APHIDIDAE OF SOUTHERN CALIFORNIA V 



BY E. O. ESSIG 

 HORTICULTURAL COMMISSIONER OF VENTURA COINTV, CALIFORNIA. 



Aphis hederae Kaltenbach 



U'iiii^cd I k'iparous female (Fig. 124 A). — Average length, 1..^ iidh., 

 average width 5 mm., wing expansion 4.5 mm. Prevailing color — Shiny black 

 throughout. In mounted specimens the color may become dark brown, due 

 to the action of the mounting materials. Head — Narrower than thorax, and 

 nearly as long as wide. Compound eyes — coarsely faceted, jet black, with 

 usual terete tubercles on outer margins. Antennae (Fig. 124 A) arise from 

 slight frontal tubercles, which are not prominent, three-fourths the lengtii 

 of the body, 6 (commonly called 7) -articled. The first two articles are very 

 dark, while the remainder are from a dark yellow to an amljer color. The 

 antennae vary considerable, because of the variability of the insect. The 

 following lengths are approximate: I 0.05 mm., II 0.05 mm.. Ill 0.22 mm.. 

 IV 0.19 mm., \' 0.17 mm., VI 0.37 mm. Sensoria are quite numerous on 



Figure 124. Aphis hederae. 

 A winged viviparous female; B, apterous viviparous female. 



article III, four are visible on article IV, and two on article V. More are 

 likely visible from diiTerent angles, this simply being the usual number seen 

 looking down on the anteiuiae. Prothorax much wider than long and with 

 a distinct lateral tubercle on the lateral margins just back of the middle. 

 Rostrum — Lemon yellow in color with a dusky tip, reaching just beyond the 

 prothoracic coxae. Abdomen — Shiny black, well rounded and smooth, with 

 tew depressions to mark segmentation. Cornicles — Color, dark yellow or 

 amber, cylindrical, nuich longer than the style and several times as long as the 

 larsi. They gradually taper from the base to the tip. Legs — Moderately long 

 and hairy. The coxje and trochanters are black, tips of femurs and tips of 

 tibine, as well as entire tarsi are black, while the bases of the femurs and 

 tibije are lemon yellow. Wings — Of the normal Aphis type ; hyaline : stigma 

 long, narrow, and well pigmented. Length of primary 2 inm., width 0.0 



