Morphology and infraciliature of some soil ciliates (Protozoa, Ciliophora) from continental Antarctica, with notes on the morphogenesis of Sterkiella histriomuscorum

Abstract

AbstractThe morphology of seven soil ciliate species from continental Antarctica was investigated using live observation and protargol impregnation. Observations on two populations of Protospathidium serpens corroborate the view that this species usually has a single, more-or-less nodular, macronucleus distinguishing it from P. muscicola, which possesses 10–30 nodules. The Antarctic specimens of Protospathidium terricola differ inconspicuously from the type population in that they are slightly larger, have fewer ciliary rows (17 vs 21), and the fragments of the circumoral kinety are less distinctly separated from each other. Spathidium seppelti nov. spec, resembles 5. bavariense, but has 100–200 macronuclear nodules and a conical depression in the dorsal third of the oral bulge. Odontochlamys wisconsinensis nov. comb, (basionym: Chilodonella wisconsinensis Kahl, 1931) has four right field kineties and an oral basket consisting of 14 rods; the dorsal brush is near the anterior margin and usually consists of four cilia. The Antarctic population of Pseudochilodonopsis mutabilis possesses a regular dorsal hump and only 12–14 (about 15 in Austrian type population) phary ngeal rods. Oxytricha opisthomuscorum has six dorsal kineties with long cilia and a buccal cirrus near the anterior end of the paroral membrane. The Antarctic specimens of Sterkiella histriomuscorum have fïve transverse cirri. Their morphogenesis differs slightly from that of a population having four transverse cirri in that the daughter's anlagen are more distinctly separated and some temporal sequences are different.