Table 2.

Abundant taxonomic groups in the archaeal clone libraries for each habitat.

Habitat	Site	Temp range of venting fluids (°C)	Relative abundant group (potential chemolithoautotrophs)	Potential electron donor*	Growth temperature*
Active sulfide structure	Snail, Pika, Archaean	19–341	Archaeoglobi, Thermoprotei	Hydrogen	(Hyper)thermophiles
Deep seawater	Snail, Pika, Archaean	2–3	MGI	Ammonia	Psychrophiles
Borehole fluid	Snail, Pika	6–40	MBGE, MGI, pSL12-related	Iron (?), ammonia	Mesophiles (?)
Iron-rich mat	Snail	33–116	MBGE, MGI, pSL12-related	Iron (?), ammonia	Mesophiles (?)

*Based on the physiological characteristics inferred from the phylogeny of the phylotypes.