28 o 
Psyche 
[September-December 
OBSERVATIONS ON L. VEGETA 
Females of this species are about the same size as those of L. 
chilopsidis (approximately 15 mm) but are much darker in color, 
almost black. Bohart and Bohart (1966) reported the species from 
the central Great Plains in Wyoming, Colorado, western Nebraska, 
northern Arizona, and the base of the Texas panhandle. Our ob- 
servations were made near Hasty, in southeastern Colorado, in early 
July 1975. 
The behavior of this species appears almost identical to that of 
L. chilopsidis. Although one female L. vegeta was followed by a 
satellite fly (not identified), the majority were not (Table 1). Only 
one interaction between wasp and prey was observed. At 1000 on 
5 July, a female was observed digging on the surface of a dune. 
She located a burrow and entered. We excavated the burrow about 
5 minutes later; as it had not been filled it was easy to trace to the 
cell. The burrow formed an angle of about 10 degrees with the 
flat sand surface. It was straight for 34 cm, where the wasp and 
paralyzed prey were found about 15 cm below the surface. The 
prey was an immature female sand treader camel cricket, Daihiniella 
sp. The wasp had not yet laid an egg on her prey. 
DISCUSSION 
Both Larropsis chilopsidis and L. vegeta females obtain their prey 
by searching the sand surface for sand treader camel cricket burrows. 
Apparently they use olfactory cues to locate active burrows. Sup- 
port for this hypothesis comes from an observation made after re- 
moving a cricket prey and egg of L. chilopsidis from the cell. A 
searching female walked into the hole we had dug out and showed 
much interest in the empty cell, digging in the area for several 
seconds. 
Very little is known about the biology of sand treader camel 
crickets. There are several genera in the group (Tinkham, 1942), 
all characterized by a “sand basket” of spurs on the upper distal 
end of the posterior tibiae. An Ammobaenetes phrixocnemoides kept 
in the laboratory was observed to remove sand from its burrow by 
moving backwards, pushing sand behind it with the aid of the sand 
baskets. These insects are nocturnal and dig a simple, oblique bur- 
row in which they pass the day (Tinkham, 1942). A searching 
female Larropsis is therefore more likely to find her prey deep in 
the burrow. 
Our observations suggest that both species normally find and 
sting their prey underground, where the cricket has little opportunity 
to escape. In observation A (L. chilopsidis) the wasp had evidently 
