Orthetrum internum was described by McLachlan in 1894. In Vietnam is was found by Do Manh Cuong in Vinh Phuc Province, at Tam Dao, but between 14 and 16 April we found this early flying species in Lai Chau, Lao Cai and Yen Bai Provinces as a common species. Likely it is widespread in Northern Vietnam, maybe overlooked because it flies so early. It differs from closely related O. japonicum for instance by the lack of pruinosity on the dorsum of the thorax. Here are a few photos from Phan Xi Pang and surroundings.
|The female Orthetrum internum hovering at ovipositing place over very shallow puddles|
|A male O. internum|
|The male hover-guarding the ovipositing female|