Abstract
A new species Nihonogomphus schorri Do & Karube, sp. nov. is described on the basis of male specimens collected from Huu Lien Nature Reserve, Lang Son Province, northern Vietnam. It is close to the Chinese species N bequaerti Chao, 1954 due to the similarity of hamules, anal appendages and vesicle, but is easy to-separate from that species by the vesica spermalis structure and body markings. During a field trip to Huu Lien Nature Reserve in Lang Son Province together with Matti Hamalainen in June 2008, a male specimen of a Nihonogomphus was collected. The first author observed also a female of the same species and managed to get some photographs, but unfortunately the dragonfly flew away before it could be collected. In May 2009, Hamalainen returnedto Huu Lien and he collected another male specimen on the same stream. This specimen was sent to the second author. Detailed study of these specimens has convinced the authors that it is a new Nihonogomphus species, which is described here.
NSTL