336 APHIDS OF THE ROCKY MOUNTAIN REGION 
Alate Vivipara. Color same as in apterous vivipara. (Cleared and mounted), head and 
thorax dark; abdomen with dark lateral areas and sometimes dorsal patch evident; antenna 
and cornicle black, cauda and anal and genital plates dusky. Body length 1.4-1.6; across eyes 
.37-.39; hind tibia .93-1; antenna 1.7. Rostrum attaining 2d coxa. Hairs capitate, very sparse 
and inconspicuous; on vertex, antenna, hind tibia and on side of abdomen .01. Cornicle cylin- 
drical, less tapering and curved than that of apterous vivipara. Cauda tapering to nearly 
cylindrical and bearing 2-3 pairs of lateral hairs. Otherwise as in apterous vivipara. 
Ovipara. Apterous. Body length 1.10; across eyes .35; antenna .80-.85; hind tibia with 
proximal half slightly swollen and bearing about 20 sensoria. ; 
Male. Alate. Deep black; abdomen may be dusky brown with dorsal bands and becom- 
ing black between and posterior to cornicles; antenna and cornicle black; cauda and rostrum 
dusky; tibiae yellow. Body length 1.30; antenna 1.70, sensoria tuberculate; hind tibia 1.1. 
Collections. On leaves and twigs of sweet cherry (Prunus avium) and sour 
cherry (P. cerasus) and rarely plum, curling leaves (no alternate host plant 
proven for this region)*. Throughout region. Fundatrices April 14 to 27, apterous 
summer viviparae May 10 to Nov. 2, alate viviparae June 8 to Nov. 2, sexuales 
Nov. 2 to 17; common, in large colonies, often injurious. 
Funda- ane aa Co F. ..25-.35 4 
trix ea LARA HAIN LD UUW EAronireee mere : PIII ANGI! Be 
a ; (4-16) AO J30 0 ie 0) Da ated “5 9 9 9h 919 Pye Nga 
EP Pree TS ree) 5 
Apt 
Vis 
SIP 
2-14) 23-4) Tae 
Co TTR) eae 
(32-45) 423 5 
Te AOA ee eee 
aii Ti (37 =55) 
a 
eA a eda 
Fig. 403. Myzus cerasi 
Chief Distinguishing Characters. Shiny black body and appendages except 
tibiae which are yellow, absence of sensoria on IV of alate vivipara, short hind 
tarsus (.09, shorter than base of VI) and hind tibia of ovipara only the proximal 
half of which is swollen, and that slightly, and bearing scattered large sensoria. 
The form here described may not be the same species which W. A. Ross 
(1917:434) found migrating to Lepidium sp. as summer host. At least alate spec- 
imens, about ten, from sweet cherry loaned by Ross showed sensoria on IV 
which character has not been found in specimens here, nor has it been found 
in numerous alate viviparae sent by Robt. D. Eichmann. Eichmann (op. cit.) 
failed to find the species migrating to Lepidiuwm; nor did he locate it on any 
-summer host though the aphids disappeared from the cherry. These observa- 
tions suggest a possible taxonomic difference. In Colorado the sweet cherry has 
not been seriously attacked; though the species does infest both sweet and sour 
cherry and experimental transwers from sour to sweet cherry have succeeded 
well. 
Myzus circumflexus (Buckton) 
The Crescent-marked Lily Aphid 
Siphonophora circumflexa Buckton, 1876:130. 
Myzus vincae Gillette, 1908b:19. 
Macrosiphum circumflexum, Theobald, 1913b:116. 
Myzus circumflexus, Theobald, 1926:331; Gillette and Palmer, 1934:202. 
Apterous Summer Vivipara. Yellow-green with blackish U-shaped dorsal patch on ab- 
dominal II to V and a pair of dorsolateral patches on thoracic segments; all appendages pale 
to brownish; antennal VI and tips of III, IV and V and tip of cornicle blackish. Body length 
1,5-1.7; across eyes .39-.43; hind tibia 1.1-1.75; antenna 2.4-2.5; rostrum attaining nearly to 3d 
coxa. Hairs capitate; on vertex, III, hind tibia and marginal row on abdomen .01. Cornicle 
cylindrical, slender. Cauda tapering to nearly cylindrical and bearing 2-3 hairs on each side. 
*Record by Gillette (1918d:241) proved to be only accidental. The aphids have been 
ound on cherry throughout the summer though in suddenly reduced numbers after 
early July, and an increase in alate forms has been recorded at the end of August and 
especially by the middle of September. 
