194 APHIDS OF THE ROCKY MOUNTAIN REGION 
Genus Brevicoryne van der Goot 
Van der Goot, 1915:245; Das, 1918:179; Baker, 1920a:45. 
Characters. Body oval, lacking lateral tubercles on abdominal I and VII. 
Vertex moderately convex; frontal tubercles not distinctly exceeding vertex. 
Hairs pointed. Cornicle clavate, short, at most 3 times as long as broad, not dis- 
tinctly longer than cauda. Cauda tapering, never distinctly shorter than cor- 
nicle. Other characters as in Rhopalosiphum; separated from the latter only by 
the short cornicle, shorter than the hind tarsus and not longer than cauda. 
Genotype (monotypical), Aphis brassicae Linnaeus. 
Key to Species of Brevicoryne 
1. Unguis hardly longer’ than base-of VI (po 194) ooo ooo oases ne spaces cnc cree ceper esau ene nee eanee eae fraterna 
. Unguis twice or more’ times as long’as base Of (V Vic cioocecciecccse sc ecn ceca teen acevo eet eres eee eee 2 
2. III at least as long as IV+V, secondary sensoria absent on IV and V 
in ‘alata (pi 194) SFL e e Be ROT ear a eet ee ac brassicae 
... III shorter than IV-+V, secondary sensoria present on IV and V in 
alata. (pec 195) eres ee oo a cae eae ecco e are as eee ee symphoricarpi 
Genotype Brevicoryne brassicae (Linnaeus) 
The Cabbage Aphid 
Aphis brassicae Linnaeus, 1758:452; Herrick and Hungate, 1911:717. __ 
Brevicoryne brassicae, van der Goot, 1915:246; Theobald, 1927:45; Gillette and Pal- 
mer, 1932b:463. 
Apterous Summer Vivipara. Head dark brown, rest of body pale greenish with broken 
traces of dorsal bands on abdomen; powdery; otherwise as in alate vivipara. Body length 
1.8-2.15; hind tibia 1.15-1.25; antenna 1.2-1.9; rostrum barely attaining 2d coxa. 
om 
It => 41.5 
Px ° wg ? cz = pe y Ma fr 
ey z 
50 ~53 13-19 ‘ > 
Fig. 224. Brevicoryne brassicae 
Alate Vivipara. Head and thorax black; abdomen pale greenish with broken dashes of 
dusky and with dusky lateral areas; appendages, cauda, anal plate and cornicle dusky. Body 
length 2-2.3; hind tibia 1.4; antenna 2, secondary sensoria with distinct margins, somewhat 
tuberculate; rostrum not attaining 2d coxa. Hairs pointed. Cornicle swollen, slightly wider 
at middle than hind tibia. Cauda tapering, acute, bearing 2 pairs of lateral and one pair of 
dorsal hairs. 
Ovipara. Apterous. Color same as apterous vivipara or more yellow and legs paler. 
Body length 2; antenna .83-1.20; hind tibia moderately swollen and bearing small, rather 
sparsely scattered sensoria throughout almost entire length. 
Male. Alate. Body length 1.40: hind tibia .90; hind tarsal II .18; antenna 1.50, III, IV 
and V bearing numerous sensoria. 
Collections. On cabbage (Brassica oleracea), cauliflower (B. 0. var. botry- 
tis) and radishes (Raphanus sativa). Throughout region. Fundatrices Feb. 3 to 
April 8, apterous and alate viviparae every month in the year, males Oct. 27 to 
Dec. 6, oviparae Nov. 13 to Feb. 21; common and injurious. 
Brevicoryne fraterna (Strom) 
Aphis fraterna Strom, 1938:473. 
Brevicoryne salixutis Smith and Knowlton, 1940:405 and 1943:175 (synonymy). 
Apterous Summer Vivipara. Pale green to yellow-green; all appendages pale, except 
tips of tibiae, entire tarsi and distal third to half of antenna. Body length 1.2-1.45-“1.75”; 
across eyes .35-.47; antenna .53-.73; hind tibia .45-.57-‘..72’’; rostrum attaining between 2d 
and 3d coxae. 
Alate Vivipara. (From description by Strom). Color as in aptera. Body length 1.1; 
across eyes .35; antennal III .14 with 3 sensoria, IV .07, V .08, VI .07+.065; cornicle .12, 
somewhat swollen and with marked constriction just preceding flange; rostrum attaining 3d 
coxa. Cauda tapering bearing 2-3 hairs on each side. 
