The oak platypodid beetle, Platypus quercivorus, produced sounds by stridulating their abdomen against the elytra. When a female was put onto the bark surface of a male-infested log, she began to walk and produced an “approaching chirp”, searching for a gallery entrance bored by a male. When finding one, she entered it, and the male pushed her back. While they pushed against each other, the female made a “pre-mating buzz” that lasted about 5-10 s. During this buzzing, the male backed out of the gallery in order to allow her in. Females that had been silenced via surgery did not evoke this male reaction; thus, males apparently identified females by their buzzing sound. The male then followed the female into the gallery, and produced an “in-gallery chirp” with his posterior abdomen visible. After a while, both sexes backed out of the hole and copulated at the entrance. Both sexes produced “stress chirps” when confined inside a cotton ball, and “spontaneous chirps” when walking alone on the surface of an oak bark piece. There are two local types in Japan and the inter-pulse-intervals in their buzzes were different.