Which Gram-negative, anaerobic cocci is known to produce red fluorescence under ultraviolet light?

Veillonella is a genus of Gram-negative, anaerobic cocci that is notably characterized by its ability to produce red fluorescence when exposed to ultraviolet light. This fluorescent property is a distinguishing feature of Veillonella species, which can be useful in clinical microbiology for identification purposes.

The red fluorescence observed under UV light is due to the presence of specific porphyrins and other fluorescent compounds produced by Veillonella during its metabolic processes. This attribute helps distinguish it from other similar Gram-negative anaerobes, facilitating accurate diagnosis in laboratory settings.

In contrast, while Fusobacterium, Prevotella, and Nasococcus may be important genera of anaerobic bacteria, they do not exhibit the same characteristic fluorescence under UV light. Thus, Veillonella stands out in this context as the correct choice based on its unique properties.