| abstract | Five species of the family Tetranychidae are reported for the first time in Sumatra, Indonesia. One of these species is described as new to science: Oligonychus sumatranus sp. nov. from Pithecellobium dulce (Roxb.) Benth. The new species is distinctive in that tibia I has eight tactile setae and the aedeagus gently bends ventrad to form a slender, nearly straight distal hook. The female of Schizotetranychus malayanus Ehara, 1988, previously unknown, is described; leg I of some females is recognized to exhibit the chaetotaxy similar to that in males. |