MORPHOLOGY AND ULTRASTRUCTURE OF THE CILIATE CONDYLOSTOMIDES-GROLIERI GEN-N, SP-N (CILIOPHORA, HETEROTRICHIDA)

The non-contractile ciliate Condylostomides grolieri gen. n., sp. n. inhabiting calcium carbonate-mineral springs, shows a dikinetid based-somatic ultrastructure, typical for Heterotrichs. The anterior kinetosome of each dikinetid is ciliferous and is associated with a ribbon of 13-15 transverse microtubules (T1), with 2 additional microtubules (T2) at the level of the triplet 5 zone. The posterior kinetosome is naked, associated with 2 transverse microtubules in the triplets 4-5 zone, a catedodesmal striated fibre directed towards the right, perpendicularly to the kinety in the triplets 5-6 zone, a ribbon of postciliary microtubules which is accompaned at the right by a retrodesmal strip and at the left by a retrodesmal fibre showing a periodical structure. This latter represents the original characteristic of Condylostomides cortex. The structure of buccal organelles resembles that observed in Fabrea, Phacodinium and Copemetopus. Each adoral organelle bears three rows of kinetosomes. The right row-kinetosomes show a ribbon of postciliary fibres. The kinetosomes located on the left row have a ribbon of transverse doubled microtubules with an additional single microtubule, present on all other nematodesma bearing-kinetosomes of the organelle. The paroral organelle consists of a double row of kinetosomes with, on the one hand, ribbons of postciliary microtubules associated with kinetosomes of the external row and, on the other hand, a transverse microtubule associated with kinetosomes of the internal row. Over the anterior course of the paroral, and through an irregular arrangement, the kinetosomes of the internal row can be perpendicular one to another. Moreover, the anterior third of the paroral is doubled by the kinetofragments of 4 kinetosomes which all bear postciliary microtubules, a transverse microtubule and nematodesma.