First Indochinese records of the plant bug genus Hypseloecus Reuter (Hemiptera: Heteroptera: Miridae: Phylinae: Pilophorini), with descriptions of eight new species from Thailand.

The phyline plant bug genus Hypseloecus Reuter is reported from Thailand as well as the Indochina region for the first time, diagnosed, and discussed on its phylogenetic position. Eight new species, Hypseloecus castaneus, H. katrinae, H. nigrobrevis, H. phuvasae, H. sakaerat, H. schuhianus, H. sericosagus and H. siamensis, are described, all with color photographic images of live individuals. Four species were confirmed to be associated with inflorescence and/or fruits of Loranthaceae mistletoe (Santalales), particularly Scurrula spp. in Thailand. A checklist of Asian and New Guinean congeners and a key to Asian species (from Japan, Indochina and Philippines) are provided.