Cnestus quadrispinosus, a new species of xyleborine ambrosia beetle from Thailand and Borneo (Coleoptera, Curculionidae, Scolytinae, Xyleborini)

A new species, Cnestus quadrispinosus, is described from Thailand, Brunei Darussalam, and East Malaysia (Sabah). It is compared to three related species of Cnestus which lack a mycangial tuft of hairs on the pronotum, and have an impressed elytral declivity.