Abstract
Planktonic ciliates below sea ice in Franklin Bay, Canada were studied in terms of their taxonomic composition and species descriptions. They occurred at an abundance of 2,400 cells L−1 and a biovolume of 4.24×106 μm3 L−1. Loricate ciliates (Tintinnida, Spirotrichea) occupied a very small percentage of the total both in terms of abundance (1.7%) and biovolume (1.9%). On the other hand, aloricate ciliates were predominant; in particular Myrionecta rubra (Cyclotrichida, Litostomatea) in terms of abundance (50%) and Lohmaniella oviformis (Choreotrichida, Spirotrichea) in terms of biomass (19.2%). Diagnoses and descriptions are given for ten aloricate species; eight of these species (Leegaardiella ovalis, Lohmaniella oviformis, Tontonia gracillima, Strombidium acutum, S. constrictum, S. dalum, S. epidemum, Myrionecta rubra) were identifiable in the present material. Compared with previous descriptions, six of these species (not S. constrictum or M. rubra) have more or less distinct characters incompatible with reported intraspecific variations.
