290 APHIDS OF THE ROCKY MOUNTAIN REGION 
Collections. On wild geranium (Geranium sp.). Utah: Logan, Allen and 
Card Canyons. Apterous viviparae July 18 to Aug. 1, alate viviparae June 16 to 
July 18; rather rare. 
Chief Distinguishing Characters. Presence of reticulation on the cornicle, 
length of antenna and cornicle, number of sensoria on III of alate vivipara 
(more than 8) and presence of hairs on the cornicle. 
Macrosiphum agrimoniellum (Cockerell) 
Nectarophora agrimoniella Cockerell, 1903a:168. 
Alate Vivipara. ‘‘Light apple-green, without markings”; cornicle beyond base, antenna 
beyond base of III, rostral IV+-V, tarsi and tips of tibiae blackish; cauda and anal plate pale. 
Body length 2.5-3.2; across eyes .51; antenna 4.5; hind tibia 2.4-2.5; rostrum attaining 2d coxa. 
Cauda slender, tapering, but with slight neck. Hairs blunt to slightly capitate on vertex and 
antennal III; blunt to pointed on hind tibia. Cauda with 4-5 pairs of lateral hairs and one 
preapical one. 
02-83 = "90" 
if-Lb5+t 23" 
16 [3= 
by Hd.Ta. a vp type Pay. Ep voraanon iss) 
: os Dy <= : —" Wy 
ae | R, a gee 
Fig. 344. Macrosiphum agrimoniellum 
Collections. On Agrimonia eupatoria on flower stalks. New Mexico: 
Beulah. Alate viviparae July 27; very abundant on infested plants. 
Type. U.S.N.M. 
Chief Distinguishing Characters. Light green body, length of III, and of 
unguis (at least 1), absence of capitate hairs on tip of cauda, number of sensoria 
on III in alata (about 30) and extent of reticulated area on cornicle (.13-.15). 
Macrosiphum albicornum Knowlton and Allen n. comb. 
Mucrotrichaphis albicornus Knowlton and Allen, 1940:33. 
Alate Vivipara. “Black; antenna beyond proximal half of III and cornicle dusky.” Body 
length 2; hind tibia 1.15-1.3; tarsal II .14-.15; antenna about 2.3-2.4, III .62-.66, IV .40-.43, 
V .37-.42, VI .13-.14+.65, sensoria 12-16 on III; cornicle ‘‘.45’’-.51, with reticulated area .07-.09; 
cauda .25-.30 on median line, .30-.35 on side; rostral IV+-V .13-.15, attaining 2d coxa. Frontal 
tubercles shallow. Hairs pointed to blunt; .03-.04 long on hind tibia. Cauda spatulate, bearing 
about 4 pairs of lateral hairs and one preapical one. 
Collections. On Artemisia tridentata. Utah: Cache National Forest, Cedar 
Valley, Logan Canyon, and Smithfield. Alate viviparae May 10 to Aug. 23; not 
common. ; 
Type and Paratypes. Knowlton Collection. 
This form known only from the alate vivipara agrees so closely in color 
and measurements as well as in hairs with the aptera of M. zerothermum that 
it seems impossible to draw a line of distinction. They, indeed, do differ from 
the few alatae in longer antenna and cornicle; so they are here retained as dis- 
tinct awaiting further information as to the range of variation in alatae in the 
latter species. 
Not figured on account of similarity to M. zerothermum. 
Macrosiphum albifrons Essig 
Essig’s Lupine Aphid 
Macrosiphum albifrons Essig, 1911c:543; Soliman, 1927:108; Gillette and Palmer, 
1934:171; Knowlton, 1935a:114. 
Apterous Summer Vivipara. Bluish green, pulverulent; cauda pale; cornicle pale except 
tip; appendages pale to slightly dusky with tips blackish; tarsi black. Body length 3.20-4.20; 
hind tibia 2.50-3; hind tarsal II .18-.20; antenna 4; rostrum surpassing 2d coxa. Hair slightly 
capitate; .05 on side of abdomen. Cornicle cylindrical, reticulated at tip. Cauda ensiform, 
bearing 7-8 pairs of lateral hairs and 2 dorsal preapical ones. 
