SUBFAMILY APHINAE 289 
55. Cornicle with reticulated area extending for more than third of length (p. 294)........ atripes 
... Cornicle with reticulated area extending less than third of length (p. 315)................ martini 
56. Rostral IV+V longer than .14; sensoria 27-32 on III of alata (p. 290).......... agrimoniellum 
.-.- Rostral IV+V not longer than .14; sensoria 10-28............2.:c--:scscscsssssccsssssocensstesceneesecenenes Cae es 57 
57. Antenna beyond base of III heavy and black; sensoria 13-18 on III 
PE ER A EU GS SAU see rg 8 nae Poem rs an res Sn let Rf ee pseudorosae 
... Antenna beyond III dusky; sensoria 16-17 on III of alata (p. 289)...........-..... aetheocornum 
... Antenna pale; sensoria 18-28 on III of alata (p. 316)....................csscsceessceeeseseeesceneeoee mertensiae 
eo se Unguis distinctly longer: than LV (Gps 296) coric.cxcoctepseced covert enone tevecipe ec evekctydoceeeeternens breviscriptum 
BULITSULS COCCUAL Withi el. Vir CDs GOA) ctirce ates rec tenes ets ra cece aeons oreo nee can eee zymozionensis 
59. Cornicle not longer than entire length of cauda; rostral IV+-V .13; 
Sensoriare4-ss on el 11 Of alata (p13 25) cerecners saccese reeset ie scat ct Sacra ce ee cecat een ct tesa eed ont ccee sansa’ sanborni 
..- Cornicle longer than entire length of cauda; rostral IV-+V longer than .13; 
RONROLIA Ot LOWET tial 35 OD) LL LOL ala ta ox c.cs eee sense kets cc casege od ets her sabe eeeniadorescensieesnins se wr 60 
OOmenostrale LV V 2-15 longs CORnicle:-4.5-.00) (pp. 298) sscce ce cace as eeeec ane ces soecctaceeeencs sescessed chrysanthemi 
Rostralelv-toVe.l 7 long ss COrmiclés. 082: 7.19 (Dip 269) oescesse nc ncsse seca wrens te mancencseoesceaetorces sat tere aaroni 
Macrosiphum aaroni Knowlton 
Macrcsiphum aaroni Knowlton, 1947d:47. 
Alate Vivipara. ‘‘Black to blackish”; (Cleared and mounted), head and thorax brownish; 
abdomen colorless with dusky areas at bases of dorsal hairs and with dark lateral areas on all 
segments except I; antennal I and II dusky, remainder including base of III black; almost 
entire legs, distal rostrum and entire cornicle black; cauda and anal plate pale. Body length 
2.63; across eyes .54; antenna 3.67, III .85-.89, IV .71-.75, V .65-.68, VI .15-+-.95-“1.01"; sen- 
soria 34-40 on III; cornicle .68-.71, with reticulated area ‘‘.16’’-.20 long; rostrum slightly sur- 
passing 2d coxa. Cauda slender and tapering, with slight neck, .42 long on median line, .50 on 
side and bearing 7-8 pairs of lateral hairs and a single dorsal preapical one. 
Collections. On Chrysothamnus nauseosus subsp. nauseosus. Utah: Honey- 
ville. Alate viviparae Sept. 13; rare. 
Chief Distinguishing Characters. Black body with antenna, legs beyond 
_ bases of femora and cornicle black or blackish throughout, length of reticulated 
area on cornicle (not longer than .20), number of sensoria on III of alate vivi- 
para (over 30) and number of hairs on cauda (7-8 pairs of lateral ones). 
This species differs from M. ambrosiae only in the shorter reticulated area 
on cornicle (not .25-.30). 
Not figured on account of similarity to M. ambrosiae. 
Macrosiphum aetheocornum Smith and Knowlton 
Macrosiphum aetheocornum Smith and Knowlton, 1939:241; Knowlton, 1940a:197. 
Apterous Summer Vivipara. ‘‘Greenish.” (Cleared and mounted), body pale without dark 
areas at hair bases; tibiae and cornicle pale with dusky tips; tarsi and antenna beyond III 
blackish; cauda slightly dusky. Body length 3-3.4; across eyes .50-.53; antenna 3.8-3.98; hind 
tibia 2.2-2.8; rostrum attaining 3d coxa. Cauda tapering, bearing about 4 pairs of lateral hairs 
and 1-2 preapical ones. 
Viv. 64 ."97-102" $en.6-9 
a ae “10 
Fig. 343. Macrosiphum aetheocornum 
Alate Vivipara. (Mounted), head and thorax brownish; abdomen pale; tarsi, tips of 
tibiae, rostral IV+-V, tip of cornicle and antenna beyond base of III dusky; cauda pale. Body 
length 2.2-“‘2.65”; antenna 4.5; hind tibia 2.35; rostrum attaining 3d coxa. 
