Kingdom Animalia
Phylum Anthropoda
Subphylum Crustacea
Class Malacostraca
Order Decapoda
Suborder Pleocyemata
Infraorder Anomura
Superfamily Paguroidea
Family Coenobitidae
Genus Birgus
Species B. latro

An enormous, repulsive crab.

The robber crab is the biggest land crab on Earth. If it got much bigger it'd fall apart under its own weight. Of course, put something underwater and gravity grants a reprieve. Ocean-dwelling Japanese spider crabs are thirteen feet across. Last time I checked, that's about the size of a pickup.

Thankfully, robber crabs are only three feet.

So why "robber crab?"

They're known to wander into homes and steal cookware.

Its alternate name, coconut crab, refers to its favorite food. The legs of a robber crab are tipped with useful, tweezer-like chelae that allow it to climb trees and retreive coconuts, which it cracks open with its tremendous pincers. For its nine pounds, the robber crab is a herculean little beast — with each arm it can lift and carry some 64 pounds. Human powerlifters dream fondly of lifing eight times their own weight one-handed.

The robber crab is an unsightly thing. A marriage of spider and lobster. Like all decapods, it's got ten legs flaring out from the beefed-up thorax. This creature is somewhat front-heavy, with a sad, puckery-looking little abdomen. In its youth the robber crab protects its body with found shells, like a hermit crab. Young adults will shield themselves with coconut shell fragments. Adulthood sees the development of a chitin and chalk shell, which is molted periodically.

Robber crabs can smell rot from quite a distance.

While their favorite food is coconuts, they'll feast on nearly anything organic. Fresh fruit, rotten fruit, dead animals, abandoned shells, leaves, and other members of the species are all on the robber crab's menu. Food is found with an unusual nose, made similar to that of an insect through convergent evolution. It also has the rare talent of detecting odors in both water and air, residues of ancient lives under the waves. But make no mistake: the robber crab is strictly a land-dweller. While its lungs are able to function as rudimentary gills, it will drown if submerged long enough.

The robber crab lives a long time: thirty to sixty years. Mating is a sweet affair — violent fighting on the sand followed by the male ejaculating into the female he's managed to flip over. Mating is a frequent act between May and September.

Once inseminated, the female makes her way to the low tide and deposits her eggs in the surf, where they float for about a month. Most of the embryos are digested by predators; those that hatch are planktonic, settling on the ocean floor and taking up the life of a hermit crab for another month. Once it's mature enough, it climbs up on the beach and loses its ability to breathe in water.

Robber crabs are nocturnal, spending their days staying moist in the burrows they dig in the sand. Daytime activity is limited to rainy days and densely populated habitats, where individuals will emerge early to earn claim on the food. Geographically, they're distributed throughout the Indian and Pacific Oceans, with the earth's largest population concentrated on Christmas Island.

Robber crabs are disgusting, intimidating creatures. They also make an excellent delicacy.

Hunters typically take to the chase at night with flashlights. Supposedly, filling the beaches with smoked coconut shells attracts crabs. Their taste is said to be a mix between lobster and crab, and they're purported to be an aphrodisiac. The female's eggs are the most sought-after product.

They're cooked like lobsters — boiled or steamed. Some prefer boiling them in coconut milk. While robber crabs aren't inherently toxic, they can become poisonous by consuming toxic substances. Robber crab poisoning is not unheard of.

Supposedly, robber crabs are used to protect coconut plantations because they attack people.