A new species of Tardigrada (Eutardigrada), Calcarobiotus longinoi sp. nov., is described from moss samples collected in Alajuela Province (Costa Rica). The presence of genus Calcarobiotus is new for Central America. This species differs from other species of the genus Calcarobiotus by lacking of spurs on the basal portion of the claws. On the base of this new finding, the diagnosis of the subgenus Calcarobiotus is emended. A taxonomic key to the genus Calcarobiotus is also presented.