Etymology: N.L. neut. n. hydrogenum, hydrogen (that which produces water, so called because it forms water when exposed to oxygen); from Gr. neut. n. hydôr, water; from Gr. v. gennaô, to produce; L. fem. n. virga, a slender green branch, a twig, rod; N.L. fem. n. Hydrogenivirga, hydrogen rod
Type species: Hydrogenivirga caldilitoris Nakagawa et al. 2004
Valid publication: Nakagawa S, Nakamura S, Inagaki F, Takai K, Shirai N, Sako Y. Hydrogenivirga caldilitoris gen. nov., sp. nov., a novel extremely thermophilic, hydrogen- and sulfur-oxidizing bacterium from a coastal hydrothermal field. Int J Syst Evol Microbiol 2004; 54:2079-2084.
Number of child taxa with a validly published and correct name: 2
Number of child taxa with a validly published name, including synonyms: 2
Total number of child taxa: 2
Parent taxon: Aquificaceae Reysenbach 2002
Assigned by: Gupta RS, Lali R. Molecular signatures for the phylum Aquificae and its different clades: proposal for division of the phylum Aquificae into the emended order Aquificales, containing the families Aquificaceae and Hydrogenothermaceae, and a new order Desulfurobacteriales ord. nov., containing the family Desulfurobacteriaceae. Antonie Van Leeuwenhoek 2013; 104:349-368.