CHAPTER VII 

 SUBFAMILY XYL.OCOCCINAE 



The Melratiiban Coccids 



The body of the adult female is rotund or convex on the dorsal and 

 flat on the ventral aspect. It is elongate elliptical or rotund and glob- 

 ular, broadest in the thoracic region. The lateral margins are convex 

 and the caudal margin is subtransverse or uniformly convex. The 

 segments are well defined. The caudal end of the body is not inflated 

 and the cephalic and lateral margins are not provided with a keel. The 

 antennae are prominent, consisting of five to eleven segments and are 

 articulated to the ventral aspect of the head near each lateral margin. 

 The eyes are present. There is a single ocellana located on each side of 

 the head near the articulation of an antenna. The mouth-parts, rostrum 

 and rostralis, are always wanting. The legs are usually present. They 

 are subequal in length and normal in form. The profemora are never 

 enlarged and the prothoracic legs are never fitted for digging. The tro- 

 chanto-femoral and the tibio-tarsal sutures of all the legs are always 

 distinct. The spiracles of the mesothorax and metathorax are small and 

 inconspicuous and ventral in position or are large and conspicuous. 

 The mesothoracic spiracles are never located adjacent to the anus. The 

 abdominal spiracles are located on the lateral or ventral aspects, six or 

 eight pairs, and are large in size. The spiracular tracheae of the 

 abdominal spiracles are frequently provided with one or more rings of 

 cerores. The stigmatic clefts, spinae, and canellae are wanting. The 

 abdomen is about as long as the head and thorax together. It is convex 

 on the dorsal and ventral aspects, never depressed. The lateral margins 

 are convex and the caudal end is subtruncated or convex. All of the 

 segments are fully exposed and similar in appearance with distinct coriae 

 between them, none are retracted to form a marsupium. The abdomen 

 is never provided with an anal cleft and opercula, an anal ring and anal 

 ring setae, or anal lobes and anal setae. The caudal abdominal segment 

 is short and narrow, small and inconspicuous, and extends beyond the 

 other segments or is normal in form and not protruding. The segments 

 are not campanulate. The body is provided with cerores, none of which 

 are octacerores or pilacerores, and is never provided with ceratubae. The 

 body is never enclosed in a resinous cell with three adjacent openings or 

 covered by a scale with or without exuviae, but may be more or less 

 covered or associated with white, mealy, powdery, or filamentous wax. 

 The rectum is rarely if ever provided with a long glassy tube of wax 

 or with a chitinized rectal tube bearing rings of anacerores. The body 

 is never naked and gall-like in form. 



The female nymphs of all stages are provided with a rostrum of two 

 segments and a rostralis. The three pairs of legs are present in the first 



80 



