Scorpions are known to reflect UV light on their surface and change it into a greenish visible light, spiders are not known to do so. Which Arachnids share this phenomenon with the scorpions?
From personal experience, I know that some (but not all) species of spiders fluoresce strongly under UV light. There are many good examples of this available through a quick google image search.
Dear Eric,
I cannot find any reliable source with a statement about the UV-fluorescence of pseudoscorpiones.
Rudolf - I usually take a portable UV light with me when I go camping. I'll try to track down some pseudoscorpions this summer and test it out myself. I'll let you know if I come up with anything.
Hey Rudolf! The question is pretty curious! I never saw a false scorpion under UV light: some time ago, searching Opiliones and scorpions, I tried to test UV light to look for pseudoscorpions, I test with some individuals of Ideobisium (Syarinidae), Cystowithius (Withiidae), Apolpium and Pachyolpium (Olpiidae), Cordylochernes, Parachernes, and other chernetids, but I didn't get results (In highland).
Hello Fabián,
"but I didn't get results", does it mean, that the pseudoscorpions above definitely do not glow under UV-Light?
I took this picture just for fun some years ago simply putting a cheap UV torch against an alcohol-preserved specimen of G. italicus. Differently from scorpions seems that the sclrerotized part don't reatc to UV radiation. Membranes appear to better react to the light.
Dear Matteo,
thank you for your contribution, it gets even more interesting!
It would be interesting to see if some troglophilous or cave-related species have different reaction to UV radiations
Dear Gerardo,
thank you for your contribution! Do you have a photo of this tick?
The membranes at the joints seem to reflect more radiation similar to that of the pseudoscorpion above, but really much more discretely.
The other light points might be artefacts/dust?
Hi everyone!
I just tried it and I think it works! (at least with a female). It was with specimens preserved in ethanol. Attached are the pictures.
Phantastic pictures, do you think, there may be really a difference in fluorescence depending on the gender?
Rudolf Ritt anticipated my next question: do living pseudoscorpions use uv- fluorescence as mating or as communication patterns? I've never analysed or read anything about the eye structure of these arachnids...
Hi Rudolf!
Sorry for the late response. I try it again with ethanol preserved specimens. Maybe is the fluorescence do not depend on gender, more work is needed but it is an interesting topic.
More (sorry, I think we can´t add more than one file, not without an answer)
Dear Solanlly,
thank you for this beautiful pictures! All the pictures show, that - in opposite to the scorpions - the sclerotized parts do not react, the membranous parts react to UV radiation.
Some specimen seem to not react at all. I would really like to know why!
Hi Rudolf Ritt
Finally I used an UV light with live specimens, as you can (hopefully) see in the video they didn´t glow.
I suppose that the ethanol makes them more translucent, but I have little expertise in that area.
Let me know if you can see the video.
Dear Solanlly,
Thank you for the video, but it is really difficult to see an effect/no effect. But you really saw no effect, right? Do you know which species they are??
Rudolf Ritt
They belong to the same genus. actually, the ones in the video I collected in a cave, so I was curious to see their reaction with the uv light.
Now I´ll try with the same individual but now in ethanol.
Stay tuned :-)
Rudolf Ritt
Update: Apparently, recently collected pseudoscorpions (in 70% ethanol) don´t reflect uv light, but I found that inmature opiliones do (see images, they glow in an red/orange color).
First with normal light.
It would be great if they did! Working in caves, I have brought a ultraviolet light with me and tried this. I can say that at least with some chernetids and chthoniids, they do not. I have not tried with the same ethanol-preserved specimens.
Dear Charles,
thank you for your distribution!
You think, that the ethanol-preservation may change the UV-fluorescence?
This is turning into a really interesting thread. If somebody were to gather a bit more data, this would be a great topic for a brief note in a journal.
Eric Dexter I agree with you. Actually, I was gathering all the information available about this topic and could write a summary of it for the intention to publish a brief note, however, I realize this extends beyond my area of expertise.
This is a nice announcement, Gabriel! Do you have some specimens to test this?
To find out, if this is an artefact, I think one has to test the identic specimens alive and afterwards preserved in 70 % ethanol. Perhaps it may last some time (years???) to observe the decay and the change of the UV-fluorescence?
When I tried with my UK specimens they didn't seem to glow which is a shame as it would certainly help in finding them in their habitat.
Solanlly Carrero-Jiménez the images you showed are harvestmen, not pseudoscorpions (for those that don't know this). They remind me of Bishopella spp. I have collected in caves of the eastern US. Still, also interesting!
The video was interesting further evidence that psuedoscorpions at least from caves don't fluoresce.. in the movie are these neobisiids?
Rudolf Ritt et al. I would be happy to collaborate with anyone interested on this thread to write a note about this. I have representatives of several families available to me that are preserved in EtOH & can get live representatives of a few families relatively easily (from southeastern Alabama, USA) to test surface-dwelling animals from under bark and in leaf litter for comparison.
Charles D. R. Stephen Hi, thanks for your clarification, I was mixing those two groups in the answers.
The pseudoscorpions in the video are chernetids that were collected inside a cave.
- Badges
- Science topic
- Similar topics
- Biological Science
- Biota
- Eukaryota
- Fungi