310 APHIDS OF THE ROCKY MOUNTAIN REGION 
Macrosiphum granarium (Kirby) 
The English Grain Aphid 
Aphis granaria Kirby, 1798:238. 
Siphonophora granaria, Buckton, 1876:114; Pergande, 1904:14. 
Macrosiphum granarium, Phillips, 1916: 463; Theobald, 1926:71; Gillette and Palmer, 
1934:182. 
Apterous Summer Vivipara. Grass-green, sometimes yellow or pink, brown on head, 
frequently with dusky dorsal blotch on abdomen; entire cornicle and antenna dusky to black; 
cauda, anal plate and tibiae pale. Body length 1.9-2.5; hind tibia 1.35-1.9; antenna 2.6-3.3; 
rostral IV+V very broad and blunt, half as broad as long, tip attaining beyond 2d coxa. Hairs 
pointed to blunt; on side of abdomen .02-.03. Cauda spatulate, rather slender, bearing 3-4 
pairs of lateral hairs and two dorsal preapical ones. 
Apt. ge 
viv a oa ST 5 Vb 
soa Ys eS 
SUE Ore 
- 2 
i aL 
os epee ee Al. = Apt. Vii 
AIDS L220 0 0S 2008 OOS SED aS 
Fig. 368. M 368. Macrosiphum granarium 
Alate Vivipara. Head and thoracic lobes yellowish brown; abdomen grass-green or pink, 
with darker green on median line and lateral areas and without dorsal blotch. Otherwise as in 
apterous vivipara except rostrum hardly attaining 2d coxa. 
Male. Alate. Same in color as alate vivipara or more brownish. Body length 1.60-2; 
antenna 2.9, sensoria numerous on III, 16 on IV, 12 on V; hind tibia 1.33; cornicle .30. 
Collections. On leaves and heads of oat, rye, barley, wheat, Elymus sp., 
Heracleum sp., Linum sp. and Kentucky bluegrass (Poa pratense). Throughout 
region. Apterous and alate summer viviparae May 8 to Nov. 8, males Sept. 16 
and Oct. 26; common. 
Chief Distinguishing Characters. Grass-green or pink body with frequent 
dorsal blotch in apterous and darker median line in alate vivipara, short broad 
rostral IV-+V (width at base equalling length), comparatively short cornicle 
(shorter than III), length of reticulated area on cornicle (extending fourth to 
third length of cornicle), rather short, spatulate cauda (on median line 2-3 
times, or in aptera occasionally 4 times, length of rostral IV+-V), small number 
of sensoria on III (7-12 in alate vivipara, 1-2 in aptera). 
Macrosiphum idahoensis Miller 
Macrosiphum idahoensis Miller, 1933:249; Palmer, 1936b:745. 
Alate 
Viv. 
(75-110) 
PALES Hd. ee 
ae 
IS=/7 
Snare 369. Macrosiphum idahoensis 
Apterous Summer Vivipara. Light green to creamy white; appendages brown except 
cauda which is green. Body length 2.32; across eyes .48; antenna 2.5; hind tibia 1.5; rostrum 
attaining 3d coxa. Cauda tapering to rather acute point but with construction near base and 
bearing 6-7 pairs of lateral hairs and about 3 dorsal ones. 
