THREE NEW CRETACEOUS ACULEATE WASPS 
(HYMENOPTERA) 
By Howard E. Evans 
Museum of Comparative Zoology 
Aculeate Hymenoptera have been known from the Mesozoic only 
from the Upper Cretaceous wasp Cretavus sibiricus (Sharov, 1957) 
and the ant Sphecomyrma freyi , known from two workers from the 
lower part of the Upper Cretaceous (Wilson, Carpenter, and Brown, 
1967). Wasps evidently quite similar to living forms are, however, 
known from the Green River shales, of Eocene age (Cockerell, 
1922), as are several ants, and a diversity of wasps, ants, and bees 
occur in Baltic Amber. Thus it has seemed probable that the 
Aculeata underwent a radiation in the Cretaceous, although the 
scarcity of fossil insects from this period has made it difficult to 
document this radiation. 
Quite recently three fossil wasps from Cretaceous deposits have 
come to my attention. These do indeed indicate that the Aculeata 
became quite diversified before the end of the Mesozoic. One of 
these wasps, which I have placed in the new genus Archisphex , has 
a generalized aculeate venation but is very probably a sphecid. Only 
one wing is preserved, but this is in good condition and is noteworthy 
as the first evidence of an aculeate to be found in Lower Cretaceous 
deposits. A second wasp, described in the new genus Lisponema , is 
an undoubted sphecid, having a specialized wing venation strikingly 
similar 'to that of the modern genus Spilomena ( Pemphredoninae) . 
It is known from a headless but otherwise well preserved specimen 
from Cedar Lake Amber (Manitoba, Canada). Another wasp in 
these same deposits is a bethyloid obviously related to the cuckoo 
wasps, which I have placed in the new genus Procleptes ; it is also 
quite well preserved although lacking most of the wings. 
Thus there is now evidence that three diverse stocks of aculeates 
(sphecids, bethyloids, and ants) were present in the Cretaceous. 
Cretavus is usually assumed to be a scolioid (although there are 
certain unusual features of the wing), and eumenid wasps are known 
from the Eocene (Evans, 1966, p. 394). Thus we may say that 
representatives of three superfamilies were certainly present in the 
Cretaceous, two others almost certainly. These include the ancestral 
stocks of all the social forms, since the vespids were surely derived 
from eumenid stock, the bees from a primitive sphecid perhaps not 
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