Land crabs are always interesting – they are obvious, often quite large and sometimes edible. Until the 1990s, one of the least understood land crabs was a species everyone was calling Cardisoma longipes. Supposedly described from New Caledonia, scientists never found the species there. It had been seen in some other small Pacific islands but never common. Things moved fast in the late 1990s when the species was better understood – they like karst formations, living in the vegetation, and are nocturnal. The reason why they were never found on New Caledonia was that the original label was wrong. They were common in the nearby Loyalty Islands – which are karsts! A French expedition deep into the caves found them in good numbers! More were then found in Guam and then Vanuatu. To make the story even more interesting, in a joint study, French and Singapore researchers named a new allied species from karst caves in the Philippines, and showed that the genus Discoplax – erected by Alphonse Milne-Edwards in 1867 – but sunk under Cardisoma by workers for decades – was in fact a good genus!