THE SCALE INSECT GENUS ASTEROLECANIUM 3 



GEOGRAPHICAL DISTRIBUTION 



Representatives of the genus have been collected in each of the 

 6 major zoogeographical regions of the world, and from 22 of the 24 

 subregions, no species having been reported as yet from the Siberian 

 Subregion of the Palearctic Region, or the Celebesian Subregion of 

 the Oriental Region. 



HOST ASSOCIATIONS 



Although species of Aster 'olecanium have been found on at least 

 37 plant families ranging from the Gramineae to the Compositae, 

 they are most numerous on the Gramineae, Palmae, and Fagaceae. 

 The species occurring on bamboos, palms, and oaks are, so far as 

 known, limited to their respective host groups, but others may be 

 found on members of several plant families, and still others appear 

 to have a marked preference for a single host family and rarely occur 

 on other, unrelated, hosts. Some members of the genus seem to be 

 restricted in their feeding to one part of a plant, such as the leaves, 

 stems, or bark, while others live indiscriminately on leaves, stems, 

 twigs, fruit, and trunk. Some species apparently never produce 

 pits, while others cause pits in some plants but not in others; thus 

 the habit seems partially dependent upon the susceptibility of the 

 host to pit formation. 



RELATIONSHIPS 



Asterolecaniuni belongs in the family Asterolecaniidae, subfamily 

 Asterolecaniinae. The subfamily is poorly defined, and the total 

 number of genera correctly assignable to it is debatable. The sub- 

 family, as treated in this paper, is characterized in the adult females 

 by the presence of comparatively sessile 8-shaped pores and asym- 

 metrical tubular ducts and by the absence of characters which might 

 indicate a closer relationship with some other group. The following 

 genera (on the basis of their genotypes) are here included: Amelo- 

 coccus Marchal, Amorphococcus Green, Anomulococcus Green, Aster- 

 olecanium Targioni-Tozzetti, Birchippia Green, Callococcus Ferris, 

 Cerococcus Comstock, Frenchia Maskell, Lecaniodiaspis Targioni- 

 Tozzetti, Olliffia Fuller, Polea Green, and Solenococcus Cockerell. 



The family Asterolecaniidae is more closely related to the Coccidae 

 and Dactylopiidae than to other families. This .affinity is evinced 

 by the presence, in some representatives of Asterolecaniinae, of 

 loculate pores associated with the spiracles, by the presence of spi- 

 racular setae and modified anal plates, and by the outline of the 

 posterior margin of the body, which may be cleft or strongly 

 lobed. All these characters are found in the families Coccidae and 

 Dactylopiidae. 



Within the subfamily, Asterolecamiim is most closely related to 

 Amorphococcus, Frenchia, and Polea. Adult females of these genera 

 have a tubular duct which is thickened on one side near the inner end, 

 usually bends slightly entad of the thickening, and is of practically the 

 same diameter each side of the thickening. They do not have spiracu- 

 lar spines or cribriform plates, and the posterior margin of the body is 

 not cleft or strongly lobed. Larvae of these genera usually have i2S 

 marginal 8-shaped pores, a ventral submarginal row of minute 



