A REVIEW OF THE VELIINAE OF VIETNAM (HETEROPTERA: VELIIDAE) WITH DESCRIPTION OF A NEW VELIA SPECIES

Abstract

The Veliinae of Vietnam are reviewed, and the new species Velia tonkina described from the Huong Lien Son mountains in the far north of the country. Three additional species of Veliinae, Chenevelia stridulans, Angilia bispinosa, and Angilia orientalis, are recorded from Vietnam for the first time. Distribution maps are provided for all these species, dorsal habitus illustrations are provided for Velia tonkina and Chenevelia stridulans, and illustrations of male genitalic structures are provided for Velia tonkina. In a recent paper (Polhemus and Polhemus, 1999) the authors described several new species of Veliinae from Nepal, Java and Burma, and noted that the southwestern margin of the Himalayan uplift as it descends into the hill country of Indochina is a rich zone of intermingling between veliid faunas characteristic of both temperate and tropical Asia. Recent collections in Vietnam have further emphasized this pattern, resulting in the collection of a new species, Velia tonkina, described herein. The discovery of V. tonkina extends the range of the predominantly temperate genus Velia to the eastern margin of the Eurasian continent via the ridge of the Houng Lien Son mountain range, a high, unbroken salient which projects eastward from the main Himalayan uplift in Yunnan. These mountains, lying along the southern border of the Red River Valley, represent a corridor of temperate habitat in an otherwise tropical region, and harbor many other species of aquatic Heteroptera found nowhere else in Vietnam. In addition to V. tonkina, the first Vietnamese collections for three other previously described species of Veliinae have also been obtained during our recent surveys, with a particular richness of species on wet eastern face of the Vietnamese Central Highlands, where the flanks of the Annamite mountain chain approach the South China Sea. In this paper these new discoveries are documented, and distribution maps provided for all of the species involved.