SUBFAMILY APHINAE 251 
Collections. On Chrysothamnus viscidiflorus and on Gutierrezia sp. Utah: 
Holmes Creek, Cedar Springs and Curlew Valley. Alate and apterous viviparae 
June 9 and “viviparae” July 5; rather rare. 
Type. Knowlton Collection. Paratypes, Knowlton and Colo. ee Exp. Sta. 
Collections. 
This species is on the border line between Macrosiphum and Capitophorus 
but is placed in the latter genus on account of the presence on the vertex of 
fingerlike or narrowly infundibulate hairs, though globate to blunt hairs as in 
the former genus also occur. 
Chief Distinguishing Characters. Length of antenna (1.25 times as long as 
body), shape of the hairs (mostly fingerlike on vertex and body), absence of 
fingerlike hair on dorsum of cauda, length of cornicle (3-6 times as long as 
rostral IV+V). 
Capitophorus bitrichus Knowlton and Smith 
Capitophorus bitrichus Knowlton and Smith, 1936e:230. 
Apterous Summer Vivipara. (Mounted on slide), body immaculate; antenna, beginning 
with tip of V, cornicle, tarsi, rostral III and IV+V and tips of tibiae dusky; cauda, cornicle 
and anal plate pale to slightly dusky. Body length 1-1.28; across eyes .31-.35; antenna .95-1.15; 
hind tibia .47-.55; rostrum with needlelike tip, attaining 3d coxa. Hairs on vertex mostly 
broadened, but a few pointed, especially toward ventral aspect and with short sessile funnel- 
shaped ones dorsally; on body numerous and same as on dorsum of head; on antenna pointed 
and sparse; on hind tibia pointed and fairly numerous. Cornicle cylindrical. Cauda slender 
and tapering, bearing 2 pairs of lateral hairs. 
Jl 
Fig. 296. ee bitrichus 
Collections. On Artemisia tridentata, leaves and stems. Utah: Bear and 
Sardine Canyons, Hyrum and Lewiston. Apterous viviparae Aug. 4 to 23; 
apparently quite rare. 
Type and Paratype. Knowlton Collection. 
Chief Distinguishing Characters. Variation of hairs on the head of apterous 
vivipara, shortness of the cornicle (about the same length as base of VI), small 
cauda (on median line same length as base of VI), small size of body (length 
less than 1.30) and short antenna (shorter than 1.2, III not longer than .25). 
Capitophorus braggii (Gillette) 
The Oleaster Thistle Aphid 
Myzus braggii Gillette, 1908:17 and 1915b:375. 
Capitophorus flaveolus (Walker), Hottes and Frison, 1931a:282 Cais pured synonymy). 
Capitophorus braggii, van der Goot, 1915:119; Gillette and Palmer, 1934:146. 
On Cirsium arvense and Cynara sp. as summer hosts: 
Apterous Summer Vivipara. Pale greenish yellow to flesh-colored with greenish vittae; 
appendages, cornicle and cauda pale. Body length 1.9; hind tibia 1.25; cornicle .70-.90; 
antenna 2.33-2.7; rostrum attaining 2d or 3d coxa. Hairs capitate or globate; .06-.07 on vertex; 
slightly shorter on body and sparse; .01, merely blunt and sparse on antenna and hind tibia. 
Alate Vivipara. Head and thorax black or blackish; abdomen light yellow to greenish, 
with dark lateral areas and a dark green dorsal patch on III to VI. Other characters as in 
aptera except as figured. 
Male. Alate. Color as in alate vivipara except that on abdomen the dorsal patch is. 
broken into short bands which are present on all segments posterior to II. Body length 
1.50-1.80; antenna 2.10-2.30. 
Collections. On leaves and stems of Cirsium arvense and Cynara scolymus 
and C. cardunculus. Colorado: Fort Collins and Denver. Apterous summer vivi- 
