Several recent studies suggest that scorpion cuticle plays a
role in UV detection (Kloock et al. 2010; Camp & Gaffin 1999;
Blass & Gaffin 2008; Gaffin et al. 2012). Kloock et al. (2010)
found that scorpions that had their fluorescence compromised
by photo-bleaching made more transitions between UV light
exposed and unexposed regions of Petri dish arenas than
untreated scorpions; also, fluorescent scorpions reduced their
activity under UV light at intensity levels similar to what we
present here. The authors discuss the possibility that scorpion
fluorescence is related to the detection of moonlight and the
decision to avoid foraging on nights with high moon
illumination; scorpions are less active on the surface during
moonlit nights than during moonless nights (Skutelsky 1996).
However, our results do not support this notion since animals
under UV levels that match the UV composition of full moon
nights showed no difference in behavior from animals under
no-light conditions. This does not mean that the animals are
not detecting and using UV at full moon levels; it simply
suggests that it does not act as a deterrent.