SUBFAMILY APHINAE 141 
This species resembles A. maidi-radicis but differs as follows: Unguis 
usually shorter than 1.5 times length of V and not longer than rostral IV+V, 
hind tibia less than half of the body length and in ovipara not swollen and 
not crowded with numerous sensoria and body not marked with dusky spots 
and dashes. However, some few viviparous individuals which fit these specifi- 
cations occur among typical individuals of A. maidi-radicis in collections from 
corn roots. 
This name may be a synonym of maidi-radicis but due to the small num- 
ber of specimens and lack of alatae, from Gutierrezia, for study it seems best 
not to make a decision at this time. Further study of oviparae is needed to 
determine whether variability in swelling of the hind tibia may obliterate the 
apparent distinguishing difference in that character. Knowlton states that no 
injury to corn by root-louse was reported in the same lccality at the same date. 
Aphis helianthi Monell 
The Dogwood or Sunflower Aphid 
Aphis helianthi Monell, 1879:26; Gillette, 1927:346; Hottes and Frison, 1931a:196; 
Gillette and Palmer, 1932b:402. 
Aphis oxybaphi Oestlund, 1887 :62. 
Aphis gillettet Cowen (in Gillette and Baker), 1895:120. 
Aphis cornifoliae Fitch (misidentification), Gillette, 1910:407. 
Fundatrix. Color similar to summer aptera or darker green with lighter mottling and 
covered with slight powder; appendages pale yellowish with tarsi and tips of appendages 
black; cornicle dusky distally. Body length 1.60; antenna .60, five-segmented; hind tibia .53. 
Apterous Summer Vivipara. Head yellow-brown; rest of dorsum yellowish green mot- 
tled with medium to dark green and with dark green band on anterior portion of abdominal 
V; tibiae pale yellowish with tips of tibiae and tarsi black; cornicle black; cauda, anal plate 
and venter of abdominal VIII dusky. Body length 1.5-1.9; hind tibia .85-.90; antenna 1.1-1.3; 
cauda spatulate to parallel-sided; rostrum attaining 2d coxa. 
d- TODOUCUARID eH! 5 400) ae A Co 
ine 8 6 08.07. 10 f) ap ARH Aehng 
CT, raat 
117 =.20 
17-307) 
Vy yy db ythyy 
wy) fu 
BONO ar eT aaa 
Fig. 156. Aphis helianthi 
SND POS b'0'0'0, 
Alate Vivipara. Alatoid Nymph. Yellowish brown to green; tessellated. Adu/t. Head 
and thorax black; abdomen pale yellowish green, often with darker green band on abdominal 
V, with lateral areas, especially blotch behind cornicle ard sometimes traces of darker to 
dusky dorsal bands especially on segments VI, VII and VIII; covered with very slight 
powder; cornicle, rostrum, cauda, anal plate, genital plate and antenna dusky to blackish; 
legs pale yellowish with tips of tibiae and tarsi dusky. Fall migrant often yellow-brown. 
Measurements same as in aptera except as figured. Secondary sensoria slightly convex, 
hardly tuberculate. Cauda bearing 5-6 hairs (in some cases only 3-4 evident) on each side. 
Hairs pointed, drooping, sparse, and short. Lateral tubercles evident on prothorax and ab- 
dominal I and VII. 
Ovipara. Apterous. Head yellowish brown; body yellowish to dusky green, mottled 
with eggs showing through body wall; appendages except tips of segments, colorless and tarsi 
black; hind tibia pale to dusky, distinctly swollen and bearing numerous sensoria. Body 1.25; 
antenna .64-.77 often five-segmented. 
Male. Alate. Head and thorax black; abdomen yellow-brown. Body length about 1.20- 
1.50; antenna 1.44. 
Egg. Newly laid, pale greenish yellows later, black, shining. Size .60 by .24. 
