On February 16th 2015, I went out reef walking at night during low tide. I brought my Light and Motion Nightsea blue light in search of marine life fluorescence. I stumbled upon an interesting find in the world of science. I call it Fluoro fingerprinting.
I flipped over a rock, a small sea cucumber fell off and began to fluoresce under blue light. I found another sea cucumber and photographed it using the blue light and yellow excitation filter but it did not fluoresce.
Holothuria (Platyperona) difficilis under blue light
I gently touched it with my finger and it fluoresced bright green, leaving the print of my finger on the surface of the sea cucumber.
Fluoro fingerprinting. Okinawa-Japan
I checked my finger and noticed it fluoresced light green under blue light.
I was excited about this find and posted it Flickr for some Identification help and explanation. Curt Fieldler emailed the photograph to Dr Alexander Kerr from the University Of Guam Marine lab and he was kind enough to assist.
Dr Kerr stated that the species is known to have green pigment that I have seen in other Sea cucumbers. As far as the fingerprint, It seems to indicate that touching the surface of the Sea cucumber exposes the underlying carotenoid, perhaps by mobilizing the the melanin pigments. So I think you have made an interesting find.
The next step was to photograph Holothuria (Platyperona) difficilis in a studio aquarium using the Meet your neighbours isolation technique. I wanted to show the animal stretched out displaying the tube feet and feathery feeding tentacles.
Holothuria (Platyperona) difficilis -MYN
The last step was to photograph Holothuria (Platyperona) difficilis in its natural environment during the daytime.
Holothuria (Platyperona) difficilis in natural environment
Learn more about capturing fluorescence http://www.nightsea.com/
Learn more about the lights used http://www.lightandmotion.com/
Learn more about Meet your Neighbours Project http://meetyourneighbours.net/
Have a great day!