MORPHOLOGY AND TAXONOMY OF ADULT MALES 



ones distinctly larger than the f.s. ; with 2 sensilla basiconica ventrally, one near apex and the 

 other more proximal. 



Thorax 650-749 (average 703) u. long. 



Prothorax. Pronotal ridge strong, but medially interrupted by weak sclerotization. Lateral 

 pronotal sclerites small, without setae. Medial pronotal setae and pores absent. Post-tergites 

 medium-sized, not striated, with 4-1 3 (average 7 -8) fleshy post-tergital setae occurring on and behind 

 the sclerite on each side. Pleural structures typical of family. Sternum with strong transverse 

 ridge, irregular median ridge and a small triangular sclerite. Anteprosternal setae : 0-6 

 (average 2-9) f.s. on each side ; prostemal setae : 10-54 (average 37) f.s. and 0-2 (average 1) 

 h.s., scattered over the sternal area and spreading into the area anterior to the spiracles. 



Mesothorax. Mesoprephragma with shallow emargination. Prescutum about if times as 

 wide as long (average 208 and 119 jx respectively) ; anterior margin strongly curved ; laterally 

 bounded by the prescutal ridges and posteriorly by the prescutal suture ; slightly more 

 heavily sclerotized medially, reticulation weak or absent. Scutum. Median membranous 

 area subrectangular ; 118-125 (average 123) \x long and 1-52-1-67 (average 1-59) times as 

 wide (width 179-209, average 196 ;x) ; with 15-28 (average 20) h.s. but no f.s. Scutellum 

 65-68 (average 67) [x long and 179-209 (average 196) [x wide, the ratio being 1 : 3-0-3-4 (average 

 3-2) ; tubular, with small ventral foramen ; without setae. Postnotum with anterior margin 

 irregular, weakly sclerotized and either exposed or partly overlapped by metathoracic fold ; 

 postnotal apophysis and postalare well developed, the latter densely reticulated distally and 

 occasionally with a fleshy postalary seta. Mesopostphragma with deep emargination. Meso- 

 pleuron. Mesopleural ridge strong, not interrupted above coxal articulation ; pleural apophysis 

 and pleural wing process well developed. Basalare vestigial, incorporated into pleural wing 

 process, not joining the latter with episternum. Subalare small. Episternum without poly- 

 gonal reticulation ; subepisternal ridge becoming broader ventrally, but below membranous 

 cleft indistinct and only marked by a band of darker sclerotization. Epimeron small. Latero- 

 pleurite not bounded by an extension from marginal ridge. Basisternum large, about 244 (x 

 wide and 212 jx long, i.e. 1 -67-1 -78 (average 1 -73) times longer than membranous area of scutum ; 

 with strong median ridge and bounded by strong marginal and precoxal ridges ; without setae. 

 Furca well developed. Mesothoracic spiracle with well developed peritreme ; postmesospiracular 

 setae numerous, consisting of 58-85 (average 74) f.s. arranged in a broad band behind the 

 spiracles and prosternum, with a few occurring on the episternae. Tegula small, membranous 

 bulge with a small weak sclerite posteriorly and with 4-8 (average 6) h.s. Third axillary wing 

 sclerite with a small, pointed, ventral projection at its base. Additional sclerite small, well 

 sclerotized. Antemetaspiracular setae : 3-7 (average 4-8) f.s. 



Metathorax. Metanotum with thickening of posterior margin usually desclerotized medially ; 

 suspensorial sclerites absent. Postnotum consisting of a small subtriangular sclerite on each 

 side. Metatergal setae : one h.s. and usually one (0-2, average 0-9) f.s. on each side. Pleural 

 ridge considerably reduced, extending only a short distance above coxal articulation. Epi- 

 sternum reduced to a small subtriangular plate ; epimeron produced posteriorly. Metathoracic 

 spiracle similar to mesothoracic one. Dorsospiracular setae : 10-19 (average 15) f.s. Post- 

 metaspiracular setae : 19-32 (average 25) f.s. and 0-2 (average 1) h.s. Metasternal plate weak 



\ N . 



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Fig. 36. Pulvinaria Pbetulae (L.), lateral view; also referable for lateral view of P. acericola 



(Walsh & Riley). 



