CHAPTER XXVII 



TRIBE ASPIDIOTINI 



The Deltoid Scales 



The body of the adult female is broader than long, rarely slightly 

 longer than broad. The cephalic end is usually broadest, broadly 

 rounded, and the two lateral margins converge caudad to a bluntly 

 rounded point. The body has a distinct triangular or deltoid outline. 

 The indentations in the lateral margin of the thorax and preabdomen 

 marking the position of the coriae may be distinct, but are frequently 

 obscure. The segmentation of the preabdomen is always more distinct than 

 that of the other parts of the body. The lateral margins of the segments 

 of the preabdomen are never provided with bracteae in either the 

 adult or second nymphal female. Lobes are usually present in the 

 adult female, typically three pairs, although more or less than this 

 number may be present, or they may be absent, or absent and repre- 

 sented by pseudolobes. Pectinae and plates are usually present, 

 pectinae may be of any type, only rarely distapectinae. The incisurae 

 are usually narrow and filled with pectinae or plates, sometimes small. 

 Densariae and paraphyses are frequently present. Altaceratubae are 

 never present or at least very rarely. Brevaceratubae at most only 

 rarely present, are never arranged in crescentic transverse rows, and 

 are replaced by clavaceratubae and linaceratubae. Genacerores are 

 frequently present, arranged in five, four, or two groups. The meso- 

 genacerores, when present, usually consist of only a few pores, about 

 six or less, frequently wanting. Scale of the adult female coriaceous 

 or thin and usually brownish, reddish, blackish, or grayish in color, 

 rarely white. Typical in form, round with the exuviae at the center, 

 one exuvia superimposed over the middle of the other, scale rarely 

 oval in outline with the exuviae slightly eccentric, but never at or 

 projecting beyond the margin, never pyriform or mussel-shaped, rarely 

 two or three times as long as broad with subparallel sides. The 

 female sometimes transforms in a puparium so that the scale of the 

 adult female may contain only the first exuvia and the pygidium is 

 usually provided with pseudolobes. The scale of the male is similar 

 in shape and color to that of the female but differs in having a single 

 exuvia. It is never provided with a mesal carina and is rarely chalky 

 white in color. 



A considerable number of the injurious species of the Diaspi- 

 dinae belong to the tribe Aspidiotini. In fact not only some of 

 the most injurious but some of the best known species of coccids, 



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