A DIGITAL HOLOGRAPHIC STUDY OF THE SWIMMING CHARACTERISTICS OF PROROCENTRUM MINIMUM (DINOPHYCEAE)

摘要

Most dinoflagellates are unicellular and usually have two flagella. One flagellum is the longitudinal one which extends towards the posterior and the other is the transverse one which encircles the body ventrally. The role and mechanism of the longitudinal and transverse flagella in the swimming of dinoflagellates is species-dependent and sometimes controversial. The present study investigated the swimming characteristics of Prorocentrum minimum, which is one of the cosmopolitan dinoflagellate species causing red tides. A digital holographic PTV technique was employed to get the swimming trajectories of hundreds of P. minimum cells and to extract the kinematics of the flagella beating motion. The average swimming speed of P. minimum cells (n=270) in a helical motion was about 90±60μm/sec. The longitudinal flagellum beaten with a planar wave and the transverse flagellum beaten with a helical wave.