no. 3616 GENUS EUPARIXIA — WOODRUFF AND CARTWRIGHT 15 



Sternum : The inesosternum is similar to E. duncani and E. bruneri 

 but the depressed, median, very finely alutaceous area is sharply 

 outlined and obovate in shape, the edge of the anterior half of this 

 area, as well as the edge of the flattened diverging borders, irregularly 

 cut into by the close, deep, coarse, longitudinally elongate punctures 

 that cover all the anterior part of mesosternum. Metasternum as 

 in E. duncani but disc covered with rather close, shallow, moderate 

 punctures and alutaceous sculp ture; a few coarse, close punctures 

 between mesocoxae and the arcuate anterior border of the depressed 

 area in front of the posterior coxae; lateral area between mesocoxae 

 and sides strongly bordered by groove of coarse punctures, otherwise 

 a very few punctures and scattered small tubercles. 



Abdomen: Each abdominal sternite depressed on anterior one-half, 

 this depression with longitudinal ridges irregularly spaced. The 

 posterior one-half of each sternite coarsely, irregularly punctate. 

 Metasternum with median sulcus moderately impressed, covering 

 entire length; entirely punctate as in the femur (including depression 

 where femur rests). Pygidium nearly concealed, a transverse de- 

 pression paralleling the apical border and a longitudinal depression 

 in middle reaching to transverse depression. 



Legs: Anterior tibiae tridentate; apical tooth broad, bent outward 

 at nearly right angle to tibia. Apical spur elongate, narrow, slightly 

 longer than combined length of first three tarsal segments. Anterior 

 trochanter large, prominent, impunctate, rugose ventrally. Anterior 

 femoral groove and about one-half the dorsal surface of femur covered 

 with fine, short, golden setae. Posterior femur with marginal groove 

 covering one-half the length from the apex. Terminal spurs of middle 

 and posterior tibiae unequal: the longer spur four-fifths the length 

 of the first tarsal segment; shorter spur two-thirds the length of the 

 longer one. Middle and posterior tibiae nearly straight, narrow, 

 slightly curving outward toward the weakly expanded apex. First 

 segment of middle and posterior tarsi equal in length to next three 

 segments combined. 



Diagnosis: Small for the genus and darker than usual. Differs 

 from all known species in pronotal outline (fig. 4). The explanate 

 margin is narrower than E. duncani, E. bruneri, or E. moseri. It 

 differs from E. bruneri and E. moseri in having the metasternum 

 punctate. It differs further from E. duncani in the rounded angle 

 at the constriction rather than an acute one. It also differs from all 

 others in distribution and host ant species. 



Host: Recorded by Hinton (1934) as being found with Atta sexdens 

 at the type-locality, but that species is not now known from Mexico 

 and this record probably refers to Atta mexicana. Although this 



