SUBFAMILY APHINAE a 
shining brown; abdomen green with dusky spots at bases of hairs; more or less mealy; an- 
tenna brown to black; legs dusky yellow; cornicle dusky; cauda green. Body 2-2.5 long; 
linear; ocular tubercle lacking; hind tibia 1.7-1.8; hind tarsal II 21; antenna 1.2-1.3, III 
-39, IV .21-.24, V .25, secondary sensoria absent. Fore wing with media faint, usually once- 
branched. Cornicle a mere raised ring. Rostrum obtuse, IV .07, V -015, attaining 2d coxa. 
Hairs long, spinelike; on vertex .08-.12; on body .02-.03; on antennal III -03-.07; on hind 
tibia .08-.11. 
Apterous Summer Vivipara. Same as alate vivipara in color and measurements. 
Collections. On tender needles of Pinus sylvestris. (Not recorded from 
region.) 
Data for above description and figure taken from Kaltenbach (op. cit.) 
and from specimens determined by van der Goot, Hille Ris Lambers and 
H. L. G. Stroyan. 
Theobald (1929:122) and Del Guercio (1909a:317) describe III of alate 
vivipara as bearing sensoria. Hille Ris Lambers states in correspondence that 
three species were confused in these descriptions, one of which, Eulachnus 
brevipilosus Borner possesses sensoria on III. Not figured on account of sim- 
ilarity to Eulachnus rileyi (Wiliiams). 
Eulachnus rileyi (Williams) 
The Powdery Pine Needle Aphid 
sen.oO 
35-42 -.50 
Hind tarsus 
Cormiecle fp 
R Ra1o-- 4 
Hind tibia 
Fig. 11. Eulachnus rileyi 
Lachnus sp. near agilis, Gillette, 1909c:385. 
Lachnus rileyi Williams, 1910:24. 
Eulachnus riley1, Davis, 1914a:169; Knowlton, 1930:158; Gillette and Palmer, 1931:836. 
Apterous Vivipara. Olive-brown; somewhat powdery; cornicle black; legs dark. Body 
2-2.6 by .6; hind tibia 1.5-2; hind tarsal II .21-.25; antenna 1.2; cornicle mere ring without 
conical base. Cauda usually appearing rounded but with upturned tip, when extended ap- 
pearing pointed. 
Alate Vivipara. Same as apterous vivipara in measurements. Secondary sensoria absent 
in III, 1 on IV. Hairs heavy, .10 long, spinelike on vertex; sparse and inconspicuous on 
body; moderately numerous on appendages, on hind tibia, twice or more as long as diameter 
of tibia. Rostrum broad, obtuse, attaining 3d coxa. Fore wing with media faint, usually 
once-forked, rarely simple. 
Ovipara. Apterous. Same as apterous vivipara except that hind tibia is 1.30-1.65 long 
with proximal half moderately swollen and rather thickly covered with flat sensoria. 
Male. Alate. Same as alate vivipara except antenna which is longer, about 1.75, III 
-55-.65, IV .32-.37, V .35-.37, VI .17-.21+.03-.04; secondary ssnsoria numerous on III and IV, 
12-21 on V, and 0-4 on base of VI. 
Collections. On Pinus ponderosa var. scopulorum and P. palustris, on 
needles. Colorado: Denver. Utah: Salt Lake City, Plain City and Logan. 
Apterous and alate summer viviparae June 20 to Sept. 5, sexuales Sept. 24 to 
Oct. 7; rare. 
Type. U.S.N.M., No. 79. 
This species is very similar to E. agilis but is here retained as distinct 
on account of the following: Brown body, slightly longer antenna and hind 
tibia and different host. None of these characters are clearly distinctive but 
until further study proves them invalid it seems best to retain Williams’ name. 
