NESTING BEHAVIOR AND DESCRIPTION OF THE 
LARVA OF BOTHYNOSTETHUS DISTINCTUS FOX 
(HYMENOPTERA: SPHECIDAE) 
By Frank E. Kurczewski 1 and Howard E. Evans 2 
Bothy nostethus is a predominantly neotropical genus having a 
single described species, distinctus Fox, in America north of Mexico. 
The genus has been little studied, and its placement in the sphecid 
classification has been the subject of some dispute. Kohl (1896) and 
Handlirsch (1925) put Bothynostethus in the Nyssoninae and related 
it to Alysson. In the Synoptic Catalog of Hymenoptera of America 
North of Mexico, Krombein (1951) placed it in the tribe Misco- 
phini of the subfamily Larrinae. More recently, Menke (1968) 
grouped Bothynostethus Scapheutes, W illinkiella, and Bohartella in 
the tribe Bothynostethini of the subfamily Larrinae. However, Evans 
(1964) has questioned, on the basis of larval structure, whether 
the Larrinae and Crabroninae deserve the status of separate sub- 
families, and he has cited Bothynostethus as a genus in which the 
adults resemble certain Crabroninae. Despite Menke’s (1968) in- 
clusion of the Bothynostethini in the Larrinae, he informs us 
(correspondence) that Bothynostethus is not a “typical” member 
of the subfamily, and that “it would not be difficult to derive a 
crabronid from a Bothy nostethusAAke. ancestor”. 
It is clearly of interest to discover what light a study of nesting 
behavior and larval structure may shed on these problems. Cazier 
and Mortenson (1965) found B. distinctus nesting in the ground 
and preying upon a chrysomelid beetle, but otherwise the genus has 
not been studied in the field. Recently we discovered a small aggrega- 
tion of B. distinctus nesting near Albany, N. Y., and a single indi- 
vidual nesting in Bedford, Mass., and we are able to present 
considerable new information on nesting behavior as well as a 
description of the mature larva. Our studies represent the first 
records of the species from those two states, as it has not previously 
been reported from north of New Jersey. In the Discussion we 
reconsider the proper phylogenetic placement of Bothynostethus. 
The specimens from our studies bear our note numbers and have 
department of Forest Entomology, State University College of Forestry, 
Syracuse, New York 13210. 
2 Museum of Comparative Zoology, Harvard University, Cambridge, 
Massachusetts 02138. 
Manuscript received by the editor July 5, 1972. 
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