Bursellopsis spaniopogon n. spec. (Ciliophora: Prostomatida) : I. Infraciliature and ultrastructure of the somatic and oral cortex

Abstract

A description is given of a new species of the genus Bursellopsis Corliss, 1960. Its infraciliature is studied by means of Klein's dry silver technique and Fernández-Galiano's pyridinated silver-carbonate-method. The light microscopical results are supplemented by a comparative scanning and transmission electron microscope study, with special reference to the somatic cortex, the circum-oral ciliature, and the "dorsal brush". The kineties of the somatic cortex, consisting of monokinetids, cover only the anterior four fifths of the cell. Three fibrillar systems, a kinetodesmal fibre, a postciliary microtubular ribbon, a transverse microtubular ribbon and one parasomal sac are associated with each monokinetid. The circum-oral kinety consists of dikinetids bearing only stubs of cilia. The so-called "dorsal brush" consists of dikinetids, with only their anterior kinetosomes bearing "brush cilia", which are shorter than the somatic cilia. The biometric data of Bursellopsis spaniopogon are given and the ultrastructure of the new species is compared to light microscopical and ultrastructural data of Urotricha, Holopbrya and Prorodon. The systematic position of the genus Bursellopsis is discussed and an improved diagnosis of Bursellopsis is provided.