Molecular Phylogeny And Biogeography Of The World Panorpidae(mecoptera)

Panorpidae is the most speciose family in the order Mecoptera and comprises approximately 400 described species. Panorpidae are currently assigned to six genera, Panorpa Linnaeus, 1758; Leptopanorpa MacLachlan, 1875; Neopanorpa Weele, 1909; Sinopanorpa Cai & Hua, 2008; Furcatopanorpa Ma & Hua, 2011, and Dicerapanorpa Zhong & Hua, 2013. Previous phylogenetic studies of Panorpidae are mainly based on morphological data, and the phylogenetic relationship within Panorpidae has not been adequately explored. The extant Panorpidae are widely distributed throughout Asia, North America and Europe, with only a few fossil records. Therefore, the divergence time, origin, and biogeography of Panorpidae have not been satisfactorily studied to date.Here we analyzed the phylogenetic relationships and estimated the divergence time among 70 species of five genera in Panorpidae using maximum likelihood and Bayesian inference based on two mitochondrial(cox1 and cox2) and one nuclear(28S rRNA) gene fragments with Panorpodes kuandianensis and Brachypanorpa carolinensis in Panorpodidae as outgroups.The results show that the genera Neopanorpa, Sinopanorpa and Dicerapanorpa are monophyletic, while the most speciose and widespread genus Panorpa is reconfirmed to be a paraphyletic group. The P. centralis group is monophyletic and may merit a generic status, while the P. davidi and P. amurensis groups are paraphyletic.The divergence time estimated from BEAST analysis indicates that the Panorpidae may originate in the period from middle Jurassic(173.9 mya) to early Eocene(52.5 mya), and most speciation and diversification within Panorpidae occurred in the Cenozoic. Panorpa originated in middle Eocene, slightly precede the origin of Neopanorpa(35.7 mya). Asia may be the center of origin of Panorpa because of the high species abundance and diversity. Asian species of Panorpa probably migrated into North American via the Bering land bridge, and dispersed to Europe after Turgai Strait dried up. The divergence time of Panorpa in Europe(33.7 mya) was earlier than North America(22.9 mya), and the North American species of Panorpa are more closely related to the Asian than European species.