Abstract: | The Australian species of Chromotydaeus Berlese and Penthaleus C. L. Koch (Acarina: Penthaleidae) are revised. Chromotydaeus quartus n. sp. and Penthaleus falcatus n. sp. are described, and P. major (Dugés) and P. minor (Canestrini) redescribed. P. major is an agricultural pest, but all the other species appear to have no economic importance. |