ILPLA   05424
INSTITUTO DE LIMNOLOGIA "DR. RAUL A. RINGUELET"
Unidad Ejecutora - UE
artículos
Título:
An Antarctic hypotrichous ciliate, Parasterkiella thompsoni (Foissner) nov. gen., nov. comb., from Argentinean peat-bogs: morphology, morphogenesis, and molecular phylogeny
Autor/es:
KÜPPERS G. C.; DA SILVA PAIVA T.; DO NASCIMENTO BORGES B.; HARADA M. L.; GONZÁLEZ GARRAZA G.; MATALONI G.
Revista:
EUROPEAN JOURNAL OF PROTISTOLOGY
Editorial:
ELSEVIER GMBH
Referencias:
Año: 2011 vol. 47 p. 103 - 103
ISSN:
0932-4739
Resumen:
The ciliate Parasterkiella thompsoni (Foissner, 1996) nov. gen., nov. comb. was originally described from Antarctica. In the present study, we report the morphology, morphogenesis during cell division, and molecular phylogeny inferred from the 18S-rDNA sequence of a population isolated from the Rancho Hambre peat bog, Tierra del Fuego Province, Argentina. The study is based on live and protargol-impregnated specimens. Molecular phylogeny was inferred from trees constructed by means of the maximum parsimony, neighbor joining, and Bayesian analyses. The interphase morphology matches the original description of the species. During the cell division, stomatogenesis begins with the de novo proliferation of two fields of basal bodies, each one left of the postoral ventral cirri and of transverse cirri, which fields later unify. Primordia IV–VI of the proter develop from disaggregation of cirrus IV/3, while primordium IV of the opisthe develops from cirrus IV/2 and primordia V and VI from cirrus V/4. Dorsal morphogenesis occurs in the Urosomoida pattern—that is, the fragmentation of kinety 3 is lacking. Three macronuclear nodules are generated before cytokinesis. Phylogenetic analyses consistently placed P. thompsoni within the stylonychines. New data on the morphogenesis of the dorsal ciliature justifies the transference of Sterkiella thompsoni to a new genus, Parasterkiella.