Which characteristic differentiates Listeria monocytogenes from Corynebacteria species?

Listeria monocytogenes is characterized as a motile organism, particularly at room temperature, which helps distinguish it from Corynebacterium species, which are nonmotile. This motility trait is significant, as it affects the pathogenicity and ecological niche of Listeria. Additionally, Listeria can ferment salicin, whereas Corynebacteria are typically salicin negative.

The other characteristics listed do not serve as differentiators in this scenario. For instance, beta-hemolysis is not a distinguishing factor since both Listeria and some Corynebacterium species can exhibit varied hemolytic patterns depending on culture conditions and specific strains. Spore formation is another point of distinction, as neither Listeria monocytogenes nor Corynebacterial species form spores, contradicting any option mentioning spore formation. Finally, both organisms are Gram-positive and do not consist of Gram-negative rods, making that aspect non-differentiative as well.

Thus, the characteristic of being motile and capable of salicin fermentation is the key trait that sets Listeria monocytogenes apart from Corynebacteria species.