HOST RELATIONS AND DISTRIBUTION OF THE AUSTRALIAN SPECIES OF EUTROMBIDIUM (ACARINA, MICROTROMBIDIIDAE), A PARASITE OF GRASSHOPPERS

The geographical distribution of parasitism of Australian grasshoppers by the microtrombidiid mite Eutrombidium australiense is delineated. It appears to extend over almost the whole of mainland Australia. At l east 248 species are attacked, in the subfamilies Morabinae, Pyrgomorp hinae, Oxyinae, Catantopinae (including Cyrtacanthacridini), and Acrid inae. The dominant sites of attachment are the insertion of leg III an d the prosternum, between them accounting for 80% of cases, with the f irst the more frequent. Most of the host individuals were attacked by only one mite, but more than 20 were occasionally recorded.