NO. 3616 



GENUS EUPARIXIA — WOODRUFF AND CARTWRIGHT 7 



parixia agrees with Cartwrightia in the explanate pronotal margin, 

 basally constricted pronotum, epipleurae covering the tips of the 

 widely separated middle coxae, and the mesosternum extending 

 laterally more or less over part of the anterior half of the mesocoxae. 

 In Cartwrightia, however, the clypeus is not inflexed at the apex, 

 the margins and surface of the pronotum are very different, and only 

 alternate elytral intervals are carinate. Apically the elytra of 

 Cartwrightia are very much as in Ryparus. Cartwrightia seems to 

 be intermediate between Euparixia and Ryparus, combining characters 

 from each. 



In the explanate pronotal sides Euparixia is similar to Euparia 

 but Euparia lacks the inflexed clypeal apex, the basally constricted 

 pronotum, and cariniform elytral intervals; and in Euparia the 

 epipleurae do not cover the anterior tips of mesocoxae; the meso- 

 sternum is normally narrow between the coxae and does not extend 

 laterally over the coxae. 



Key to Species of Genus Euparixia Brown 



1 Elytral intervals moderately convex, not cariniform; pronotal outline 



as in figure 7; Costa Rica costaricensis Hinton 



1' Elytral intervals cariniform as in figure 5; pronotal outline not as above; 

 southern Mexico to Louisiana, including Cuba 2 



2 (1') Pronotum constricted only in posterior one-third, the posterior angles 



prominent and acute (fig. 2) ; Arizona and N. Mexico . duncani Brown 



2' (2) Pronotum constricted in posterior one-half or more, the posterior angles 



evident but rounded (figs. 3-5) ; distribution not as above .... 3 



3 (2') Lateral pronotal margin less explanate, outline as in figure 4, the posterior 



angles evident; central Mexico formica Hinton 



3' (3) Lateral pronotal margin broadly explanate, outline as in figures 3 and 5, 

 the posterior angles obscured, nearly obliterated; Cuba and Loui- 

 siana 4 



4 (3') Angle of the pronotal constriction more acute (fig. 3); Cuba; host: 



Atta insularis bruneri Chapin 



4' (4) Angle of the pronotal constriction less acute (fig. 5); Louisiana; host: 

 Atta texana moseri Woodruff and Cartwright 



Euparixia moseri Woodruff and Cartwright, new species 3 



Figure 5 



Holotype: Length 4.8 mm, width 2.2 mm. Elongate, convex, 

 feebly shining, reddish brown, basal margin of pronotum and legs 

 darker. 



Head: Clypeus widely truncate between weak angles, distance 

 between angles greater than length of the feebly arcuate side from 



3 This remarkable species is named in honor of Dr. John C. Moser, who is the 

 only person to collect the species and who has discovered many interesting myr- 

 mecophiles in his fine work on the biology and ecology of Atta texana in Louisiana. 



