24 MORPHOLOGY AND TAXONOMY OF ADULT MALES 



is much reduced and only a pair of small, usually triangular plates represent the 

 sternites of segment VIII. 



The abdominal segment VI usually bears a pair of dorsal ostioles (ost) situated 

 sublaterally near the posterior margin of the segment ; these ostioles are sometimes 

 well developed, prominent and with a slit-like orifice (e.g. P. citri), or ill-defined 

 (e.g. P. obscurus), or absent altogether (e.g. N. nipae). According to Beardsley 

 (1964), two pairs of ostioles, though poorly defined, are present in the females and 

 the apterous males of Phenacoleachia australis ; apart from Pseudococcidae and 

 Phenacoleachiidae the ostioles are not recorded in the females or the males of any 

 other coccid family. 



The dermal structures of the pregenital segments : In Pseudococcus group, the 

 dorsal and the ventral setae (ads & avs) are arranged in transverse bands, composed 

 of both fleshy and hair-like setae ; in the remaining groups where only the hair-like 

 setae are present, they occur in segmental, transverse, irregular rows. The 

 abdominal pleural setae (aps) are arranged in lateral groups. 



A varying number of abdominal pleural pores (app) is usually present on segments 

 I to VII ; sometimes one or more segments of the abdomen are also with dorsal 

 pores (adp) (e.g. 0. africanus, Text-fig. 31), or ventral pores (avp) (e.g. S. sacchari, 

 Text-fig. 27), or both (e.g. D. alazon, Text-fig. 25). A cup-shaped glandular pouch 

 (gp) is present on each side of segment VIII near its posterior margin, formed by a 

 cluster of slightly smaller but numerous and tightly packed disc pores ; within the 

 pouch several setae (gls) originate, namely : 



(a) A pair of long and stout " tail setae " (ts), arising from the centre of the 

 pouch ; these setae are sometimes comparatively short (Nairobia group), or 

 moderately long (Ceroputo group), or long (the remaining groups). 



(b) There are also other shorter setae associated with the long ones : in Piano- 

 coccus, Pseudococcus and Saccharicoccus groups, a much shorter seta, but con- 

 spicuously longer than the body setae, is always present ; in Ceroputo and Nairobia 

 groups, this seta is subequal in length to the other abdominal setae ; in Octococcus 

 group, two setae of medium but subequal lengths, and a short one are present. 



In Ceroputo group, two pairs of glandular pouches and associated setae are 

 present, one each on segments VII and VIII. 



Genital segment and external genitalia 



The genital segment is ventrally modified to form a penial sheath (ps) (or " genital 

 valve ", Berlese, 1893), which represents the fused lateral parts of the 9th sternum 

 and distally terminates in a rather short projection, the style (st). A small sclero- 

 tized area occurs dorsally and probably represents the fused 9th tergite and the 

 10th segment (Theron, 1958), behind which a small anus (an) is situated just 

 anterior to the style. The style in lateral view, is slightly curved upwards (e.g. 

 P. citri), or straight with a pointed apex (N. bifrons), or straight with a rounded 

 apex (e.g. P. citriculus). Anteriorly, the ventro-lateral margin of the penial sheath 

 is heavily sclerotized, forming a basal ridge (brps). The latter is usually interrupted 



