THE HABITAT OF H3NIGMATIAS (DIPTERA: 
PHORIDyE) 
By C. T. Beues 
Biological Laboratories, Harvard University 
The sexes of tlie interesting genus 2Eni g matias like those 
of many Phoridae are extremely dissimilar owing to the 
apterous condition and otherwise profoundly modified 
and degenerate form of the female. Three species, 
known from the winged male have been found in North 
America. The female of one of these is known, defi- 
nitely associated with the male from a pair taken in 
copula by Mallocli and described by him as JEnigmatias 
flavofemorata. Mallocli ’s types were from Illinois, col- 
lected “on a sandy bank along the Illinois Central Rail- 
road between White Heath and the Sangamon River.” 
As the genus is known definitely to be myrmecophilous, 
at least in Europe, the specimens taken by Mallocli were 
quite probably from the nest of some ant in the vicinity. 
Previous to this a single female was taken in Arizona 
by Coquillett and described by him as 2E. schwarzii. 
Of this he says ‘ 4 it occurred on low vegetation in a local- 
ity where no ant nests could be found.” 
During the summer of 1945, the present writer col- 
lected a large number of miscellaneous insects on sheets 
of “tanglefoot” fly-paper in northwestern Massachusetts 
while making a census of insects to determine the effect 
of DDT on the insect fauna of woodlands. Among the 
more than 300,000 specimens obtained (of which some 
51% were Phoridae) was a single female of JEnig matias 
from Petersham, August 4. This, which is apparently 
the third female to be reported from North America, was 
trapped on the trunk of a tree several feet above the 
ground. From this, and from the experience of both 
Coquillett and Mallocli it is apparent that these tiny 
wingless JEnigmatias wander freely from the ant nests 
where they are domiciled, perhaps following foraging 
ants. This specimen is not sufficiently well preserved 
to determine whether it is 2E. -flavofemorata , or more 
probably, JE. eurynota Brues known from a male col- 
lected in 1910 by Mrs. Brues at Forest Hills, Massachu- 
setts. 
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