Popis: |
Synchronous flashing fireflies of the genusPteroptyxare ubiquitous throughout Southeast Asia, yet, knowledge on its biodiversity and evolutionary history remains lacking. Recent studies have revealed notable population-level phylogeographic structure within theP. tenerandP. bearnigroups in Malaysia, suggesting that cryptic species may exist. Additionally, the close morphological and genetic affinity of the recently described speciesP. balingianatoP. malaccaehas raised questions about its validity. In this study, we assembled the most densely sampled genetic dataset onPteroptyxto-date to estimate a comprehensive phylogeny using mitochondrial and nuclear DNA and subsequently implemented a suite of distance-, phylogeny-, and coalescent-based species delimitation methods to characterize species boundaries within theP. tener,P. bearni, andP. balingiana/P. malaccaegroups. Using a total evidence approach from multiple lines of evidence, we showed that populations ofP. teneralong the west coast of Peninsular Malaysia are sufficiently divergent from populations from the east coast and Borneo to warrant specific recognition, despite the absence of morphological differentiation. Conversely, divergence ofP. bearnifrom Borneo and eastern Peninsular Malaysia, as well asP. balingianafromP. malaccaewere modest and their distinction as separate species were ambiguous; consistent with incipient species in the gray zone of speciation. Overall, this study contributes to the limited but growing body of genetic work on Southeast Asian fireflies and underscores the urgent need to increase the breadth and depth of geographic, taxonomic, and genetic sampling to provide a deeper understanding of their biodiversity and evolutionary history. |