Spermatogenesis in several intra- and interspecific hybrids of the lemur (Lemur)

Spermatogenesis of various hybrids of the genus Lemur was studied by testicular biopsy. In hybrids between species whose classification is still much debated, the germinal cells had degenerated after the pachytene stage. This abnormality was variable in intensity depending on the parents mating: L. fulvus (2N = 60) subspecies x L. macaco sometimes resulted in fertile offspring while L. fulvus collaris x L. macaco never did. We believe that the defect in spermatogenesis is mostly caused by differences in meiotic behaviour in the germinal cells. In hybrids between two species for which there is not taxonomic doubt (L. fulvus x L. rubriventer), the gonads were completely devoid of germ cells.