The First Successful Incubation of Eggs of the Endemic Ryukyu Keelback, Amphiesma pryeri (Colubridae: Squamata)

Setsuko Iwanaga, Mamoru Toda, Hidetoshi Ota


A female of Amphiesma pryeri from Amamioshima, central Ryukyus, laid seven eggs. Five of these were dissected one week after being laid, of which four yielded embryos at stage 26 or 27 and the other appeared unfertilized. Remaining two eggs, incubated at constant 25°C, hatched after 58 – 59 days. The neonates averaged 210.5 + 76.5 mm in snout-vent + tail lengths and 5.1 g in weight.


Amphiesma pryeri; reproductive biology; embryonic stage; incubation period; hatchling size

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