A new species of Coronarctus (Tardigrada, Heterotardigrada) in the deep sea from the Gulf of Mexico revealed by geometric morphometrics and an updated genus key

Abstract Coronarctus Renaud-Mornant, 1974, is currently composed of eleven species, which are found in deep sea and shallow environments. We described a new species of Coronarctus , as well as doing a morphometric analysis and providing an identification key, from specimens collected in deep-sea sediments (1,182–2,822 m) in the southern Gulf of Mexico. Corononarctus xiximii sp. nov. is characterized by spherical primary clavae and flattened secondary clavae, each with two dorsal and two ventral lobes; sensory organs on each pair of legs and additional flexible spine-like processes on legs IV, and heteromorphic, simple claws, with the internal claw of leg IV being twice the size of the external claws. This discovery increases the number of Coronarctus species worldwide to twelve.