The Fluorescent Desert

The New Mexican desert under visible light appears in browns and greens (depending upon the time of year), but after dark and under long wave ultraviolet light the desert lights up like Christmas.  The recent purchase of a long wave UV black light flashlight for use in cleaning at the Painted Pony Resort was co-opted to explore the desert at night.  The LSU Arthropod Museum has always set up a black light trap on the property during their yearly visits and this idea was expanded with a hand held black light.  Wandering about in the desert in the dark with a UV light might seem odd but the abundance of fluorescing material makes it a worthwhile effort.  A frequent use of a black lights is scorpion hunting and a number Arizona bark scorpions were found in the desert.  They glow brightly under UV light and are easily visible from 10' away.  Other biological materials also fluoresce, especially lichens.  Some lichen species glow a bright orange and are easily picked out on rocks in the desert.  Teeth will also fluoresce, especially when using whiteners, and a check of the fossil horse teeth recovered recently confirmed that very old teeth also fluoresce to some extent appearing a bluish white under UV light.

While still learning how to photograph fluorescing materials using ultraviolet light, a few examples that are somewhat presentable are shown below.

black light insects
An Arizona bark scorpion under long wave black light.

UV minerals
Green fluorescent chalcedony
Fossil horse teeth under black light


  1. The black light is a great tool for cleaning then fun outside after dark. Good pictures!

  2. I agree, a very useful cleaning tool. But I like looking at the desert landscape at night the best. I have to work on the photography though to get better images, a large landscape image would be really cool but it will take some experimentation.

  3. A bark scorpion 10 feet away? can we hire you to come look for them here? ew.

  4. oh wait, an Arizona bark scorpion? I live in New Mexico and they wouldn't cross the state line, would they? hee hee

  5. I found little ones out in the desert that were only about 1 mm long. The black light would catch a flash of fluorescence and I would get down to investigate and there was a tiny little scorpion. With respect to crossing the state line, I can not find it in the desert so I suspect the scorpions can not find it either.