An integrative assessment of the taxonomic status of putative hybrid leopard frogs (Anura: Ranidae) from the Chortís Highlands of Central America, with description of a new species

Integrative taxonomy seeks to approach the complex topic of species diagnosis using independent, complementary lines of evidence. Despite their ubiquity throughout North and Central America, taxonomy of the American leopard frogs (Anura: Ranidae: <i>Rana</i>: subgenus <i>Pantherana</i>) remains largely unresolved, and this is arguably nowhere truer than in the Central American country of Honduras, where there are two nominal species, the taxonomy of which remains unresolved. Leopard frogs from several mountainous areas along the continental divide in Honduras have previously been considered putative hybrids between <i>Rana brownorum</i> and <i>R.</i> cf. <i>forreri</i>, as opposed to two alternate hypotheses: one that they represent a high-altitude eco-morph of a single widespread species that included both lowland forms, or a second that there is an undescribed highland species distinct from either of the recognized lowland forms. We examine this set of hypotheses using three independent lines of evidence. First, we used species distribution modelling to examine potential geographic isolation of the highland form and the two putative parental lowland species, and found strong ecological separation between the highland and lowland forms. Second, mitochondrial and nuclear DNA supports the distinction of the highland form from both putative parental species, with mtDNA data refuting the hypothesis that representatives of either species may represent a matrilineal founder. Morphologically, the highland form is significantly smaller than, and otherwise readily differentiated from, both <i>R. brownorum</i> and <i>R.</i> cf. <i>forreri</i>, as well as all other <i>Rana</i> found in Honduras and adjacent areas. As a result, we formally describe the highland leopard frog as a new species. http://zoobank.org/urn:lsid:zoobank.org:pub:BE53F587-3618-4433-9651-E495808E5474

整合分类学（Integrative taxonomy）旨在通过独立且互补的多重证据线索，探究物种鉴定这一复杂议题。尽管美洲豹蛙（无尾目（Anura）：蛙科（Ranidae）：林蛙属<i>Rana</i>：豹蛙亚属<i>Pantherana</i>）在北美与中美洲广泛分布，但其分类学研究仍未得到充分解决；这一问题在中美洲洪都拉斯尤为突出，当地存在两个定名物种，其分类学关系始终悬而未决。此前，洪都拉斯沿大陆分水岭若干山区的豹蛙种群被认为是<i>Rana brownorum</i>与<i>R.</i> cf. <i>forreri</i>之间的推定杂种。对此学界存在两种替代假说：其一，该种群是包含两种低地类群的单一广布物种的高海拔生态型；其二，存在一种未被描述的高地物种，区别于所有已确认的低地类群。本研究采用三类独立证据对上述假说进行验证：首先，通过物种分布模型分析高地类群与两种推定亲本低地物种的潜在地理隔离情况，结果显示高地类群与低地类群间存在显著生态分化；其次，线粒体与核DNA序列数据证实高地类群与两种推定亲本物种存在显著分化，其中线粒体DNA（mtDNA）数据驳斥了"该类群代表个体可能源自任一亲本物种的母系创始种群"的假说；形态学层面，高地类群体型显著小于<i>R. brownorum</i>与<i>R.</i> cf. <i>forreri</i>，且可与洪都拉斯及邻近区域分布的所有其他林蛙属物种轻易区分。基于上述结果，本研究正式将该高地豹蛙描述为新物种。http://zoobank.org/urn:lsid:zoobank.org:pub:BE53F587-3618-4433-9651-E495808E5474