Abstract
A new species of spider crab, Hemus magalae n. sp. (Majidae), is described from a single male specimen from Islas de las Perlas, Pacific Ocean coast of Panama. This species differs from its congeners with respect to many features of the carapace including mid-line elevation and lateral dentition. Hemus A. Milne-Edwards, 1875, now includes four species, three from coastal waters of the eastern Pacific Ocean and one from shallow waters in the tropical western Atlantic Ocean. A key to the Pacific and Atlantic species of Hemus is provided.