A STUDY OF THE PHYLOGENY OF THE 
ANTEONINAE " 
F: A. FENTON 
A study of the biology of insect parasites and their relationships 
with that of their hosts offers a most attractive and productive 
field for research^ and as yet, comparatively speaking, but little 
has been done in this field. This is particularly true with the 
Hymenoptera, and the writer has been interested in working out 
the biology of the Anteoninae, one of the parasitic groups of this 
order. These insects are parasitic on three families of the 
Homoptera, namely, the Cicadellidae, and Fulgoridae, commonly 
known as leafhoppers, and the Membracidae or treehoppers. 
With the possible exception of members of the most primitive 
genus, the larvae of the Anteoninae in their later stages are all 
attached externally to the host, protected and encased in the 
larval exuviae, which instead of being cast off as is the case with 
other insect larv«, are retained as a sort of sac for protection. 
Furthermore, with the exception of the genus Aphelopus, all the 
females have the front pair of legs greatly lengthened and other- 
wise adapted for grasping purposes. The coxa is excessively 
elongated, being often more than half as long as the femur ; the 
trochanter is long and often somewhat curved; the femur is 
strongly club-shaped and the tibia is thicker and shorter than the 
others. The greatest and most striking change has taken place in 
the fore tarsi, however, these being modified to form a chela or 
grasping organ 'fitted for holding the active prey, a character 
not found in any other insect group (Fig. 56. 7). The chela is 
composed of two arms or “pincers,” one being the fifth tarsal 
joint which is proximally more or less lengthened, and the other 
one of the tarsal claws which has become greatly elongated. 
The remaining claw is much reduced or normal and is enveloped 
by the lobes of the empodium. These chelae show a great range of 
variation and complexity within the group, being variously pro- 
vided with spines and lamellae (Fig. 56). In addition to this 
structure, which is peculiar only to thq females, this sex has 
1 This group has been variously given the rank of family (Dryinidae) and sub- 
family (Anteoninae) by different writers. It is also included by some in the super- 
family Proctoturpoidea, and by others in the Vespoidea. 
