely cohesive microbial mat growing on sediment
LCT14M-22	Sediment	3	124.8	7.54	Loosely cohesive microbial mat growing on sediment
LCT14M-21	Sediment	4	188.2	7.18	Cohesive microbial mat growing on sediment, gray in color

^aSpecific conductance (SC) of lake water at sampling site. For comparison, Indian Ocean SC measured 55.82 mS/cm.

^bpH of lake water at sampling site.