AN ASSOCIATION OF PHANERES, PROBABLY CONS TITUTING A NOVEL SYSTEM OF ACOUSTIC COMMUNICATION IN MITES

Grandjeanicus gabonensis Coineau & Theron n. sp. shows a functional gr ouping of two setae and a trichobothrium at the extremity of its first pair of legs, which is interpreted as novel system of acoustic commun ication. A hair termed C, which has its base solidly implanted on the tibia, is prolonged by a long, densely-ciliated flagellum, suspended o n a spring-like structure. A small posterior projection (lp) establish es contact with the trichobothrium (T) implanted on the tarsus which s lides in the middle of the supporting spring of the flagellum. Through its large surface of contact, the-latter can resonate in response to a relatively weak stimulus and transmit its vibrations to the trichobo thrium. The last segment of leg I also shows a solidly-implanted hyper trophied hair (A), the upper ridge of which bears a row of teeth, Flex ion of the tarso-apotele, relative to the tibia, places a spine (e) of hair C in contact with the row of teeth on hair A, thus causing micro stridulation. The system caused to vibrate in this way can in turn sti mulate the equivalent system borne by a conspecific.