1978] 
Burnham — Social Insects in Fossil Record 
99 
Cretaceous 
The Cretaceous Period has, without question, provided more 
information on the early evolution of the ants than any other 
period, primarily because of the discovery in 1967 of two perfectly 
preserved worker ants in a New Jersey amber deposit. No doubt 
exists as to the primitive nature of these Cretaceous ants — both are 
members of the same species, Sphecomyrma freyi Wilson and 
Brown, and possess a mixture of wasp and ant characters. The 
petiole is distinctly ant-like, although the mandibles, which are short 
and bidentate, are very wasp-like (see Fig. 3A). A new subfamily, 
Sphecomyrminae, was named to accommodate S. freyi (Wilson, 
Carpenter, and Brown, 1967), and is considered ancestral to all 
known formicid subfamilies (see Taylor, 1978). 
Since the discovery of Sphecomyrma, several other Cretaceous 
ants have been found, and these provide strong evidence that the 
family was widespread during this period. Dlussky (1975) described 
two new genera and three species, Cretomyrma arnoldii, C. uni- 
cornis, and Paleomyrmex zherichini (from a Late Cretaceous amber 
deposit in Yantardak, USSR) which he assigned to the Sphecomyr- 
minae. It is of interest that the type of P. zherichini is the first 
winged male ant to be found in a Cretaceous deposit and provides 
the only indication of wing venation in the Sphecomyrminae (Fig. 
3B). The figured specimen of Cretomyrma unicornis raises doubts 
as to its position in the Formicidae for it is a badly mangled, poorly 
preserved specimen and might be better assigned to Hymenoptera 
incertae sedis. 5 A fifth specimen, apparently a worker, has recently 
been discovered in the Cretaceous amber of Manitoba, Canada. 
Although not yet described, it undoubtedly belongs to the subfamily 
Sphecomyrminae (Wilson, personal communication). 
Paleocene 
No ants from the Paleocene are known, undoubtedly because so 
few fossiliferous beds containing insect remains from this epoch 
5 Dlussky (1975) also described several other “ants” which were found in Upper 
Cretaceous deposits in the Kzyl-Zhar of Russia. Three genera (3 species) were placed 
in the subfamily Ponerinae: Petropone petiolata, Cretopone magna, and Archaeo- 
pone kzylzharica. These are all fragmentary specimens, and, as figured by Dlussky, 
present no characters which would place them unequivocally in the Formicidae. They 
much more obviously belong in Hymenoptera incertae sedis, as does Dolichomyrma 
longiceps from the Upper Cretaceous of Kzyl-Zhar, which Dlussky put into 
Formicidae incertae sedis. 
