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The Negros Fruit Dove Ptilinopus arcanus is an enigmatic bird known only from a single specimen collected on Negros Island, Philippines, in 1953. We extracted and sequenced ultra‐conserved elements from historical toe‐pad samples of the type specimen of P. arcanus and 27 other species of ptilinopine doves to investigate the species status and phylogenetic relationships of this taxon. We establish that P. arcanus represents a valid species, resolve its phylogenetic position at the base of the radiation of 'core' Ptilinopus fruit doves, and estimate that P. arcanus diverged from its most recent common ancestor several million years before Negros Island emerged from the seafloor. We also perform an ancestral range reconstruction to evaluate the effect of different altitudinal preferences on the putative historical range of this species, and we discuss how these findings can inform future efforts to relocate and potentially conserve this species. [ABSTRACT FROM AUTHOR]

Aim: Biotic interchanges between Africa, India, and Eurasia are central to explaining the present‐day distribution and diversity of freshwater organisms across these landmasses. Synbranchiformes is a diverse and species‐rich clade of freshwater acanthomorph fishes found on all southern continents except Antarctica, and include eel‐ and perch‐like, air‐breathing and non‐air‐breathing fishes. Lacking a comprehensive and resolved phylogeny of the entire clade, contemporary interpretations of synbranchiform biogeography invoke scenarios as disparate as Gondwanan vicariance and pan‐global rafting to explain their modern‐day distribution. Here, we study their biogeographic history of continental dispersal events and test whether these are associated with increases in lineage diversification. Location: Asia, India, Africa freshwater habitats. Taxon: Synbranchiformes (gouramis, snakeheads, swamp eels, and relatives). Methods: We used nearly 1000 ultra‐conserved elements (UCEs) and Sanger‐sequenced genes to infer a phylogeny with representatives of all major synbranchiform lineages and nearly two‐thirds of its known species diversity. Incorporating fossil calibrations, we inferred a time‐calibrated phylogeny to which we apply Bayesian methods of ancestral area reconstruction and test for diversification rate shifts. Results: Analyses of UCE data provide a resolved phylogeny for major synbranchiform lineages. Divergence times support a most recent common ancestor of the entire clade approximately 79.2 million years ago. We infer significant increases in lineage diversification in both the spiny eels (Mastacembelidae) and the genus Betta (Osphronemidae). Main Conclusions: Our results reject the hypothesis of Gondwanan vicariance explaining synbranchiform biogeography. Instead, our analyses reconstruct a southeast Asian origin of the entire clade and independent dispersal events to other continents by snakeheads, anabantids, and spiny eels, with no signal of elevated lineage diversification occurring after these invasions. Higher lineage diversification rates in spiny eels pre‐date their arrival to Africa, while the high diversification rates observed in Betta were initiated prior to the flooding of insular Sundaland in southeast Asia. [ABSTRACT FROM AUTHOR]