1 Rhvacotritonidae 1 0 1 1 0 0 Cryptobranchidae 1 0 1 1 ?
Collecting ducts that do not communicate along the length of the Wolffian ducts adjacent to the pelvic kidneys (character 1, state 1) evolved either once on the branch leading to all salamanders, excluding the Sirenidae (with secondary loss in the Proteidae; character 1, state 0), or evolved independently on the branches leading to the Cryptobranchidae + Hynobiidae and the Salamandroidea excluding the Proteidae.
However, collecting ducts that do not communicate with the Wolffian ducts along their lengths traveling adjacent to the pelvic kidney (character 1, state 1) were recovered as the ancestral state for the Cryptobranchidae + Hynobiidae and all other salamander excluding the Proteidae and Sirenidae.
The Cryptobranchidae + Hynobiidae, Ambystomatidae Dicamptodontidae + Salamandridae, and Proteidae lineages possess a Bidder's duct, while this characteristic is lacking on the branches leading to the Sirenidae and Amphiumidae + Plethodontidae + Rhyacotritonidae.
The ancestral state for all salamanders excluding the Cryptobranchidae + Hynobiidae could not be recovered for this character, and thus, it cannot be unequivocally confirmed that the Proteidae evolved posterior ventral glands independently or if the Sirenidae lost these glands.