Wednesday 4 January 2012

Sally Lightfoot (Grapsus grapsus)

Image: ConstantineD via Flickr
Woo! You look HOT! You're on FIRE! I think this crab knows I'm looking! And she knows that I know that she knows I'm looking. And I know that I know that she knows that I know that she knows that those rocks know that we know that... I'm confused.

Image: Wikipedia
It's a fantastic looking crab, though! They come from the Pacific coast of America, from Mexico all the way down to northern Peru and various islands nearby including the Gal├ípogos. Here, on all that black, volcanic rock, the Sally Lightfoot looks like an elemental creature that has risen up from the Earth's very core. They look like walking fire!

And then there's that fabulous name. It comes from their amazing speed and agility as they rush off from birds and other predators. Reaching 8 cm (3 in) across not including the legs, those beautiful eyes have to keep on the lookout for large carnivores. And of course, if you're so incredibly visible and evident you're gonna have to be light on your feet!

Luckily, the youngsters and gawky teenagers are black or dark brown. This works great for camouflage until they get their colours later on, even though it probably means they find the adults rather embarrassing.

Image: mrccos via Flickr
Juvenile Sally Lightfoot
Aside from that, Sally Lightfoots just sit around stuffing their face with tiny clawfuls of algae browsed from the surface of rocks. They are opportunistic omnivores, so eggs, carrion and whatever else is also good eating, but algae predominates.

I still think they're made of pure lava, though.


Anonymous said...

Why is a crab called Sally? Aside from that, they are incredibly beautiful! Especially when you look at that video, they really look like elemental because they look so fresh and vivid, like they have just been created! I guess I will have to visit their homeland some time in my life... I'll bring some fresh algae as sacrifice for them!

Joseph JG said...

They really seem to glow and sparkle splendidly! You should definitely bring a peace offering. I still feel like those black rocks could turn into fire-crabs at any moment.

Porakiya said...

I agree about the elemental thing. If you look halfway through the video, the inner sides of the claws have some sticky-out bits that make it look like they're on fire.

Joseph JG said...

Yeh, they look amazing! And surrounded by all that black rock, it's just perfect!