What is "heloecius"

Heloecius cordiformis is a species of semiterrestrial crab found in mangrove swamps and mudflats along the east coast of Australia. Adults are around wide, with males being larger and having larger and more conspicuously coloured claws. The males wave their claws to communicate with other crabs, giving them their common name of semaphore crab. They can breathe both in air and under water, and feed at low tide on detritus in the sediment. H. cordiformis is the only species in the genus Heloecius and the family Heloeciidae.