Nine new species of Trigonopterus Fauvel (Coleoptera, Curculionidae) from Sundaland

The DNA of Trigonopterus specimens from the Sundaland region stored between ten and 32 years in museums could be used for next-generation sequencing. The availability of their cox1 sequence allowed the description of the following nine new species: Trigonopterusgrimmi sp. nov., T.johorensis sp. nov., T.lambirensis sp. nov., T.linauensis sp. nov., T.microreticulatus Riedel, Trnka & Wahab sp. nov., T.mulensis sp. nov., T.sarawakensis sp. nov., T.siamensis sp. nov., and T.singaporensis sp. nov. The alternative original spelling of the name T.tounensis Narakusumo & Riedel is chosen to prevail over T.tounaensis Narakusumo & Riedel. The new species represent the first country records of Trigonopterus for Brunei, Singapore, and Thailand. Thus, the genus´ known area of distribution in the Sundaland region is significantly extended. A key and a catalogue are provided to the Trigonopterus species from Borneo, W-Malaysia, Singapore, and Thailand.