Argasidae

The Argasidae are a family of ticks containing the soft ticks. They lack the hard scutum present in the hard ticks (Ixodidae). The capitulum (mouthparts-bearing structure) is located on the underside of the animal's body and is not readily visible. The family contains 193 species, although the composition of the genera is less certain, and more study is needed before the genera can become stable. The currently accepted genera are Antricola, Argas, Nothoaspis, Ornithodoros, and Otobius.