SALLY LIGHTFOOD CRAB (Graspus graspus)

Pronounced:

grass-pus grass-pus

Order:

Malacostraca

Kingdom:

Animalia

Family:

Grapsidae

Phylum:

Arthropoda

Genus:

Graspus

Class:

Crustacea

Species:

Graspus

As light on its toes as its name suggest, Sally Lightfoot can be seen dashing to the shoreline as waves recede, where she (or he) checks for algae, dead pieces of sea life, or anything else to eat. When the next wave approaches, she’s off again, heading for nearby rocks where she will hunker down until the wave has passed and she can rush out again in her exhaustive search for food.

Lightfoot crabs can be found on beaches from Florida to Mexico, south to Peru and Brazil, as well as in the Galapagos Islands. They spend most of their time hiding in rock crevices, but when they’re not hiding, chances are they’re dancing amongst the waves searching for prey. Sometimes they fall prey, themselves, to a variety of wildlife, from birds to sea turtles and the Chain Moray Eel (which can survive for a while outside of the water).

Lightfoot crabs begin life as zoea larvae. They will molt several times before becoming adults and will continue to grow their entire lives, although the length of time between molts will grow greater with time. When young, their colors are black or green, but they become bright red and orange with yellow markings as adults. They grow to be about 7 cm wide in most locations. Females lay eggs which are carried on her abdomen until they hatch. The mother helps them hatch by shaking her abdomen and using her chelae to break the egg sack. They often hatch either during a full or new moon.

Crabs are arthropods, like insects, spiders and centipedes. But they also have gills. Sally Lightfoot gets her oxygen through these gills as she dashes through the waves. She also keeps a supply of water inside her carapace which she can splash over her gills if she’s been out of the water for too long. Some reports say they can also use this water reservoir to squirt water at their predators in defense.

Sally is incredibly fast and also has excellent eyesight. In addition, she has the ability to regrow limbs that have been snapped off by predators. And, of course, her carapace protects her as well.