The description is based on Grimont and Grimont (2005), Izard et al. (1981), Brenner et al. (1986) and this study. Cells are straight rods, 0.6–1.0 μm × 1.5–3.0 μm, motile by peritrichous flagella. Gram negative. Facultatively anaerobic. Optimum temperature for growth is 30 °C, grows at 37 °C but not at 41 °C. Colonies are unpigmented, round, convex and smooth with entire margins on tryptone soya agar. Positive for Voges-Proskauer and ornithine decarboxylase, but negative for lysine decarboxylase, gelatinase, indole and H2S production. Variable for arginine dihydrolase. Nitrate is reduced to nitrite. Glucose is fermented with production of acid and gas. N-acetyl-d-galactosamine, N-acetyl-d-glucosamine, l-arabinose, d-cellobiose, d-fructose, d-galactose, gentiobiose, d-glucose, lactose, maltose, d-mannitol, d-mannose, d-melibiose, d-raffinose, l-rhamnose, d-trehalose, d-gluconic acid, d-saccharic acid, glycerol, α-d-glucose-1-phosphate, d-glucose-6-phosphate are oxidized (Biolog), whereas tweens 40 and 80, d-arabitol, m-inositol, cis-aconitic acid, p-hydroxy-phenylacetic acid, itaconic acid, propionic acid, l-alaninamide, l-proline, l-threonine, 2-aminoethanol and 2,3-butanediol are not. Reactions to d-sorbitol, sucrose, turanose, succinic acid mono-methyl ester and d-serine are variable. Major fatty acids are C16:0, C18:1ω7c, C17:0 cyclo and summed features 2 (iso-C16:1 and/or C14:0 3-OH) and 3 (C16:1 ω7c and/or iso-C15:0 2-OH), with C17:0 cyclo and summed feature 3 representing more than 30% of the total amount. Members of the genus Lelliottia form a clade using MLSA based on concatenated partial gyrB, rpoB, infB and atpD sequences. G + C contents range from 54.0 to 55.0 mol%.

Lelliottia species are isolated from elm trees exhibiting symptoms of “wetwood” disease, water and rarely from clinical samples.

The type species is Lelliottia nimipressuralis (Carter 1945) Brenner, McWhorter, Kai, Steigerwalt and Farmer (1986).