Preliminary observations of skeletal UV fluorescence in fresh and preserved snakes

Abstract

Biofluorescent tissues in vertebrates are commonly observed phenomena that have been found in a wide
variety of taxonomic groups. The fluorescence of bone has recently been found visible through the skin in some squamates,
although its function is poorly known. While this phenomenon has been observed in lizards, no published
records of ultraviolet (UV)-based fluorescence exist for snakes. We present the first published record of bone-based
fluorescence of snakes using museum skeletal specimens and fresh dead-on-the-road (DOR) specimens (24–48 h postmortem)
gathered during field observations. Nine of 11 families tested fluoresced in the presence of a UV alternative
light source. We found that snake bones emitted brighter blue/green light in DOR specimens than the dull green color
in older museum specimens. Fluorescence, though brighter in fresh specimens, was still observed in museum specimens
as old as 95 years. We herein present observations to provide baseline data for fluorescence-related studies in snakes.
We remain uncertain if the light emitted from bones is visible through the skin and scales of living snakes and identify
this as an important area for future investigations.