Bidder's organ in the female of Bufo ictericus: Morphological characterization

Abstract

Bidder's organ has been cited as a structure present only in males of the toad family Bufonidae, and is used as a systematic characteristic. In this study, we examined females of Bufo ictericus in order to ascertain whether this structure also occurs in females. Macroscopic observations and light microscopy technique for paraffin embedding were performed. This study reveals that females of Bufo ictericus can have a Bidder's organ with typical morphology, and in close spatial relationship with the ovary. This suggests that the Bidder's organ is not an exclusive structure for male toads, but that it may also occur in active females.