Pseudoselenomonas

Pseudoselenomonas is a genus of obligately anaerobic, Gram-negative, non-spore-forming bacteria in the family Selenomonadaceae. Members of the genus have been isolated from the rumen contents of cattle and goats.

Members are motile and ferment carbohydrates to organic acids, including acetate and propionate. The genus contains four species with validly published names.

Taxonomy

The genus was established in 2026 during a phylogenetic and comparative genomic re-evaluation of the family Selenomonadaceae. Three species formerly classified in Selenomonas, Selenomonas caprae, Selenomonas ruminantium, and Selenomonas ruminis were transferred to Pseudoselenomonas. Selenomonas ruminantium subsp. lactilytica was elevated to species rank as Pseudoselenomonas lactilytica.

The name combines the Greek word pseudes, meaning "false", with the bacterial genus name Selenomonas, and therefore means "false Selenomonas". The type species is Pseudoselenomonas ruminantium.

Phylogeny

The following tree is derived from the genome-based phylogeny of Genome Taxonomy Database (GTDB) release R11-RS232. In this release, these species are classified in the placeholder genus Selenomonas_A. The tree has been pruned to the four species with validly published and correct names in LPSN, and their names have been updated to the current nomenclature.