24 MORPHOLOGY AND TAXONOMY OF ADULT MALES 



The scutum (set) has a rather curious shape. The median membranous area, 

 which is comparatively small in the margaroid Pseudaspidoproctus and Steingelia 

 (Theron, 1958), has in this family become so expanded that it completely and widely 

 separates the two lateral sclerotized parts. These extend anteriorly along the 

 sides of the prescutum and posteriorly along the sides of the scutellum. In the 

 anterolateral region the scutum is produced into a prealare (pra), which is separated 

 from the former by an internal lamina. The prealare is semitubular in shape, with 

 the more heavily sclerotized and infolded anterior margin continuous with the 

 mesoprephragma. The distal part of the prealare is differentiated into a heavily 

 sclerotized, convex triangular plate (tp), which extends to the episternum. Behind 

 the prealare the lateral margin of the scutum is infolded and somewhat more heavily 

 sclerotized, the infolded section of the margin terminating in a small rounded 

 projection which constitutes the anterior notal wing process (anp). From this level 

 the posterior extension of the scutum is depressed, laterally emarginated and with a 

 rounded posterior lobe which can be regarded as the posterior notal wing process 

 (pnp). The posterior margin of the scutum probably incorporates the lateral part 

 of the so-called marginal fold of the notum ; posterolateral^ it is attached to the 

 postalare by means of a sclerotized band. Part of the scutum adjacent to the 

 scutellum is more heavily sclerotized and usually reticulated. This probably led 

 Theron (1958) to misinterpret it as part of the scutellum, as indicated in his illus- 

 tration of P. pomeranicum. The anterior part of the scutum may also show reticula- 

 tion (e.g. Ceroplastes spp., Text-figs. 41, 43) and even the median membranous area 

 may be weakly reticulated (Eriopeltis sp., L. luzulae ; Text-figs. 24, 27). 



The scutellum (scl) in dorsal view has the shape of a transverse rectangle. The 

 anterior and posterior edges, constituting the scutoscutellar ridge and the posterior 

 marginal fold of the notum respectively, curve sharply inwards, are deflected under 

 the scutellum and extended internally. The inner edges usually have become 

 intimately fused, leaving only an oval median foramen (self) (F. viburni, Ctenochiton 

 sp., S. prunastri, ERIOPELTIS group, COCCUS group). This gives the scutellum 

 the appearance of a dorsoventrally flattened tube. In some species, however, the 

 inner edges do not unite with each other (/. theobromae and most species of the 

 EULECANIUM group). In the species where the scutellum is tubular it is usually 

 shorter and wider than in those where the scutellum is not tubular. The scutellum 

 was called the " apodema " by Putnam (1879), Green (1904-1909) and Durr (1954) 

 while Habib (1956), Borchsenius (1957) and Bustshik & Saakjan-Baranova (1962) 

 regarded it as part of the scutum. The scutellar foramen was referred to as a 

 " membranous area " by Pesson (1941), Jancke (1955), Ezzat (1956) and Borchsenius 

 (1957). Bustshik & Saakjan-Baranova (1962) state that it is absent in C. hesperidum. 



The scutellum is followed by a large, subtriangular membranous area which 

 separates it from the postnotum. This membranous area was regarded as the 

 scutellum by Putnam (1879), Green (1904-1909), Habib (1956) and Borchsenius 

 (1957), and as the postnotum by Sulc (1932), Pesson (1941) and Jancke (1955). 

 The postnotum (pn 2 ) is a curved structure which extends deeply into the metathoracic 

 cavity and is overlapped by the similarly inflected metanotum. The anterior margin 



