Endolithic Phototrophs from an Active Geothermal Region in New Zealand

Abstract

Endolithic photosynthetic communities in geothermal siliceous rocks in the area of Rotorua, New Zealand, were analysed using traditional microbiological and molecular biology techniques. Rock surface temperatures varied between 40°C and 60°C. Major endoliths included cyanobacteria of subsections I, II and V. Few subsection IV organisms were found and subsection III (filamentous, non-heterocystous) cyanobacteria were present only as epiliths or chasmoendoliths. Therefore, the endolithic cyanobacterial communities in these sites resembled assemblages as reported for carbonate rocks in other geothermal regions. Cells of the rhodophyte family Cyanidiaceae were detected within rock at various sites. Some of these phototrophic organisms were associated with mineral (presumably silica) deposits and could be important geological agents in siliceous rock deposition.