1967] 
Brown & Ke?npf — Tatuidris 
189 
surface of head, front and sides of alitrunk, propodeal declivity and 
sides of nodes. Legs predominantly smooth and shining, with fine, 
rather long reclinate pilosity. 
Color yellowish ferruginous, thick margins, etc. often appearing 
more brownish or blackish. 
The single paratype worker is virtually identical with the holotype, 
but is a trifle larger (Head L 0.83, Head W 0.99, Weber’s L of 
alitrunk 0.80 mm). 
Holotype in Los Angeles County Museum of Natural History, 
Los Angeles, California; paratype in Museum of Comparative Zool- 
ogy, Harvard University, Cambridge, Massachusetts. Collected to- 
gether 2 miles south of Quetzaltepec (Quezaltepeque) , Prov. La 
Libertad, El Salvador, 17 July 1961, M. E. Irwin leg. The collec- 
tion was made by Berlese funnel from humus, and the sample also 
contained specimens of a small Solenopsis , an undescribed species 
of Eurhopalothrix , and O ctostruma balzani. Known only from the 
type collection. 
The generic name comes from Tatu, the Tupi word and also the 
modern Brazilian word for the armadilloes, plus the Greek-based 
idris. Tatusia is another old generic name for an armadillo. 
Though superficially Tatuidris bears some resemblance to species of 
the dacetine Glamyromyrmex complex of genera and to Phalacromyr- 
mex fugax , it can be separated at once by means of its 7-segmented 
antennae, its brush-bearing mandibles, its toothless propodeum, the 
form and proportions of postpetiole and gaster, and by the presence 
of pectinate spurs on middle and hind tibiae, among other char- 
acters. It is very strongly isolated among living ant genera, though 
clearly a myrmicine. From the fossil genera of the same tribe, 
Agroecornyrmex and EulithomyrmeXj Tatuidris is readily distin- 
guished by the shape of the head, 7-segmented antennae, lack of 
propodeal teeth, reduced sculpture, and also by the form and prob- 
ably the armament of the mandibles. 
It would be extremely interesting to know the food of Tatuidris ; 
the mandibular brushes and powerful sting together suggest that the 
ant specializes in catching some active or slippery live arthropod 
prey in the soil or soil cover. 
We acknowledge with thanks the aid of Mr. Roy R. Snelling who 
sent the specimens originally and generously allowed us to study 
and describe them. We are grateful also to the National Science 
Foundation for aid. The drawings are mainly the work of Mrs. 
