Main Content

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Ref ID : 4774

Hans-Jurgen Voss; [Vergleichende morphogenetische Untersuchung von 13 Arten der Gattung Euplotes (Ciliophora, Hypotrichida)] (Morphogenetic Comparison of 13 species of the Genus Euplotes (Ciliophora, Hypotrichida)). Arch.Protistenk 137:331-344, 1989

Reprint

In File

Notes

The morphogenesis of 13 species of the genus Euplotes (E. aediculatus, E. charon, E. crassus, E. daidaleos, E. eurystomus, E. minuta, E. octocarinatus, E. patella, E. raikovi, E. rariseta, E. vannus, E. finki and E. woodruffi) was investigated in the exception to use morphogenetic criteria for discrimination of species. Six stages of the division process which occur during cortical and nuclear fission were analysed and compared. The morphogenetic events are very similar in all examined species. Thus, they can not be used to discriminate species. The morphogenesis starts with a proliferation of the basal bodies for the oral primordium closely behind the adoral zone of membranelles of the parental cell. From the developing oral primordium evolve the adoral membranelles and the paroral membrane of the opisthe. The frontoventral and transverse cirri differentiate from anterior and posterior sets each of 5 kinetosomal streaks (Anlagen I-V). Within ciliary outgrowth in cirrotype-9-species a 3:3:3:2:2 pattern of cirral fields is found; in cirrotype-10-species the new cirri develop in the ratio 3:3:3:3:2 always from left to right across the fields of the anterior and posterior sets. The development of the dorsal kineties proceeds according to type 7 and shows no special features. New left caudal cirri for the anterior and posterior daughter cell generate from small linear arrangements of basal bodies on the ventral surface between the developing membranellar band and the left cell margin. On the other hand, the new right caudal cirri develop within the two last kineties on the dorsal surface: for the proter at a level just anterior to the prospective fission line and for the opisthe at the posterior ends of the kineties. The parental adoral membranelles and the paroral membrane are not dedifferentiated during the whole process of morphogenesis, but the parental cirri are completely resorbed.