(A) An adult male just after emerging from a breeding pond (early April). A tubercle (expressed by "t") is discernible at the anterior angle of the vent. The tubercle, as well as the cloacal region, is more swelling in a typical aquatic-phase male. The tubercle is evident in adult males throughout the year except from May-July when ventral glands are underdeveloped (Hasumi et al., 1990).

(B) An adult female in a preovulatory condition just before entering a breeding pond (mid-March). A tubercle is always lacking in adult females (Hasumi, 1996).

*In general, a tubercle at the anterior angle of the vent is seen in breeding males of lentic-breeding hynobiid salamanders (Sato, 1943). Although Salamandrella keyserlingii appears to have morphological characteristics of lentic-breeding hynobiids, males lack this tubercle (Hasumi, 2001).

Sato, I. 1943. Monograph of Japanese Tailed Batrachians. Nippon Shuppan-sha, Osaka, Japan. (In Japanese)