Cold climate ecosystems hint the researchers to discover economically native cold-adapted strains, which can tolerate temperature fluctuations in outdoor large-scale cultivation for producing lipids as biofuel or for nutritional applications. Cheshmeh-Sabz Lake (Iran) was screened in winter. The lake water was sampled at 5 °C and three strains of Scenedesmus sp. (dominant in BG-11), Ankistrodesmus sp. (dominant in WC), and Chlorella sp. (dominant in BBM) were identified using molecular methods. Strains\\\\\\\\\\\\\\\' growth parameters, lipid content, and lipid productivity were also investigated at 8 °C and 25 °C. Scenedesmus sp. had the most biomass productivity ( 0.54±0.001 g/L*d) with no significant difference at 8 °C and 25 °C and demonstrated the highest amount of lipid productivity at 25 °C (9.43±1.05 g/L*d). Scenedesmus sp. produced the highest percentage of α-linolenic acid at 15 °C and 25 °C (10.96±1.5% and 11.07±0.31%, respectively) among the strains. There was no significant difference for palmitic acid content at 8, 15, and 25 °C (41.05±5.2, 38.48±4.25, and 39.82±1.58% respectively). Biomass productivity decreased in Ankistrodesmus sp. and Chlorella sp. at 8 °C in comparison to that of 25 °C (~86% and ~34% decrease, respectively). Ankistrodesmus sp. produced the highest proportion of α-linolenic acid at 8 °C (9.98±0.10%). The highest percentage of palmitic acid was observed in Chlorella at 25 °C (44.41±7.56%). Based on the results, Scenedesmus sp. is the proper choice for outdoor cultivation at different seasons due to its relatively high biomass productivity and the specific growth rate in low and high temperatures (8 and 25 °C).

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