listeria marthii listeria marthii listeria marthii is a species of bacteria. it is a gram-positive, motile, facultatively anaerobic, non-spore-forming bacillus. it is non-pathogenic, and non-hemolytic. the species was first isolated from finger lakes national forest in new york. it is named after elmer h. marth, a researcher of l. monocytogenes, and was first published in 2010. l. marthii was the first new species of listeria proposed since 1985. listeria marthii scientific classification domain: bacteria phylum: bacillota class: bacilli order: bacillales family: listeriaceae genus: listeria species: l. marthii binomial name listeria marthiigraves et al. 2010 listeria marthii has mainly been isolated from a specific area in the finger lakes national forest. however, l. marthii strains may be mischaracterized as l. innocua due to biochemical similarities between the two species.