Neglected Trichalophus (Coleoptera: Curculionidae): DNA barcode and phylogeography of high-altitude flightless weevils rediscovered in Southwest China

摘要

Trichalophus LeConte weevils are rediscovered in Southwest China (Yunnan and Sichuan) after last being collected in 1915. Populations are all found at high altitudes (3704-4158 m) and are attributed to three species: T. caudic-ulatus (Fairmaire, 1886)(= compressicauda Fairmaire, 1887, syn. n.), T. scylla sp. n. and T. tibetanus (Suvorov, 1915). Type specimens of all four species-group names are illustrated. A DNA barcode library of five Trichalophus species (29 sequences) is presented at doi: dx.doi.org/10.5883/DS-TRICHAL. All examined species of Trichalophus are flightless. Phylogenetic relationships of Southwest China Trichalophus based on Maximum Likelihood and Maximum Parsimony analyses suggest their monophyletic origin and monophyly of each species. Results of the temporal analysis are consistent with the basic Quaternary expansion-contraction model of altitudinal range change. The warm period following the Last Glacial Maximum (26,000-19,000 years before present) is linked to the present dayhigh altitude Trichalophus refugium in Southwest China, but not for the lineage diversifications, which are much older (8.08-5.17 Mya). An illustrated overview of ten extant Alophini genera is provided.