Tailed frogs are unique among the anurans in exhibiting a combination of amplexus and copulation during courtship and mating. Courtship occurs at the onset of fall, between September and October, and is carried out in the water. During courtship, a male typically lunges or swims suddenly toward a female of the same species. Clasping the female’s body directly anterior to her pelvic region, the male may then perform either inguinal or ventral amplexus. Once in the proper position, copulation can follow, the male's erect “tail” inserted into the female’s cloaca. To press closer to the female during copulation, the male may repeatedly produce thrusts of his pelvic region, his “tail” still within the cloaca.
Mating System: polygynous
Tailed frog females have been shown to reproduce biennially, while males may mate annually. This behavior may vary geographically. Although courtship and mating occur in the fall, tailed frog females store the sperm and do not deposit eggs until June or July. When deposition finally takes places, a dual strand of 44 to 85 small-sized eggs is fixed to the base of a rock or boulder within the stream system. After approximately six weeks, hatchlings then appear. The tadpole or larval stage may last anywhere from one to four years, geographic location likely impacts the length. Coastal populations spend 1 to 3 years in the larval state, whereas montane or inland populations spend 3 to 4 years. Tailed frog tadpoles undergo metamorphosis, which includes absorbing their tails, developing an adult mouth, losing the suction mouth, and developing legs. A juvenile may not reach reproductive maturity until it is 2 to 8 years old, varying geographically.
Breeding interval: Tailed frog females breed biennially, while males may breed annually.
Breeding season: Tailed frogs breed from September through October (fertilization) and females lay eggs from June to July (oviposition).
Range number of offspring: 44 to 85.
Average time to hatching: 6 weeks.
Range age at sexual or reproductive maturity (female): 2.5 to 4 years.
Average age at sexual or reproductive maturity (female): 3 years.
Range age at sexual or reproductive maturity (male): 1.5 to 4 years.
Average age at sexual or reproductive maturity (male): 3 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous ; sperm-storing
There is little available information on parental care in Ascaphus truei.