Female reproductive tract of the lesser anteater (Tamandua tetradactyla, Myrmecophagidae, Xenarthra). Anatomy and histology.

L. ROSSI; J. P. LUACES; H. ALDANA MARCOS; P. CETICA; G. GACHEN; G. PÉREZ JIMENO; M. S. MERANI

JOURNAL OF MORPHOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Año: 2011 vol. 272 p. 1307 - 1313

0362-2525

The morphological an histological features of the unusual reproductive tract of the female lesser anteater, Tamandua tetradacryla (Myrmecophagidae Xenarthra), are described for the first time. The present study aimed to establish the main similarities and differences between this species and other xenartrans. The population of this species are declining rapidly for a number of reasons and our study is relevant to diverse programs related to its conservation. Studies were carried out on five female genital tracts of adult specimens. Ovaries from ovoid, presenting a medulla completely surrounded by the cortex, differently from that described in other xenerthans. As it happens in the genus Dasypus and unlike the rest of the armadillos studied, single oocyte follicles were observed. The uterus is simple, like that of Myrmecophaga tridactyla and the armadillos of the genus Dasypus and unlike the rest of the armadillos studied, which have a bicornuate uterus. The uterovaginal canal connects the body of the uterus with the urogenital sinus. The simple columnar epithelium of the uterovaginal canal ends abruptly at a septum, which resembles a hymen, where the transitional epithelium of the urogenital sinus appears. This primitive structure is shared with that of other armadillos, with the exception of Tolypeutes matacus, which has a true vagina. Characteristics of the reproductive tract and sperm morphology of other Xenarthrare comparatively discussed. These observations suggest that important reproductive features are share between the family Myrmecophagidae and the genus Dasypus, a basal group in the phylogeny of Xenarthra.