Unusual Genetic Diversity Within (Wood, 1862) (Chilopoda: Scutigeromorpha) Revealed by Phylogeny and Divergence Times Using Mitochondrial Genomes.

As one of the four primary evolutionary groups within myriapods, centipedes (Chilopoda) comprise approximately 3150 valid species. Recent molecular studies have begun to elucidate the phylogeny and time to divergence in Chilopoda; yet, identifying scutigeromorphs at the species level remains a notoriously challenging task. In this study, we obtained seven new complete mitogenomes of (Wood, 1862) to investigate the phylogeny and divergence times of Chilopoda. Both maximum likelihood (ML) and Bayesian inference (BI) analyses recovered the relationship of (Scutigeromorpha + (Scolopendromorpha + (Lithobiomorpha + Geophilomorpha))). For Scutigeromorpha, seven newly sequenced mitogenomes of were divided into four distinct clades. Divergence time estimates suggest that the basal split of Chilopoda occurred during the Middle Ordovician period, with the origins of Scolopendromorpha, Lithobiomorpha, and Geophilomorpha dating to the Devonian period. Factors such as warm climates, coevolution between predator and prey, and the rifting of the Hainan Island may have driven the diversification of Scutigeromorpha. Based on genetic distance, the delimitation of molecular species, phylogenetic relationships, and divergence time analyses, we identified three cryptic species that existed within . This exceptionally high degree of hidden diversity can be ascribed to the morphological stasis that has occurred since the Paleozoic era and taxonomic impediment.