Comparative Spermatology in Dasypodidae II (Chaetophractus vellerosus, Zaedyus pichiy, Euphactus sexcinctus, Tolypeutes matacus, Dasypus septemcinctus & Dasypus novemcinctus)

P. CETICA, I.M. RAHN, M.S. MERANI AND A. SOLARI

BIOCELL

IHEM-CONICET

Año: 1997 vol. 21 p. 195 - 204

0327-9545

At present there is increasing interest in the phylogeny and evolution of reproductive systems. Comparative sperm morphology and relationships of spermatozoa sizes ha ve been studied in Chaetophractus vellerosus (lesser hairy or crying armadillo), Zaedyus pichiy (pichi), Eluphractus sexcinctus (yellow armadillo), Tolypeutes matacus (Azara´s domed armadillo). Dasypus septemcinculs (seven-banded long-nosed armadillo) and Dasypus novemcinctus (nine-banded long-nosed armadillo) (Dasypodidae). The spermatozoa were observed in phase contrast microscopy and their linear dimensions were measured from Giemsa and silver stained spreads. Fine structure of the spermatozoa were also studied. The sperm heads in Ch. v´ellerosus, Z. pichiy and E. sexcinctus are very large in the frontal view and flattened in the profile one. Electron microscopy confirmed their slim heads. T. matacus sperm head presents a characteristic laterocaudal nuclear extension. D. septemcinctus and D. novemcinctus spematozoa are similar to those of the other eutherians. These results and their comparisons with spematozoa of armadillos suggest that sperm shape and size are not constant across taxa in Dasypodidae.