Table 1. Classification and general features of D. mucosus 07/1^T according to the MIGS recommendations [25].

MIGS ID	Property	Term	Evidence code
	Current classification	Domain Archaea	TAS [26]
		Phylum Crenarchaeota	TAS [27,28]
		Class Thermoprotei	TAS [27,29]
		Order Desulfurococcales	TAS [27,30]
		Family Desulfurococcaceae	TAS [2,3,31]
		Genus Desulfurococcus	TAS [1,3,32]
		Species Desulfurococcus mucosus	TAS [1,3]
		Type strain O7/1	TAS [1]
	Gram stain	negative	TAS [1]
	Cell shape	spheroid, often in pairs	TAS [1]
	Motility	non-motile	TAS [1]
	Sporulation	none	NAS
	Temperature range	76°C-93°C	TAS [23]
	Optimum temperature	85°C	TAS [1,23]
	Salinity	around 0	TAS [23]
MIGS-22	Oxygen requirement	strictly anaerobic	TAS [1]
	Carbon source	yeast extract, casein or its tryptic digest	TAS [1]
	Energy metabolism	organotroph	TAS [1]
MIGS-6	Habitat	fresh water, sulfur spring	TAS [1]
MIGS-15	Biotic relationship	free living	TAS [1]
MIGS-14	Pathogenicity	none	NAS
	Biosafety level	1	TAS [33]
	Isolation	acidic hot spring	TAS [1]
MIGS-4	Geographic location	Askja, Iceland	TAS [1]
MIGS-5	Sample collection time	1981 or before	TAS [1]
MIGS-4.1	Latitude	65.05	NAS
MIGS-4.2	Longitude	-16.8	NAS
MIGS-4.3	Depth	not reported	NAS
MIGS-4.4	Altitude	approx. 1,053 m	NAS

Evidence codes - IDA: Inferred from Direct Assay (first time in publication); TAS: Traceable Author Statement (i.e., a direct report exists in the literature); NAS: Non-traceable Author Statement (i.e., not directly observed for the living, isolated sample, but based on a generally accepted property for the species, or anecdotal evidence). These evidence codes are from of the Gene Ontology project [34]. If the evidence code is IDA, then the property was directly observed by one of the authors or an expert mentioned in the acknowledgements.