Distribution of Ecnomus McLachlan, 1864 (Trichoptera, Ecnomidae) from the Lower Mekong River with a description of Ecnomusstungtrengensis new species

Trichoptera were surveyed from four different physiographic regions of the Lower Mekong River, including the Northern Highlands, the Khorat Plateau, the Tonle Sap Basin and the Mekong Delta in Myanmar, Laos, Thailand, Cambodia and Vietnam. Twenty-three species of the genus , including a new species, were identified and mapped. Malicky & Chantaramongkol, 1993 is a common species which is found from Tonle Sab Basin and Mekong Delta. Malicky & Chantaramongkol, 1997, Malicky & Chantaramongkol, 1993 and Malicky, 1993 are the common species in the area of the Northern Highlands and the Khorat Plateau. Malicky & Laudee 2010 is found in the Mekong Delta. Sun, 1997 is a new species record for Southeast Asia. In addition, sp. n. is described and illustrated. The male genitalia of sp. n. are clearly different from those of other species in the genus by the shape of superior appendages which are slender and bent downwards distally in lateral view.