Distribution. California. 
Reference. Spencer, 1981: 137. 
2 ors, 4 ori P. prunivora Spencer 
Synopsis. Costa extending to just beyond apex of 
vein R 4+3, outer crossvein lacking; wing length 
from 2.5 mm in male to 2.75 mm in female; frons 
1.5 times width of eye; orbit distinctly project- 
ing above eye, increasingly so toward antennae; 
gena 0.20 height of eye; frons matt black, orbit 
and parafacial distinctly shining; mesonotum bril- 
liantly shining black; squama gray, margin and 
fringe black; male genitalia with aedeagus as in 
figures 467, 468. 
Host/Early Stages. Prunus lyonii , almost certainly 
other Prunus spp. Early stages unknown. 
Distribution. California. 
Reference. Spencer, 1981: 138. 
8 (2). Humerus yellow P. f lavohumeralis Sehgal 
Synopsis. Frons grayish black, equal to width of 
eye, at least slightly projecting above eye; 2 
ors, 2 ori; gena 0.125 height of eye, slightly 
yellowish; antennae entirely black; mesonotum 
matt, grayish black; humerus and upper margin of 
mesopleuron dull yellow; legs black, femora 
slightly yellow distally; wing length in male 
2.8-3. 1 mm (female unknown), costa extending 
strongly to vein M 1+2, last and penultimate 
sections of M 3+4 equal; male genitalia with ae- 
deagus as in figures 469, 470, with 2 distinctive 
patches of black pigmentation at end of distiphal- 
lus. 
Host/Early Stages. Unknown. 
distribution. California; widespread in Canada. 
References. Sehgal, 1968: 62; Spencer, 1969a: 106; 
1981: 136. 
Humerus dark 9 
9. Frons and antennae reddish orange 10 
Frons and antennae predominantly dark 11 
10 (9). Palpus yellow; small species, wing length in male 
2.5 mm P . pruinosa (Coquillett) 
Synopsis. Frons reddish brown, twice width of eye, 
strongly projecting above eye in profile; 5 orbital 
bristles, only upper ors reclinate, others in- 
curved; face and gena reddish yellow; epistoma 0.5 
height of that in P. betulivora (see fig. 473); 
mesonotum grayish black, with 3+1 strong dc, only 
about 3 rows of acr, prsc distinct; legs reddish 
yellow but base of femora, apex of tibiae, and en- 
tire tarsi brown; last and penultimate sections of 
vein M 3+4 equal, inner crossvein at midpoint of 
discal cell; male genitalia with aedeagus having 
distal tubules parallel, not diverging (fig. 471). 
Host/Early Stages. Unknown (misidentif ied as 
Betula nigra by Greene, 1914). 
Distribution. Colorado. 
References. Malloch, 1913a: 291; Frick, 1959: 376. 
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