The specific name vocans has priority from Linnaeus (1758), although he adopted the name from Rumphius (1705).
As the original taxonomic name applied to fiddler crabs, vocans was widely used for all species in the last 18th and early 19th centuries, leading to a lot of taxonomic confusion. In the late 19th and early 20th centuries, many authors suggested abandoning the name entirely due to its earlier ambiguity, but eventually its priority took hold.