178 APHIDS OF THE ROCKY MOUNTAIN REGION 
Alate Vivipara. Head and thorax black; abdomen greenish or brownish black, mounted 
specimens showing dorsal dusky bands on abdominal I, VI, VII and VIII and more or less 
on the remaining segments; antenna, cornicle, cauda and rostrum dusky to blackish; legs 
sordid yellow with black at tips of segments. Body length 1.49-4.60; hind tibia .75-.80; antenna 
1.25, secondary sensoria slightly tuberculate and strongly convex; rostral IV+V broad, width 
at base equal to half the length, attaining between 2d and 3d coxae. Hairs slightly capitate, 
semierect; .02-.03 long on antenna, vertex and hind tibia. Cornicle cylindrical, smooth, with 
large flange preceded by groove. Cauda tapering, acute, broader than long, bearing two pairs 
of lateral hairs and a single dorsal preapical hair. Lateral tubercles present on abdomen but 
shallow and difficult to observe. 
Fig. 203. Aphis solidaginifoliae 
Ovipara. Apterous. Reddish black, mounted spécimens showing dusky dorsal bands on 
all segments, sometimes coalesced; antenna, cornicle and cauda blackish; legs mostly yellow. 
Body length 1.60-1.70; antenna .85; hind tibia slightly swollen on proximal half which portion 
bears about 18 large sensoria. 
Male. Apterous. Color same as in ovipara, Body length 1; antenna .82; cornicle .08; hind 
tibia .62. 
Egg. Newly laid, pale honey-yellow; later, shining black. Size .66 by .35. 
Collections. On Solidago sp., in leaves folded on midrib, appearing podlike. 
Colorado: Fort Collins. Idaho: Berger and Castleford. Apterous summer vivi- 
parae July 16 to Sept. 26, alate viviparae July 9 to Sept. 26 (scarce), oviparae 
Sept. 18 to Oct. 14, males Sept. 18 to 26; rather common. 
Cotypes. Univ. of Neb. Collection, Nos. 91 and 92 and U.S.N.M., No. 111. 
Chief Distinguishing Characters. Peculiar acute shape of the cauda with 
only 2 pairs of lateral hairs, tuberculate shape of the secondary sensoria, pres- 
ence of sensoria on III, IV and V in both alate and apterous viviparae, rather 
broad rostral IV+-V and hind tibia of the ovipara which is only slightly swollen 
with rather few sensoria. 
Aphis sorensoni Knowlton 
Aphis sorensoni Knowlton, 1928b:169. 
Alate Vivipara. Head and thorax black; abdomen bluish green; antenna, cornicle, cauda, 
tarsi and tips of tibiae black; fore wing with veins typical.* Body length 1.55; across eyes .43; 
hind tibia 1; hind tarsal II .13; antenna 1.20, III .36, IV .23, V .20, VI .11+.35, sensoria 25-30 
on III; cornicle .25; rostral IV-+V .12 attaining barely to 2d coxa. Cornicle cylindrical and 
imbricated. Cauda spatulate, bearing 4-5 pairs of lateral hairs and one dorsal preapical one. 
Collections. On‘ Salix lutea (a single alate specimen without progeny; 
possibly accidental). Utah: Providence. Alate vivipara July 18. 
Type. Knowlton Collection. 
This specimen is very close to A. helianthi and not certainly distinct, dif- 
fering only as follows: Slightly longer unguis (.35 instead of .25-.30) and longer 
tibial hairs (.03 instead of .01-.02). 
*Described in original description as “slightly dusky” but this coloration was not 
noticeable on type specimen when examined by the writer in 1945. 
