8 APHIDS OF THE ROCKY MOUNTAIN REGION 
EXPLANATIONS 
Quotation marks enclose data quoted from the original descrip- 
tion which were not verified in typic material studied by the author 
of this work, but might exist in other cotypes or paratypes observed 
by the author of the species. Measurements are given in millimeters. 
Body length is taken from vertex to base of cauda. Base of antennal 
VI is here considered to extend to the base of the unguis, thus to 
include the entire permanent sensorium (except in Essigella). 
Descriptions of color refer to the dorsum only, unless otherwise 
stated. Antennal segment measurements are given in limits of varia- 
tion not in exact proportions of any certain individuals since only 
inside the limits of variation do proportions hold true. This may be 
observed by study of tables of measurements. Frequently the long- 
est limit of one segment may be found in the same antenna with the 
shortest limit of another segment (Bachelder 1927:263). Hairs on 
hind tibia refer to those on the dorsal side in the middle region. 
Measurement of cauda is made on median line, hard portion, unless 
listed for side. 
Collection dates are more or less accidental findings; little in- 
tensive work on limits of occurrences has been done. Keys are con- 
structed as far as possible on characters applying to both alate and 
apterous viviparae unless otherwise stated, designated as alata and 
aptera respectively. 
TAXONOMY 
Key to Subfamilies of Aphidae 
1. Antenna, cauda or cornicle or all three well developed; wing veins not reduced, 
media once or twice-branched (Fig. 1); sensoria on antenna circular or oval; wax 
glands not abundant, rarely present. Living naked and exposed on plants, 
sometimes in curled leaves, rarely om roots. (p. 8) z-ccecccccecceccneetotenseeeceeee eee Aphinae 
Antenna more or less short, especially in aptera; cauda inconspicuous and cornicle 
a mere pore or wanting; wing veins reduced, media only once-branched or simple. 
(Fig. 421 and 436); sensoria on antenna usually transverse or annular (Fig. 421 
and 449), rarely circular; wax glands often abundant. Living concealed under 
flocculent secretions, in folded leaves, in galls or underground on roots (except 
Mindarusy 2.222 ce oe RA hn ees ak siete ee 2 
2. Radial sector arisink at proximal end of stigma; cauda somewhat produced, 
not knobbed. Living exposed. “Cp. 346) eee Mindarinae 
Radial sector arising from stigma, usually near distal end (Fig. 421); cauda either 
semilunar (Fig. 421) or knobbed (Fig. 455). Living usually concealed under 
flocculent secretions, in folded leaves, in galls or on roots; wax glands usually 
NUM OT OUS:. s2.--cccece gd es vacances asc somu tatters wa vee gst 0e bse ie ce RU eee oe ee aca ene te 3 
3. Sexuales without functioning mouth parts; ovipara laying a single egg; cauda semi- 
lunar; anal plate entire. Aleyrodiform stages not developed (p. 347).........-.. Eriosomatinae 
Sexuales with functioning mouth parts; ovipara laying several eggs; cauda 
knobbed; anal plate bilobed. Aleyrodiform stages common (p. 376).......--------- Hormaphinae 
Subfamily Aphinae Gillette and Palmer 
Gillette and Palmer, 1931:830. 
Characters. Cornicle evident, either as a cylindrical or clavate tube or as a 
raised rim, usually on mammiform base, rarely absent; cauda usually well 
developed (except in Lachnini and Chaitophorini in part, in Phyllaphina and 
in Amphicercidus). Compound eye developed in aptera; antenna always longer 
