1967] 
Brown Kempf — Tatuidris 
185 
Male unknown. 
The tribe Agroecomyrmecini occupies a basal position in subfamily 
Myrmicinae, and in fact it may well represent the relicts of the 
primitive stock connecting the Myrmicinae to the ancestral tribe 
Ectatommini in subfamily Ponerinae, as already proposed by Brown 
( I 954)- Like Myrmica and allies among the lower Myrmicinae, 
the Agroecomyrmecini have pectinate spurs on the last two pairs of 
tibiae, but they are more primitive than Myrmica in the structure 
of the petiole, postpetiole and gaster. These characters recall the 
ectatommine genera Gnamptogenys and Proceratium , and the sculp- 
ture of Agroecomyrmex and Eulithomyrmex also matches that of 
various Gnamptogenys species-groups. The new genus Tatuidris is 
more specialized in its almost complete loss of sculpture, as it is also 
in other obvious ways. 
The new genus affords one case in a small but growing list of 
insect taxa found alive only after their other representatives had 
already been described as fossils. The Agroecomyrmecini are evi- 
