in all other salamanders the collecting ducts bend caudally during development (Rodgers and Risley, 1938) and either anastomose and enter the cloaca (in the Plethodontidae and some Salamandridae; Francis, 1934; Baker, 1965; Strickland, 1966), anastomose and enter Wolthan ducts (in the Ambystomatidae, Amphiumidae, and some Salamandridae, Baker, 1945; Baker and Taylor, 1964; Baker, 1965), or enter the cloaca individually (in the Cryptobranchidae and Hynobiidae; Ratcliff, 1965; Yamagiwa, 1924).
the Cryptobranchidae, Hynobiidae, and Sirenidae) have few or no cloacal glands whereas salamanders with internal fertilization (all other salamanders; i.
2005) or the recovery of the Cryptobranchidae + Hynobiidae clade as the basal salamander lineage and the Sirenidae as the sister taxon to Proteidae (results in a paraphyletic Salamandroidea; Struck, 2007).
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.