240 Acarology 



Type. Parerythraeus gregoryi Southcott, 1946 

 18. Sphaerolophiis Berlese, 1910 



a. Sphaerolophiis s. str. 



Type. Rhyncholophiis globiger Berlese, 1885 



b. Cavannea Berlese, 1910 



Type. Rhyncholophus cavannae Berlese, 1885 



c. Eupodolophiis Berlese, 1914 (= Fessoniella Hirst, 1924) 

 Type. Sphaerolophiis {Eupodolophiis) chiibbi Berlese, 1914 



Grandjean 1947 has separated the Erythraeidae into two families — 

 Erythraeidae and Balaustiidae — but this arrangement is not followed 

 here. 



Discussion: The larvae of these mites are parasitic on insects much 

 as the larvae of the Trombiculidae are parasitic on vertebrates. In one 

 case Lawrence 1940 found as high as 400 larvae of Erythraeus swa~ 

 zianiis Lawrence on a locust. Usually the number infesting an arthro- 

 pod is much smaller. Lawrence states that the "larvae seem to attach 

 themselves by the mouth-parts at all stages" and some of the molted 

 skins can be found still adhering to the host. Most of the larvae are 

 attached to the undersurface of the wings, and even to the tympanic 

 membrane within the organ and under the rim of the opening. They 

 are rarely found on the legs. Leptus atticolus Lawrence was taken 

 from the legs of a spider, Saitis sp., Attidae, in Natal, South Africa. 

 A mite identified as a Leptus sp. has been reared from lizards in Bou- 

 gainville in the South Pacific. This is the first record of an erythraeid 

 being parasitic on a vertebrate. Most species are known either from 

 the larva or the adult, very few having the different stages correlated. 

 Adults are free-living predators and may be found on foliage, in 

 humus or among leaves, and on the shore and sands. Balaustium 

 aonidaphagus (Ebeling) is reported as a predator of the red scale on 

 citrus in California. Ebeling 1934 states, "these mites are not ordi- 

 narily abundant and the writer has found them only in certain groves. 

 As high as thirty mites were found on a single tree, but ordinarily only 

 one or two, if any, are found. They may also be seen running about, 

 on the ground beneath the trees, which may, in part, be due to the 

 difficulty they experience in clinging to the foliage." They are cannibal- 

 istic and if a number are left together in a sealed container invariably 

 only one live mite will remain after a day or two. "The writer once 

 observed a mite thrusting its mandibles and finally its entire cephalo- 

 thorax beneath the armor of a red scale and feeding on the body ol 



