18 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 120 
Through the courtesy of Dr. K. C. Emerson, BMNH specimens 
from the type host, here examined, were determined to be conspecific 
with the USNM holotype and allotype (USNM 40137, Nytonga, 
Congo, Africa, Nov. 3, 1917, collected by E. A. Chapin). 
Male: As illustrated in figure 24. Larger than other species of 
the lophocerus species-group in all measurements except width of 
abdomen; approximately the same size as Chapinia traylori (table 1). 
Venter of third femora and posterolateral margins of abdominal 
sternites IV-VI each with small scattered brushes of normal setae. 
Each lateral margin of abdominal tergites II-VI without a short 
seta between the spiracle and postspiracular seta. Abdominal 
sternite II with 48-66 total setae and one median row of setae on 
posterior margin. Terminal abdominal segments as shown in figure 
24c. Genitalia as shown in figure 7, each lateral horn with one large 
sharp point which crosses the broad endomeres. 
Female: As illustrated in figure 23. Larger than Chapinia camuri 
in all measurements except length of head; approximately the same 
size as other species of the lophocerus species-group; slightly smaller 
than C. traylori in all measurements except length of head (table 2). 
Resembles the male except that abdominal sternite II has 56-68 total 
setae. ‘Terminal abdominal tergite with 20-24 setae, short setae 
alternating with long, on posterior margin; ventral sclerite between 
vulva and anus elevated medially between sclerital hooks (fig. 31). 
Anal fringe with 56-62 setae (fig. 32). 
Discussion: Ewing (1927) gave the following measurements (in mm). 
male female 
width of abdomen 0.70 0.95 
total length 1.59 2.00 
These measurements are not as great as those given here for Chapinia 
robusta (tables 1, 2). C. robusta resembles most closely C. bucerotis. 
The venter of the third femora and posterolateral margins of abdom- 
inal sternites IV-VI each have small scattered brushes of normal 
setae in C. robusta, slightly more numerous than for other species of 
the lophocerus species-group, except C. bucerotis, which has large thick 
brushes of normal setae. Each lateral margin of abdominal tergites 
II-VI in C. robusta lacks the short seta between the spiracle and 
postspiracular seta that is present in all other species of the lophocerus 
species-group. Abdominal sternite II has one median row of setae in 
C. robusta but three median rows of setae in C. bucerotis. Male geni- 
talia have each lateral horn possessing one sharp median point that 
crosses the broad endomeres in C. robusta but two sharp posterior 
points, one of which crosses the broad endomeres, in C. bucerotis. 
The ventral sclerite between female vulva and anus is elevated 
