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).
In general terms, male salamanders with external fertilization (i.e., the Cryptobranchidae, Hynobiidae, and Sirenidae) have few or no cloacal glands whereas salamanders with internal fertilization (all other salamanders; i.e., Salamandroidea) have abundant cloacal glands.
The major difference between the two topologies was the recovery of the Sirenidae as the basal salamander lineage (results in a monophyletic Salamandroidea; Wiens et al., 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 ?
CLASS AMPHIBIA Order Caudata (salamanders) Family Cryptobranchidae
(hellbenders) Crytobranchus alleganiensis (Daudin) hellbender S Family Proteidae (mudpuppies) Necturus macidosus (Rafinesque), mudpuppy I Family Ambystomatidae (mole salamanders) Ambystoma barbouri Kraus & Petranka, streamside SE salamander A.