236 
Psyche 
[December 
I have described another group of wasps also having 13-segmented 
antennae in the female and sharing some features with the Scolioidea 
and some with the Bethyloidea. This is the family Scolebythidae 
(Evans, 1963), known from one genus and species in Madagascar 
and one genus and species in Brazil. Female scolebythids are winged 
and apparently adapted as parasites of wood-boring insects. I de- 
scribed the family without knowledge of the male, after considering 
and rejecting the possibility that Plumarius might represent the 
male sex of scolebythids. This was a fortunate decision, since I have 
not only discovered the female Plumarius but also a male of the 
scolebythid Clystopsenella longiventris Kieffer. This male was with 
a series of females of this species collected by Fritz Plaumann on 
October 5, 1952, at Rondon, Parana, Brazil. There is virtually no 
sexual dimorphism in this species, except that the male metasoma 
is simple, lacking the modification of sternite V of the female, and 
the terminalia are of course different (though the slide mount I 
made of the terminalia was lost before I studied it in detail, and 
I am therefore still unable to present any notes on the terminal 
structures of the male). Other minor differences from the female 
are as follows: antennae considerably more slender, though otherwise 
similar; vertex considerably less produced above the eye tops; front 
femora less robust. The structure of the mesosoma is especially sim- 
ilar in the two sexes, including all details of the wings. 
There is no question, then, that the Scolebythidae and Plumariidae 
represent two very different families, now both known from both 
sexes. In the former there is little sexual dimorphism, and one as- 
sumes that both sexes are associated with burrows in wood in which 
their hosts live. In the Plumariidae there is marked sexual dimor- 
phism, the females presumably searching for their hosts beneath the 
ground in deserts, the males Hying about at night. Both families 
retain certain generalized features which suggest that they arose 
from a very primitive aculeate near the common ancestor of the 
Scolioidea and Bethyloidea: of special note are the 13-segmented 
antennae in both sexes, the fairly well defined proepimeron, and the 
lack of a constriction between the first two metasomal segments. The 
many striking differences are in large part associated with the very 
different habitats these wasps are believed to occupy. Probably the 
two families have evolved independently of each other and of other 
Aculeata since before the beginning of the Tertiary. A cladist would 
doubtless argue that both deserve superfamilial status. A realist 
might at the same time point to this as still another indication of the 
difficulties of grouping the Aculeata into superfamilies. As a realist, 
