thermocrinis ruber thermocrinis ruber thermocrinis ruber is a species of bacteria. it is a pink-filament-forming hyperthermophilic bacterium first isolated from yellowstone national park. its cells are gram-negative and grow at temperatures up to 89 °c. its type strain is oc 1/4 . thermocrinis ruber scientific classification domain: bacteria phylum: aquificota order: aquificales family: aquificaceae genus: thermocrinis species: t. ruber binomial name thermocrinis ruberhuber et al. 1999