SUBFAMILY APHINAE 211 
Collections. On Artemisia tridentata. Utah: Brigham Canyon, Perry and Sar- 
dine Canyons. Apterous viviparae July 8; rare. 
Type. U.S.N.M. Paratypes, Knowlton and C. F. Smith Collections. 
Chief Distinguishing Characters. Abdominal VIII which is superimposed 
over the cauda, abundant broadly-funnel-shaped hairs on the body and heavy 
capitate ones on the tibiae, relatively short unguis (shorter than twice length 
of base of VI and hardly longer than third of length of tibia). 
Pseudoepameibaphis zavilla Knowlton and Smith 
Pseudoepametibaphis zavilla Knowlton and Smith, 1938d:221. 
Apterous Summer Vivipara. ‘Greenish; pulverulent’”; without dusky markings; ap- 
pendages pale except tips of tarsi and distal tips of antennal V and base of VI. Body length 
1.5-1.75; across eyes .40-.47; antenna .75-.85; hind tibia .50-.55; rostrum attaining between 
2d and 3d coxae. Cornicle and cauda typical. 
Fig. 247. Pseudoepameibaphis zavilla 
Collections. On Artemisia tridentata. Wyoming: Jackson Hole. Apterous 
viviparae June 12; rare. 
Type. Knowlton Collection. 
This species possesses longer cornicles than the other species of this genus 
here treated (over 2.5 times III and same proportion to unguis and 4-4.5 times 
base of VI). 
Genus Rhopalosiphum Koch 
Koch, 1854:23. 
Characters. Frontal tubercles hardly developed beyond vertex. Secondary 
sensoria circular, with narrow rims. Cornicle swollen, clavate, longer than en- 
tire length of cauda. Cauda parallel-sided or tapering. Hairs pointed or blunt. 
Wing venation as in genus Aphis. Living exposed on leaves and twigs of plants. 
Genotype (fixed by Gerstaecker, 1856), Aphis nymphaeae Linnaeus. 
Key to Species of Rhopalosiphum 
Pee Cormicie twice asiwidelin distal halfiasatibase: cx. scetesiecccsreccsse sete ceccee cece rset tan ones srpcngyoeeescsnceccers Pe 
Pemmcorniclenndistinctly swollensto neatly Cylindrical esses esceececac neces cect cct nee cae tna toeeatesoceasteanee 10 
2. Cornicle more than twice as wide in distal half as at base (p. 212).........2....----00----- berberidis 
Pe Gornicle not swollen:to(twice asiwide in distal) Hal fs ccez oe ececee occ sce gest ecrenene nee eeecbectasae anes 5 
Src Orniclersyinimetricaliy:s wollen (pis223) Mee eeqceece re cree reece tecsetceeeee cede tise cto eeasoceeeaeeoaeeee tenes serotinae 
POMC OTIC @ ANOreds WOllETi ONSITE G Var SIC Cee cesce nso oa a os set asp cpp dee neecc nas secseeicachoesstvacesnpunserecete 4 
4. Rostrum acute, with short needlelike Cpe page 2 8) cheep ae cen eee ce epee rufomaculatum 
wy, LEGOYSE ATA TD Ye Co) ab ab eet eo ok ie ee es a ee aie hate nee ees IE Abaes a oe nal soe ie UME SNP NEEE a RO eye Ts 1 ee me 5 
Su Pislongerithan.O5invalatas Longer tham 4 Oni ap telat cepts ence eet ek ae cae este aeene seetsee cee 6 
Pee shorter; thaneo5invalata, snorterstham .40\in apter ass cg enccetscreetnt cere te scene cates museca eetoes 7 
‘hy AOE Ba Pat iokerge 0 Gah, LUTE cree ce ee eee be hae Rete Sap is AE rer Pc teeta a RD Pras UR TAS Sept es grabhami 
ay OUST EEE) 1G GRID ae eR ar le ces ae oe ee ner Beare Ry atts eProp OE poae 
7. Sensoria not more than 12 on III of alata; cornicle longer than 
EMRE STEMMES MOSECA DEL Vist VCP sc Z2 Oi) retest diac as tee cos te eats See MMe a ped snes acest aamscteenae bade rhois 
Sensoria more than 12 on III of alata; cornicle not longer than 
PUIGPCETUITICCRCOSED Al BIN AV cece rere ese astern eer a Steins option er ete ere en A au fas MN nota ea ec sos ves Ande 8 
8. Rostral IV+V .15, coequal with hind tarsal II (p. 218) .0000.22...0...eetseeeeeseeeeeeeeteeeeee nym phaeae 
Serer MOGIf abi “Vee, SHOTLEr tran: hind farsa d TU casera arenes cen tescen acs ntact ketenapaadntbraretendaton 9 
9. III 1.5-2 times length of IV; sensoria fewer than 30 on III 
A ENCED w asceta sc utetcn. peal e oh ache dicots Ee baee tee pee Re 2 9 Nba A na A el pseudobrassicae 
III 2-3 times length of IV; sensoria more than 30 on III 
I AlACAw( Dice lS) ieee ace SoA ea er nee mem Se Renee SCN NRE 2 NG Ar) MR RES nid SLR lea ot toc e as conir 
