Ref ID : 1046
Helga Muller; Pseudobalanion planctonicum (Ciliophora, Prostomatida): ecological significance of an algivorous nanociliate in a deep meso-eutrophic lake. J.Plankton Research 13(1):247-262, 1991
Reprint
In File
Notes
Pseudobalanion planctonicum was the most abundant ciliate species in the pelagic zone of Lake Constance, FRG, over a 3 year period. Annual averages accounted for 30, 35 and 43% of total ciliate numbers in the uppermost 20 m of the water column in 1987, 1988 and 1989 respectively. Highest cell numbers were observed in early spring, simultaneously with the first phytoplankton maximum. The small ciliate (mean length 15 um, mean cell volume 1300 um3) is a raptorial feeder and predominantly consumes phytoplankton. In laboratory cultures, P. planctonicum grew well on a diet of Rhodomonas sp. (Cryptophyceae). Maximum growth rates increased from 0.46 day-1 at 5.5 degrees C to 1.52 day-1 at 18.5 degrees C, while temperature above 21 degrees C were lethal. Depending on food concentration, 0.2-4.4 Rhodomonas cells were ingested per ciliate and hour.