Inconstantimicrobium

Inconstantimicrobium is a genus of Gram-positive and strictly anaerobic bacteria in the family Clostridiaceae. The genus was first described in 2021 following the isolation and genome-based characterization of the type species, Inconstantimicrobium porci, from the feces of a domestic pig in Germany.^[1]

Inconstantimicrobium
Scientific classification
Domain:	Bacteria
Phylum:	Bacillota
Class:	Clostridia
Order:	Eubacteriales
Family:	Clostridiaceae
Genus:	Inconstantimicrobium Wylensek et al. 2021
Type species
Inconstantimicrobium porci Wylensek et al. 2021

Etymology

The name Inconstantimicrobium is derived from Latin: inconstans ("variable" or "inconstant") and microbium ("microbe"), referring to its variable morphology and growth behavior.

Species

As of 2025, two species have been validly published within this genus:

• Inconstantimicrobium porci – isolated from pig feces in Germany^[1]
• Inconstantimicrobium mannanitabidum – isolated from anoxic soil under reductive soil disinfestation treatment in Japan^[2]