224 APHIDS OF THE ROCKY MOUNTAIN REGION 
Chief Distinguishing Characters. Unusually long erect hairs especially in 
aptera, extremely frequent fusion union of [II and IV and body color (green 
with red about cornicle bases). 
This species belongs to the R. fitchii-padi complex. For this group winter 
hosts are apple, Crataegus, Prunus, Scirpus and Typha. These plants were very 
rare or entirely absent in the infested localities and the aphids were apparently 
maintaining themselves in the viviparous state on the wheat as no sexuales 
were taken nor were there any great numbers of fall migrants evident. The 
specimens present were nearly all apterous. 
A ee 
2196 12248 £ coq 
“i yey PROUT Ra ited 
Late <_ 2), Paes ees 
Le Rostrum ©(s) ) 
D - 99 J 
Co. se Saves A 
= . : i 
5 wa wn. { 
) 
I 
NUR 
) 
}? 
2.0 tiv, 
i) < be 
wor HT 
1 : AlateViv. 
Rhopalosiphum splendens 
The form here described differs in the frequently five-segmented antenna 
from Theobald’s description (where only a six-segmented condition is men- 
tioned) and in the often six-segmented antenna from Mason’s. (1937:166) de- 
scription of Rhopalosiphum subterraneum (where only a five-segmented con- 
dition is described) also from the latter in green body with red coloration about 
cornicles instead of brown body. Further study of variations in these two forms 
may prove R. subterraneum Mason to be a synonym of R. splendens (Theobald). 
Rhopalosiphum subterraneum Mason 
Rhopalosiphum substerraneum Mason, 1937 :166. 
Cerosipha californica, Essig, 1944:177. 
This species may be the same as R. splendens, as the only difference seems 
to be the color in life. Body color in R. splendens, apterous vivipara and nymph, 
is “green with bright dark crimson about cornicle bases, sometimes obscure 
orange on abdomen.” Body color in R. subterraneum is “brown” or possibly 
“grayish green,” without’ mention of red coloration in descriptions by either 
Mason or Essig. 
Collections. On roots and crown of wheat. Colorado: Bristol. Apterous 
viviparae Nov. 2; apparently rare but usually abundant and injurious where 
occurring. 
Type. U.S.N.M. Cerosipha californica Essig, Essig Collection. 
Genus Siphonatrophia Swain 
Siphonatrophia Swain, 1918a:363; Baker, 1920a:51. 
Minuticornis Knowlton, 1928c:60. 
Characters. Frontal tubercles rudimentary; vertex convex. Antenna five- 
segmented in at least fundatrix and ovipara.* Secondary sensoria circular. 
Body of aptera strongly arched dorsally, flattened ventrally, hemispherical. 
Cornicle a slightly raised pore. Cauda elongate-tapering, ensiform. Fore wing 
with media once or twice-forked. Hind wing with both media and cubitus. 
Lateral tubercles not evident. 
Genotype (monotypical), Cerosipha cupressi Swain. 
*The five-segmented antennal character appears to be of minor importance upon con- 
sideration of its variability in S. gravida Knowlton. Knowlton’s form shows such 
striking agreement in all other characters except branching on media, that even 
specific distinction is somewhat uncertain. 
