Glow Crab

The glow crab, also known as the happy crab or the molly crab, is a species of terrestrial hermit crab, related to the coconut crab. Overall, they behave and look like regular coconut crabs. The body of the glow crab is, like that of all decapods, divided into a front section (cephalothorax), which has 10 legs, and an abdomen. The front-most pair of legs have large chelae (claws), with the left being larger than the right. The next two pairs, as with other hermit crabs, are large, powerful walking legs with pointed tips, which allow glow crabs to climb vertical or overhanging surfaces. The key difference that differentiates them from other decapods is their bioluminescent properties. Their entire exoskeleton glows in psychedelic patterns that produces a soft glow, usually in pleasant shades of pink, aqua, teal, cyan, green, and yellow.

Glow crabs mate frequently and quickly on dry land in the period from May to September, especially between early June and late August. Males have spermatophores and deposit a mass of spermatophores on the abdomens of females; the oviducts opens at the base of the third pereiopods, and fertilisation is thought to occur on the external surface of the abdomen, as the eggs pass through the spermatophore mass. The extrusion of eggs occurs on land in crevices or burrows near the shore. The female lays her eggs shortly after mating and glues them to the underside of her abdomen, carrying the fertilised eggs underneath her body for a few months. At the time of hatching, the female glow crab migrates to the seashore and releases the larvae into the ocean. The glow crab takes a large risk while laying the eggs, because glow crabs cannot swim: If a glow crab falls into the water or is swept away, its weight makes it difficult, or impossible, for it to swim back to dry land. The egg laying usually takes place on rocky shores at dusk, especially when this coincides with high tide. The empty egg cases remain on the female's body after the larvae have been released, and the female eats the egg cases within a few days.

The larvae float in the pelagic zone of the ocean with other plankton for 3–4 weeks, during which a large number of them are eaten by predators. The larvae pass through three to five zoea stages before moulting into the postlarval glaucothoe stage; this process takes from 25 to 33 days. Upon reaching the glaucothoe stage of development, they settle to the bottom, find and wear a suitably sized gastropod shell, and migrate to the shoreline with other terrestrial hermit crabs. At that time, they sometimes visit dry land. Afterwards, they leave the ocean permanently and lose the ability to breathe in water. As with all hermit crabs, they change their shells as they grow. Young glow crabs that cannot find a seashell of the right size often use broken coconut pieces. When they outgrow their shells, they develop a hardened abdomen. The glow crab reaches sexual maturity around 5 years after hatching. They reach their maximum size only after 40–60 years

Glow crabs are considered one of the most terrestrial-adapted of the decapods, with most aspects of its life oriented to, and centered around such an existence; they will actually drown in sea water in less than a day. Glow crabs live alone in burrows and rock crevices in the wild, and commonly take shelter in crevices and broken pipes in the Trench. They dig their own burrows in sand or loose soil. During the day, the animal stays hidden to reduce water loss from heat. The glow crabs' burrows contain very fine yet strong fibres of the coconut husk which the animal uses as bedding. While resting in its burrow, the glow crab closes the entrances with one of its claws to create the moist microclimate within the burrow, which is necessary for the functioning of its breathing organs.

The diet of glowcrabs consists primarily of fleshy fruits, nuts, drupes, and seeds, and the pith of fallen trees. However, as they are omnivores, they will consume other organic materials such as tortoise hatchlings in the wild, and small monsters and vermin like rats in the Trench, and dead animals. They have been observed to prey upon crabs such as Gecarcoidea natalis and Discoplax hirtipes, as well as scavenge on the carcasses of other glow crabs.

Based on their physical description, glow crabs might not seem strange or dangerous enough to warrant their imprisonment in the Trench, right? Well, the anomalous properties that led to them being taken and studied by the Organization come around when an organism of other species get close to them. Upon reaching a radius of about 16 feet(4.8 meters) any organism nearby will begin to experience the following symptoms;

• Euphoria – a sense of general well-being and happiness.

• Increased self-confidence, sociability, and perception of facilitated communication.

• Entactogenic effects—increased empathy or feelings of closeness with others and oneself.

• Relaxation and reduced anxiety.

• Increased emotionality, a sense of inner peace,

• Mild hallucination.

• Enhanced sensation, perception, or sexuality

• An altered sense of time.

All of which are symptoms of those who use methylenedioxymethamphetamine (MDMA), commonly known as ecstasy. However, the glowcrab does not replicate any of negative effects of the drug. This is believed to have evolved as a way to both avoid predation and accquire prey by making the would-be predator or prey too high to react to the crab's actions. At first, this ability was believed to be caused by pheramonal factors or by visual contact with the glow of the crab's shell. But Organization testing has dismissed both these theories and instead theorized that the crab's abilities are telepathic in nature.

While glow crab meat can be cooked and eaten. The creatures are more valuable alive than dead. Because they can essentially produce the effects of ecstasy without any of the drawbacks, glow crabs are highly sought after in the Trench's black market. This has led to the rise of crab dens. Speakeasy-like establishments where patrons pay to recreationally enjoy the creatures' psychedelic effects as much as they like.

Glow crabs have a well-developed sense of smell, which it uses to locate its food. The process of smelling works very differently depending on whether the smelled molecules are hydrophilic molecules in water or hydrophobic molecules in air. Crabs that live in water have specialized organs called aesthetascs on their antennae to determine both the denseness and the direction of a scent. Glow crabs live on the land, so the aesthetascs on their antennae are shorter and blunter than those of other crabs and are more similar to those of insects.