1975 ] Buren , Nickerson and Thompson — Conomyrma 
313 
mapped and the distribution of the 3 types of nests determined as 
shown in Fig. 1. Although the ratio of C. insana to C. flavopecta 
workers in the original mixed nest was about 7 to 3, the ratios of 
C. insana to C. flavopecta in the mixed nests observed at the time of 
mapping was about 20 to 1, judging from the workers appearing at 
the nest entrances (no further nests were excavated, however). The 
area was mapped again on 26 June (Fig. 2). Although the unmixed 
C. flavopecta population appears stable, obvious changes occurred in 
the C. insana population. The numbers of individual nests in the 
unmixed C. insana enclaves increased, there was a new enclave of 
unmixed C. insana in the area formerly occupied by the mixed nests, 
and only 1 mixed nest could still be found, this one with an esti- 
mated 100 to 1 insana to flavopecta ratio. 
The speed of the change over from the mixed nests to the new 
unmixed C. insana enclave was surprising to us and we have no 
unequivocal explanation for this phenomenon. Although we observed 
no overt actions of the C. insana workers against C. flavopecta in 
the mixed nests, the death rate or attrition of the latter may be 
greater than normal for reasons we do not understand. We also 
have no certain explanation for the clustering of the mixed nests in 
one small part of the study area. Perhaps the process of hesmosis 
begins to occur even while the nests are still mixed. Obviously one 
or more additional C. insana queens were present in these mixed 
nests, because the new C. insana enclave proceeded in its develop- 
ment even after the C. insana queen found in the original nest was 
removed. 
This is the first report of temporary social parasitism in the genus 
Conomyrma. It may be noted that mixed nests of Conomyrma have 
been recorded (as Dorymyrmex) previously by Wheeler (1901) 
who gave the remarks of Forel upon finding mixed nests of ants 
identified as Dorymyrmex pyramicus var. niger Pergande and D. 
pyramicus var. flavus McCook near Faisons, North Carolina. Forel 
attributed these mixed nests to a queen of each taxon fortuitously 
associating together when first founding a new colony. Such a chance 
association of 2 species of females has never been confirmed for any 
ants as far as we are aware, although reported in older literature 
(Forel 1874, Wheeler 1901). In the Forel colonies all alates found 
were identified as niger except for 1 male which Forel identified as 
flavus on the basis of color. In the absence of any positive state- 
ment, we assume no dealate queens were found to confirm Forel’s 
hypothesis. 
