THE NATURAL HISTORY OF THE 
WORKERLESS ANT PARASITE 
FORMICA TALBOTAE 
By Mary Talbot 
The Lindenwood Colleges, 
St. Charles, Missouri 63301 U.S.A. 
Abstract: The ant Formica talbotae Wilson is a workerless social parasite of 
the microgyria group, which forms mixed colonies with the host ant Formica 
obscuripes Forel. Queens produce males and females only and there is also no 
worker brood of F. obscuripes in the parasitized colonies. The small alates have 
a long flight period stretching from mid-June to late September, with flights 
taking place on every suitable morning when the temperature is above 71° and 
rising, when the sun is shining, and when there is no appreciable wind. Flights 
are best between 78° and 83° F. Once up on plants, alates are reluctant to return 
to the nest so some flights, under poor conditions, are long drawn out. Flights 
are sparse, usually only 10 to 75 alates taking off in a day. Sometimes there is 
a small swarming reaction, with females loitering on plants above the nest while 
males fly about until they find them and mate. 
Formica talbotae Wilson is the only known workerless social 
parasite of the genus Formica (Wilson, 1977). The queens live 
in colonies of the thatching ant, Formica obscuripes Forel, and 
produce winged males and females all through the summer. Since 
all of the brood in such a colony is that of the parasite (a few F. 
obscuripes males may be produced and are probably the result 
of worker-laid eggs), it is assumed that the small fertilized fe- 
males enter colonies which lack queens or in some unknown man- 
ner bring about the death of any queen which may be present. 
E. O. Wilson (1977), who described F. talbotae , reports that 
this small member of the microgyria group has also been found 
at Spirit Lake, Iowa, by Robert L. King and near Grand Forks, 
North Dakota, by Paul B. Kannowski. 
The F. talbotae colonies presented here were associated with 
five colonies of F. obscuripes on the Edwin S. George Reserve, 
Livingston County, Michigan. This is near the eastern margin 
for the distribution of the host ant, which is essentially a prairie 
form. F. obscuripes finds an excellent habitat on the Reserve 
since there are open, sloping fields which are sandy and well 
drained. Mounds are numerous in some fields, a condition nec- 
essary for the existence of such a parasite as F. talbotae. 
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