28 MORPHOLOGY AND TAXONOMY OF ADULT MALES 



(ii) Scutellar setae (scls) . One or two hair-like setae are sometimes present on the 

 scutellum, but their occurrence is very irregular and variable even within a species. 



(iii) The tegular setae (tegs) are carried on the anterior part of the tegular bulge and 

 consist usually of a small number (up to n) of hair-like setae. Fleshy tegular setae 

 were only observed in Ceroplastodes chiton Green and occasionally in /. theobromae. 



(iv) The postmesospiracular setae (pms) are arranged in a broad band on the 

 membane posterior to the prosternum and mesothoracic spiracles. When they are 

 numerous, some setae may also occur on the episterna. They consist almost entirely 

 of fleshy setae and are only present in the COCCUS and INGLISIA groups. Their 

 numbers vary from 14-29 (average 21) in Ceroplastes to 71-97 (average 89) in P. corni. 



(v) The basisternal setae (stn 2 s) are situated on or near the median ridge in the 

 posterior part of the basisternum. They were found in only 3 species, consisting of 

 1 or 2 hair-like setae in N. abietis and P. piceae (Text-figs. 4, 6) and 2-9 (average 5) 

 fleshy setae in Genus B (Text -fig. 33). 



Metathorax 



The metathorax is very weakly sclerotized and the sclerites have to a large extent 

 been replaced by membrane ; this is due to the reduction of the hind wings. The 

 metanotum, however, is relatively well developed. It consists of a large plate which 

 closely overlaps the invaginated mesopostnotum. The dorsal edge (morphologically 

 posterior margin) of the sclerite is heavily sclerotized, forming a ridge-like structure 

 which usually extends continuously from one side to the other, but in a number of 

 species (e.g. E. tiliae, F. viburni, Ceroplastes spp.) its median part is somewhat 

 desclerotized. Externally the metanotum is represented by a small, lateral suspen- 

 sorial sclerite, which is connected to the haltere by means of a sclerotized band. 

 The suspensorial sclerites are absent when the halteres are lacking. Somewhat more 

 posteriorly an additional, small, weak sclerite is sometimes present (e.g. in E. tiliae, 

 L. luzulae, P. corni, Text-figs. 2, 27, 38), but it may be absent or present within the 

 same species. In the intersegmental region between the metathorax and 1st ab- 

 dominal segment there is an irregular, transverse, lateral sclerite which corresponds 

 to the acrotergite or postnotum (pn 3 ) of the more primitive Coccoidea (see Theron, 

 1958). In one of the species (L. luzulae, Text-fig. 27) the sclerites of the opposite 

 sides meet or closely approximate each other, and in another species (/. theobromae, 

 Text-fig. 29) they are divided by the intersegmental line. 



The degree of development of the pleural region depends to a considerable extent 

 on the absence or presence of halteres. The pleural ridge (plr 3 ) extends from the 

 coxal articulation in an anterodorsal direction across the pleuron. When the haltere 

 is absent (e.g. ERIOPELTIS, INGLISIA and COCCUS groups) the ridge only 

 extends for a short distance above the coxal articulation. When the haltere is 

 present, however, (most of the EULECANIUM group), it extends towards the base 

 of the haltere where it is slightly expanded to form a small metapleural wing process 

 (pwp 3 ). In this condition the ridge becomes weaker or is interrupted at about half- 

 way from the coxal articulation ; a shallow depression in this area appears to 

 represent a reduced metapleural apophysis (pla 3 ). 



