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USGS · 70034780

Ancient photosynthetic eukaryote biofilms in an Atacama Desert coastal cave

A. Azua-Bustos·C. Gonzalez-Silva·R.A. Mancilla·L. Salas·R.E. Palma·J.J. Wynne·C.P. McKay·R. Vicuna
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Abstract

Caves offer a stable and protected environment from harsh and changing outside prevailing conditions. Hence, they represent an interesting habitat for studying life in extreme environments. Here, we report the presence of a member of the ancient eukaryote red algae Cyanidium group in a coastal cave of the hyperarid Atacama Desert. This microorganism was found to form a seemingly monospecific biofilm growing under extremely low photon flux levels. Our work suggests that this species, Cyanidium sp. Atacama, is a new member of a recently proposed novel monophyletic lineage of mesophilic "cave" Cyanidium sp., distinct from the remaining three other lineages which are all thermo-acidophilic. The cave described in this work may represent an evolutionary island for life in the midst of the Atacama Desert. ?? Springer Science + Business Media, LLC 2009.

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A. Azua-Bustos, C. Gonzalez-Silva, R.A. Mancilla, L. Salas, R.E. Palma, J.J. Wynne, C.P. McKay, R. Vicuna. 2009-03-05. Ancient photosynthetic eukaryote biofilms in an Atacama Desert coastal cave. https://doi.org/10.1007/s00248-009-9500-5

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