Wednesday 27 February 2013

Sunbeam Snake

Xenopeltis unicolor
It's the Sunbeam Snake, Xenopeltis unicolor!

Wait, unicolor? I'm seeing a lot more than just ONE colour!

These beautiful, metre (3.3 ft) long snakes are found in Southeast Asia. Under dull light they look plain brown with a lighter underbelly. In strong sunlight a mesmerising, iridescent sheen is revealed in all its rainbow glory.


Thing is, the Sunbeam Snake actually shuns strong sunlight! While they prefer the kind of open areas that could make for an excellent backdrop to show off their splendour, they mainly go there at night. The rest of their time is spent underground! Can you believe that?

Image: berniedup via Flickr
Unlike many other snakes, the Sunbeam has very little neck behind its wedge shaped head. This makes it that little bit easier to nose its way through the ground. They only bother with the surface when it's time to eat, at which point this non-venomous snake will overcome a wide range of prey by constriction.

Females lay up to 10 eggs which hatch into youngsters that look just like their parents except for a pale collar around the neck. This unsightly patch soon fades away as they grow into an impeccably modest shrinking violet. Also red, orange, yellow, etc.

6 comments:

Crunchy said...

Gorgeous, but... why? What's the advantage to being a rainbow snake?

Joseph JG said...

I found this overview of iridescence in general:

http://rsif.royalsocietypublishing.org/content/6/Suppl_2/S115.full

I couldn't read it all, though!

It seems like it's probably about communication, sexual selection and the usual stuff that happens at parties.

Perhaps they get into the sun when it's time to breed and stay in the dark looking all brown and camouflaged when it's not?

Or maybe it's to produce flashes of colour to ward off predators, sort of like those grasshoppers with the bright red hindwings.

And I've JUST seen that iridescent scales have a structure which reduces friction, which is pretty great for a burrowing reptile. It really is a "sheen"!

Thanks for the question, I've gone and learnt something!

TexWisGirl said...

wow, prettier than any jewelry!

Joseph JG said...

So true! And if you wear it, it'll move around all the time so it sparkles under the light. And it isn't venomous so it doesn't matter so much if it bites you repeatedly. It's perfect for the ball!

BK said...

What's the point of that colour I don't know...after all plenty of fossorial snakes are dull.

Joseph JG said...

Yeah, pretty odd. A lot of creatures have attributes that aren't strictly necessary, I guess if it doesn't actively get them killed it might just stay