Crista acustica


Crista acustica is a part of the hearing organ in some insects. It is a collection of sensory cells that form a crest on top of the hollow tube behind the hearing membrane on the legs of the insect.
The crista acustica is a transition from the intermedia organ, together which compose the tibial hearing organ.
The crista acustica is one of three fiddle-string-like organs or chordotonal organ in insects: the others are the intermediate organ and the supratympanal organ/subgenual organ. These chordotonal organs are actually collections of sensory cells sensitive to vibration. Their cells are attached to the tube in the legs of the insects. So when the tube vibrates, the cells vibrate. In the crista acustica, it turns out that different scolopidia cells are sensitive to different vibrations depending on the frequency of the vibration. Since these organs are sensitive to vibrations , and the cells further out are smaller and sensitive to higher frequencies. This orderly arrangement of sensory cells gives the insect the ability to discriminate frequencies, much like the inner ear of mammals.