The Rediscovery of a Relict Unlocks the First Global Phylogeny of Whip Spiders (Amblypygi).

This article focuses on the rediscovery and molecular phylogenetic analysis of a phylogenetic relict within Amblypygi (whip spiders), specifically the family Paracharontidae, previously known only from a single species, *Paracharon caecus*, last collected in 1899. The authors report a newly discovered species of *Paracharon* from Colombia, enabling the first global molecular phylogeny of Amblypygi using ultraconserved element sequencing combined with legacy Sanger data. Their analyses confirm Paracharontidae as the sister group to all other extant whip spiders (Euamblypygi) and reveal that excluding this relict lineage significantly biases divergence time estimates, more so than omitting ingroup fossil calibrations. The study also revises familial classifications by synonymizing Charinidae under Charontidae and highlights the importance of sampling phylogenetic relicts for accurate evolutionary, molecular dating, and biogeographic inferences, emphasizing the need for continued biodiversity discovery in tropical and subtropical habitats.