There are two new vampire crabs being added to the roster, and yes, there is really a roster of vampire crabs. What's unusual about these new discoveries, however, is that while they are new to science, they have been residents of some home aquariums for a pretty long time.

The crabs, as described in a recent report in the Raffles Bulletin of Zoology, are Geosesarma dennerle and Geosesarma hagen, and if spotted in low light, they may very much look like a pair of vampires sizing up their next meal. That's because like most vampire crabs, these crabs have bright yellow eyes that contrast the ducky blues, grays, brows, or purples of their shell. They also hold their small and vibrantly colored claws close to their bodies, making them almost look like a pair of bloody fangs.

This description serves best for G. hagen. which has bright red (sometimes orange) claws, wide-yellow eyes, and a shell that is almost always deep purple. G. dennerle, on the other hand, looks like a vampire with a love for all things grape, as its claws are a bright violet (almost pink) that starkly contrast its dusky shell.

Both, but most commonly the latter of these two, are referred to as "purple vampire crabs" and are surprisingly popular exotic pets among personal freshwater aquarium owners. ( Scroll to read on...)

Peter Ng from the Lee Kong Chian Natural History Museum in Singapore, and German researchers Christophe Schubart and Christian Lukhaup, recently pooled efforts to finally classify these intriguing pets. According to the team, the animals have been circulating in the oriental and European pet trade for the greater part of the last decade, but had never been officially recognized. For the most part, experts didn't even know from where these unusual crabs originated.

That's why the trio was lucky to find wild examples of the crabs only about six miles from each other along a system of hillstreams in central Java.

According to National Geographic, Lukhaup was born in Transylvania, home to the mythical Dracula, and the irony was not lost when it was he who first stumbled upon the crabs.

They told National Geographic that he had finally found the crabs after calling in favors and following a lot of false leads. Apparently the pet crab trade can get pretty cutthroat, and the true locations of the crabs' native habitats was a well-kept secret.

The crabs, as it turns out, are largely terrestrial, explaining for their vibrant hues. On land, color, rather than chemical release, is often a powerful means of communication - whether it be for warning, sex appeal, or something else entirely.

Schubart now suspects that there are many more vampire crabs just waiting to be found around the Indonesian islands, and with the help of his 'vampire hunter' colleague, he intends to keep looking.

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