Redescription of the sibling species plesionika acanthonotus (Smith, 1882) and plesionika holthuisi Crosnier & Forest, 1968 (caridea, pandalidae)

Abstract

The Brazilian expedition REVIZEE Central - Fishery collected samples from the southwestern Atlantic coast, between depths of 200 and 2200m. This expedition sampled two very similar species of Plesionika Bate, 1888: Plesionika acanthonotus (Smith, 1882) and Plesionika holthuisi Crosnier & Forest, 1968. These sibling species differs in the rostrum length, eyes size, length of third maxilliped, and number of stout setae on third and fourth pereopods. Some specimens can be clearly identified but in many specimens this identification becomes very problematic once these characters appear in intermediate stages between both species. The Brazilian material of these two species was redescribed and compared with the material deposited on Muséum National d´Histoire Naturelle collection. Besides that, a discussion about the relations and similarities of these species was done.