We have recently shown that scent marking glands found on the ventral tail of Plethodon cinereus are biofluorescent. These glands fluoresce brightly under UV and blue light. Further, we have found that the fluorescence only occurs in adults and is sexually dimorphic with males having more, larger, and brighter glands than females. The function of the biofluorescence is currently unknown, but we suspect that it may be related to mate choice and/or territory defense. We are currently designing and executing studies to test those hypotheses.