T. transmarina euryale is widely distributed in south-east Asia, known for instance from Thailand, Cambodia and Hong Kong, even ranging to Japan, and its occurrence in Vietnam was to be expected.
|Tramea transmarina euryale, male|
|Tramea virginia, male|
|Hamule and genital lobe, T. transmarina euryale|
|And for comparison, hamule and genital lobe, T. virginia|