Overview

The Haller's organ is found on the dorsal surface of the tarsi of leg I. It consists of the posterior capsule and the anterior pit.

The major function of this complex organ is believed to be olfaction.

6 or 7 sensilla have been found in examined ixodid ticks. These include multiporous, grooved, fine and non-pore 4 sensilla.
In argasid ticks, 9-11 sensilla occur in this region. Wall pore sensilla (=olfactosensilla), tip pore sensilla (=gustatory sensilla), tip pore seta (=multifunctional sensilla with gustatory, thermosensory and mechanosensory functions), non-pore sensilla (=thermosensilla and mechanosensilla) and several strictly mechanosensilla are known already.