Reproductive behaviour of the glass frog Hyalinobatrachium cappellei (Anura: Centrolenidae) in the Southern Amazon

Frog species of the Centrolenidae family exhibit a high variation in reproductive behaviours. Herein we describe the reproductive, ecological, acoustic and behavioural features of Hyalinobatrachium cappellei in Southern Amazon. Two hypotheses were also evaluated: (1) are ecological characteristics of the reproductive site related to male size and quantity of eggs and clutches? And (2) do males with one or more existing clutches at reproductive sites accumulate more new clutches than those males initially without them? This study was conducted at two streams, with sampling at 1 km each in Southern Amazon. Species reproduction occurred during the wet season and was considered prolonged breeding. Although male vocalization occurred on both the upper and underside of leaves, clutches were most often deposited on the underside of leaves. Males emitted a courtship call upon female approach. The process of female approach until oviposition lasted approximately eight hours. After oviposition, females left the breeding site while males remained near the clutch, covering it with the belly in ventral brooding behaviour. Thus, egg attendance is reported for the first time for this species. No intraspecific or interspecific aggressive behaviour was recorded. There was no relationship between habitat characteristics of the reproductive sites and male size, number of eggs and clutches. However, after 10 days of monitoring, we found evidences that parental males had a higher number of clutches than those males initially without clutches. Similar to other glass frog species, the behavioural characteristics of H. cappellei make this species an excellent model to use in evaluating the cost-effectiveness of parental care and the importance of egg attendance for offspring survival. Therefore, these data contribute towards a better understanding of the complex phylogenetic and biogeographic relationships between centrolenid lineages.

瞻星蛙科（Centrolenidae）的蛙类在繁殖行为上展现出极高的多样性。本研究对亚马孙南部的卡氏透体蛙（Hyalinobatrachium cappellei）的繁殖、生态、声学及行为特征展开描述，并验证两项假说：（1）繁殖位点的生态特征是否与雄性体型、卵粒数量及卵团数量相关？（2）繁殖位点上已拥有1个或多个卵团的雄性，是否会比初始无卵团的雄性积累更多新卵团？本研究在亚马孙南部的两条溪流开展，每条溪流均设置1千米长的采样断面。该物种的繁殖活动发生于湿季，属于持续型繁殖模式。尽管雄性的鸣唱行为可发生于叶片的正反面，但卵团大多被产在叶片下表面。雄性会在雌性接近时发出求偶鸣唱，从雌性接近到完成产卵的过程耗时约8小时。产卵结束后，雌性会离开繁殖位点，而雄性则会留在卵团附近，以腹部覆盖卵团，展现出腹面护卵行为。因此，本研究首次报道了该物种的护卵行为。研究未记录到种内或种间的攻击行为。繁殖位点的生境特征与雄性体型、卵粒数量及卵团数量之间未发现显著关联。但经过10天的监测后，我们发现携带卵团的护卵雄性，其新增卵团的数量显著高于初始无卵团的雄性。与其他玻璃蛙类群类似，卡氏透体蛙的行为特征使其成为评估亲代抚育成本效益，以及护卵行为对后代存活重要性的理想实验模型。因此，本研究数据有助于进一步阐明瞻星蛙科类群间复杂的系统发育与生物地理关系。