Nepenthes under Ultraviolet Light.

[lloyd]

This is a N. rafflesiana under a soft UV BL tube. There are irregular yellow glowing patches around the periostome. Perhaps these could guide insects to the pitcher.

Here's the article that led to the picture.

www.smithsonianmag.com/science-nature/these-carnivorous-plants-glow-under-ultraviolet-light-to-attract-prey-180948058/

[Dave Evans]

The nectar glows. It acts as a brightener, mythinks.

[lloyd]

Aug 6, 2015 2:40:21 GMT Dave Evans said:

The nectar glows. It acts as a brightener, mythinks.

That's a good thought. I just checked it out. The yellow parts really follow the ridges and look like they are a part of the periostome itself. I tried spraying with a jet of distilled water and swabbing with a moistened cotton applicator and it didn't come off or smudge, just got a bit brighter as if I was cleaning the periostome off. So I think the yellow splotches are part of the periostome and not nectar.

[coline]

Interesting, I've only seen the purple colors, never yellow on them, but well, I don't have any big raffs to try, only hookerianas

[fredg]

Is the camera set on the normal image settings?

[lloyd]

I didn't even think about special settings except for no flash and macro. I'll have to play with it. The picture looks exactly like it did to my eyes.

[fredg]

Precisely the point, our eyes don't see what the insect's eyes see.

[lloyd]

H. tatei tatei and U. reniniformis under soft BL UV light. Mild fluorescence.

[lloyd]

The ceph definitely had some fluorescence under the lid, red-orange and some other colours.

The various sarrs also fluoresced.