1973 ] 
Evans — Neotropical Pompilidae 
219 
tance; vertex strongly elevated above eye tops, especially at ocellar 
triangle; postocellar line: ocello-ocular line — 2:1; third antennal 
segment 7.5 X as long as its apical width, 1.1 X upper interocular 
distance (Fig. 3). Pronotum short, disc sloping and with no flat 
dorsal surface; postnotum transverse, not projecting backward medi- 
ally. Wing venation similar to that of variegata but stigma unus- 
ually wide, third submarginal cell smaller, only 1.5 X as wide as 
high, removed from wingtip by twice its own width. 
Dimorphagenia, new genus 
Type-species. — D. naumanni, new species. 
Generic characters. — With the general features of the Auplo- 
podini, including the wing venation (shown in Fig. 4) and the form 
of the first abdominal segment; length 7-10 mm; wings unbanded, 
lightly tinged with brown. Female: maxillary palpi of moderate 
length ; mentum with a number of strong setae arising near base and 
directed forward, much as in Auplopus ; mandibles slender, with 
scattered, strong bristles (Fig. 5) ; labrum wholly concealed; clypeus 
not extending under lower margins of eyes; malar space about one 
third as long as width of mandibles at their base; temples well de- 
veloped, not strongly receding, nearly as wide as eyes; vertex ex- 
tended well above eye tops ; ocellar triangle located well before 
vertex crest; propodeum with smooth contours, slope low and even; 
legs relatively smooth, but middle and hind tibiae bearing numerous 
spines of moderate length ; claws dentate, tooth arising rather close 
to outer ray; apical tergite with a flat pygidial area which is devoid 
of setae but is minutely punctate and shagreened. Male (Fig. 10) : 
head remarkably enlarged, much wider than thorax, vertex far above 
eye tops and ocelli, temples much wider than eyes; malar space about 
half as long as width of mandibles at their base; antennae elongate, 
capable of reaching middle of abdomen; tarsal claws and spines of 
tibiae as in female; first abdominal segment much expanded from the 
base, but with no evidence of a lateral seam. Subgenital plate tongue- 
shaped, midline only weakly elevated (Fig. 8) ; genitalia with the 
basal hooklets absent, parameres elongate, digiti broad and abruptly 
truncate apically (Fig. 9). 
Remarks. — This genus is most closely related to Auplopus, dif- 
fering in the less strongly petiolate abdomen (especially in the male), 
the less well defined pygidial area, presence of a short malar space, 
broad clypeus with a slightly concave apical margin, and several 
other features. The male genitalia differ in no important details 
from those of Auplopus. 
