Toto Vent

Latitude: 12.71333^οN Longitude: 143.52833^οE Depth: 3035 m bsl

Alternative Names: Toto caldera, Nakayama field (Gamo et al., 2004)

Toto caldera is located in the southernmost Mariana trough and is considered to be an arc volcano in the Mariana Arc (Embley et al., 2004). White smoker hydrothermal fluids were observed with temperature of 170^οC and very low pH which is about 1.6. The chimneys consist of elemental sulfur (Nakagawa et al., 2006). Among the biological community, ɛ-Proteobacteria dominates the microbial community in the sulfur chimneys while archaea are minor (Nakagawa et al., 2006).

Table 1: Operations history for Toto vent

Ship/ Platform	Year	Dive Number	References
KH-98-1 R/V Hakuho Maru cruise Leg-3	Not found	Not found	Gamo et al., 2004
YK03-07 Yokosuka/ Shinkai 6500	2003	0772-0776	YK03-07 cruise report

Table 2: Vent activity and host rocks

Activity and host rocks

References

Activity

Active

Gamo et al., 2004;

InterRidge Vents Database Ver. 3.3.

Table 3: Vent fluid characteristics

Vent Fluids		References
Temperature (^οC)	170- 22	Nakagawa et al., 2006
pH	1.6-5.4	Nakagawa et al., 2006
Composition	White smoker hydrothermal fluids with low pH, low alkalinity and sulfate concentration	Nakagawa et al., 2006
CO₂ (mM)	15.3	Gamo et al., 2004
Mn (nmol/kg)	47	Gamo et al., 2004
Fe (nmol/kg)	112	Gamo et al., 2004
CH₄(nmol/kg)	9.9	Gamo et al., 2004

Table 4: Vent Biology

General name	Phylum	Class/Order	Family/ Genus	Species	References
Archaea					Nakagawa et al., 2006
Archaea	Euryarchaeota	Archaeoglobi	Archaeoglobus		Takai et al., 2011
Archaea	Euryarchaeota	Methanococci	Methanococcales		Takai et al., 2011
Archaea	Euryarchaeota	Thermococci	Pyrococcus		Takai et al., 2011
Archaea	Euryarchaeota	Thermococci	Thermococcus		Takai et al., 2011
Bacteria	Aquificae	Aquificae	Aquifex		Takai et al., 2011
Bacteria	Aquificae	Aquificales	Desulfurobacteria		Takai et al., 2011
Bacteria	Aquificae	Aquificales	Persephonella		Takai et al., 2011
Bacteria	Bacteroidetes	Bacteroidetes	Rhodothermus		Takai et al., 2011
Bacteria	Deferribacteres	Deferribacterales	Deferribacter		Takai et al., 2011
Bacteria	Firmicutes	Clostridia	Tepidibacter		Takai et al., 2011
Bacteria	Proteobacteria		Hydorgenimonas		Takai et al., 2011
Bacteria	Proteobacteria		Nautiliales		Takai et al., 2011
Bacteria			Thermaceae		Takai et al., 2011
Bacteria			Nitratiruptor		Takai et al., 2011
Bacteria	Proteobacteria	Epsilonproteobacteria	Sulfurovum		Takai et al., 2011
Bacteria	Proteobacteria	Thiotrichales	Piscirickettsiaceae	Thiomicrospira thermophila	Takai et al., 2004
Bacteria	Proteobacteria	Campylobacterales	Sulfurimonas		Takai et al., 2011
Bacteria			Thioreductor		Takai et al., 2011
Bacteria	Proteobacteria	Gammaproteobacteria	Thiomicrospira		Takai et al., 2011

Images:

J-EDI JAMSTEC E-library of Deep-sea Images; SHINKAI 6500 0776 http://www.godac.jamstec.go.jp/jedi/shot_search_main.jsf?LANG=EN note: search “Toto”

Videos Links:

J-EDI JAMSTEC E-library of Deep-sea Images; http://www.godac.jamstec.go.jp/jedi/shot_search_main.jsf?LANG=EN note: search “Toto”

References:

Embley, R. W., Baker, E. T., Chadwick, W. W. JR., Lupton, J. E., Resing, J. A., Massoth, G. J., Nakamura, K., 2004. Explorations of Mariana Arc. Eos 85 (4), 37-44.
Nakagawa, T., Takai, K., Suzuki, Y., Hirayama, H., Konno, U., Tsunogai, U., and Horikoshi, K., 2006. Geomicrobiological exploration and characterization of a novel deep-sea hydrothermal system at the TOTO caldera in the Mariana Volcanic Arc: Environmental Microbiology 8 (1), 37-49.
Takai, K., Nakamura, K., 2011. Archaeal diversity and community development in deep-sea hydrothermal vents. Current Opinion in Microbiology 14, 282–291.

Website References:

InterRidge Vents Database Ver. 3.3 http://vents-data.interridge.org/ventfield/toto-caldera (accessed 10/03/2015)
JAMSTEC (Japan Agency for Marine Earth Science and Technology) E-library of Deep-sea Images (JEDI) http://www.godac.jamstec.go.jp/jedi/public/Sec102.jsf (accessed 10/03/2015)

Cruise Reports:

Yokosuka cruise report YK03-07 http://www.godac.jamstec.go.jp/catalog/data/doc_catalog/media/YK03-07_all.pdf