A New Aphis on California Sage 



APHIS HILTONI n. sp. 



(Figure 1) 



By E. 0. Essig, Division of Entomology 

 University of California 



Apterous Viviparous Female. — 



(Figure 1, A). Length 1.3 mm., width of abdomen 0.9 mm. 

 Prevailing color pale green, the dorsum partially covered with a 

 fine white powdery wax which is arranged in minute pore-like or 

 mosaic rings. The areas not so covered appear dark in the illus- 

 tration. There are numerous black pigmentations dorsally and lat- 

 erally on the epidermis of the mounted specimens. The cornicles, 

 Cauda and anal plate ; all of the legs excepting the basal three- 

 fourths of the tibiae ; and antennal articles, VI, V, II, I and the tip 

 of IV are black or dusky. The remainder of the antennae and tibiae 

 are yellow. The rostrum extends slightly beyond the base of the 

 abdomen. The antennae are shorter than the body, the relative 

 lengths of the articles being : 



I. 0.065 mm., II. 0.055 mm.. III. 0.227 mm., IV. 0.167 

 mm., V. 0.155 mm., VI. 0.280 mm., (base 0.130 mm., spur 0.150 

 mm.), total length 0.949 mm. There are the usual sensoria on 

 articles V. and VI. The prothoracic tubercle is well pronounced. 

 There is also a well defined pair of antei'ior and a pair of posterior 

 abdominal tubercles (Figure 1, A. tub. i, ii, iii). The tarsi are 

 small and one-third as long as the cornicles. (Figure 1, At.). 

 The cornicles are black, cylindrical and somewhat tapered towards 

 the tip, straight, slightly imbricated; 0.37 mm. long, and 0.06 mm. 

 wide at the base. The cauda and anal plate are black (Figure 1, 

 A. Cauda). 



Winged Viviparous Female. — 



Length 1.20 mm., width of abdomen 0.56 mm. Prevailing 

 color black with abdomen and legs dusky yellow. The dorsum may 

 also be partially covered with a fine white powdery wax. The 

 antennae (Figure l.W. ant) are dusky to black throughout, the 

 length of the different articles : I. 0.070 mm., II. 0.050 mm.. III. 

 0.200 mm., IV. 0.155 mm., V. 0.153 mm., VI. 0.280 mm. (base 0.125 

 mm., spur 0.155 mm.), total length 0.908 mm. Article III usually 

 has four or five large circular sensoria along the lower side, but 

 there are sometimes six. The usual sensoria occur on V and VI. 

 The rostrum reaches to the second abdominal segment. The pro- 

 thoracic and abdominal tubercles are much like those in the apter- 

 ous form and are illustrated in Figure 1, W. tub. The wings (Fig- 

 ure 1, W.) are normal in venation as illustrated. The lengths are: 



