MICROTUBULAR ELEMENTS OF THE MARINE ANTARCTIC CILIATE EUPLOTES FOCARDII (CILIOPHORA, HYPOTRICHIA)

Microtubules are the major cytoskeletal component in Euplotes focardii The spatial organization of the microtubular system of this marine antarctic ciliate is described. Three different methods were employed: immunofluorescence using antitubulin antibodies, scanning electron microscopy, and transmission electron microscopy. The general arrangement of the cytoskeletal microtubular system is similar to that described for temperate species of Euplotes. Basal bodies, microtubular derivatives associated with the kinetosomes and superficial microtubular networks in both dorsal and ventral sides are stable at the low temperatures this species must bear. Slight differences are reported in the disposition of the microtubules on the somatic cortex. As for the oral cytoskeleton the left side infraciliature is reinforced by a complex microtubular system: on the one hand, a developed microtubular network spreading under and among the paramembranelles, and on the other hand microtubules reinforcing the oral crests.