Records and descriptions of caddisflies from Natma Taung National Park and adjacent localities in the Chin Hills of Myanmar (Insecta, Trichoptera)

During several excursions to the Chin Hills of Myanmar from 2001 to 2015, rich collections of caddisflies were made which form the basis of the present taxonomic and biogeographic study. A total of 106 species were identified including seven new species. They are described as Arctopsyche subflava sp. nov., Hydromanicus abdominalis sp. nov., Cheumatopsyche janosolahi sp. nov., Lepidostoma subpanaitos sp. nov., Aplatyphylax pumilus sp. nov., Adicella natmataungensis sp. nov. and Triaenodes mindatensis sp. nov. Illustrations of the male genitalia and images of the adults are provided. Two species names were recognised as junior synonyms: Hydropsyche athamas Malicky & Chantaramongkol, 2000, = Hydropsyche januha Olah & Barnard, 2008, syn. nov.; Hydropsyche khasigiri Olah & Barnard, 2008, = Hydropsyche kiogupa Olah & Schefter, 2008, syn. nov. In an attempt to determine the biogeographic character of the fauna, the known ranges of all resident species were plotted into three longitudinal transects from 85°–95°E, 95–98°E and 98°–108°E, ranging from the eastern Himalayas to northern Vietnam. About half of the species have ranges extending over all three transects. The fauna is equally composed of western and eastern species qualifying the Chin Hills as part of a transition zone including palearctic elements. Most of the species, which are widely distributed in south-east Asia, are members of the suborder Annulipalpia. The investigations of the authors yielded 77 autochthonous species, which have been unrecorded from the country including the newly-described taxa. This brings the number of species records from Mynamar to 304.