The unexpected genetic mating system of the red‐backed toadlet (Pseudophryne coriacea): a species with prolonged terrestrial breeding and cryptic reproductive behaviour

Molecular technologies have revolutionised our classification of animal-mating systems, yet we still know very little about the genetic-mating systems of many vertebrate groups. It is widely believed that anuran amphibians have the highest reproductive diversity of all vertebrates, yet genetic mating systems have been studied in less than one percent of all described species. Here, we use SNPs to quantify the genetic-mating system of the terrestrial breeding red-backed toadlet Pseudophryne coriacea. In this species, breeding is prolonged (approximately 5 months), and males construct subterranean nests in which females deposit eggs. We predicted that females would display extreme sequential polyandry because this mating system has been reported in a closely-related species (P. bibronii). Parentage analysis revealed that mating success was heavily skewed towards a subset of males (30.6% of potential sires), and that nearly all females (92.6%) mated with one male. In a high percentage of o...分子技术彻底革新了动物交配系统的分类范式，但时至今日，我们对诸多脊椎动物类群的遗传交配系统仍知之甚少。学界普遍认为，无尾两栖类（Anuran amphibians）拥有所有脊椎动物中最高的繁殖多样性，但迄今已开展遗传交配系统研究的物种尚不足所有已描述物种的1%。本研究借助单核苷酸多态性（Single Nucleotide Polymorphism, SNPs）标记，对陆生性繁殖的红背小蟾（Pseudophryne coriacea）的遗传交配系统进行定量解析。该物种繁殖周期较长（约5个月），雄性会构筑地下巢穴以供雌性产卵。我们曾预测雌性会表现出极端连续多配制，因为其近缘物种（P. bibronii）中已有该类交配系统的报道。亲权分析结果显示，交配成功率高度偏向于少数雄性（仅30.6%的潜在父本成功获得交配机会），且近92.6%的雌性仅与1只雄性完成交配。在高比例的卵……