Unique breeding activity and oviposition in Annandale's high-altitude tree frog, Kurixalus naso (Annandale, 1912) in Meghalaya, North East India

摘要

The present study highlights the unique characteristics of the breeding activity and oviposition of Annandale's high-altitude tree frog, Kurixalus naso (Annandale, 1912) at Mawsynram, Meghalaya, North East India. After the cold, dry, winter months (September-January), the first rainfall in February triggers the onset of a short breeding activity of the species, which lasts for 3-4 weeks during February to March. The first shower causes an increase in soil moisture content and decrease in soil temperature. Immediately after the first showers, males make their advertisement calls, followed by females engaging in amplexus with the males and ovipositing in the moist soil. The females come only once to the breeding site and leave after mating; parental care is provided by the males. Multiple amplecting pairs at the breeding site are seen inside the burrows and some are observed to amplect in the open soil surface, lasting for 5-6 h. No aggregation and competition among the males is observed. The amplecting females lay eggs inside the excavated burrows and the males, using their hind limbs, expose the eggs by pushing them to the mouth of the burrowing hole. Sometimes, the females oviposit at the base of hollow tree trunks and occasionally in the open soil surface. The eggs are mixed with the soil and they resemble perhaps masquerade as seeds. Most frogs display a biphasic life cycle. However, K. naso shows a distinct non-aquatic oviposition with aquatic larva. Further, soil moisture content and temperature may support the development of embryos in open soil surfaces and burrows.