pyrococcus woesei pyrococcus woesei pyrococcus woesei is an ultra-thermophilic marine archaeon. it is sulfur-reducing and grows optimally between 100 and 103 °c. its cells have a roughly spherical, elongated and constricted appearance, similar to thermococcus celer. frequently, they occur as diploforms. cells grown on solid supports have dense tufts of flagella or pili attached to one pole. pyrococcus woesei scientific classification domain: archaea kingdom: euryarchaeota phylum: euryarchaeota class: thermococci order: thermococcales family: thermococcaceae genus: pyrococcus species: p. woesei binomial name pyrococcus woeseizillig, 1988 kanoksilapatham et al. propose p. woesei as a subspecies of p. furiosus. it is named after the discoverer of archaea as a whole - carl woese