402 bulletin: museum of comparative zoology. 



Worker. Length 6-9 mm. 



Body robust; head, exchiding the mandibles, about as broad as 

 long, narrowed in front, with rather straight sides and feebly and 

 broadly excised posterior border. Mandibles broad. Clypeus with 

 a distinct notch in the middle of its anterior border. Pro- and meso- 

 notum in profile slightly depressed; mesoepinotal impression rather 

 deep and angular; base and declivity of epinotum forming together 

 a rounded angle. Petiole broad, with a sharp border, which is either 

 entire or with a median emargination. 



Body subopaque; head slightly lustrous; mandibles finely striato- 

 punctate. Frontal area not shining. 



Hairs whitish, sparse, suberect, present on the dorsal surface of the 

 head, pronotum, fore coxae, and gaster, absent on the border of the 

 petiole; short on the upper surface of the gaster, longer and more 

 abundant on the venter. Legs without hairs, except the row of oblique 

 bristles along the flexor surface of the tibiae and metatarsi. Pubes- 

 cence very fine and sparse on the head and thorax, longer, dense, and 

 grayish on the gaster. 



Head, thorax, petiole, legs, and antennae light or dark red; front 

 and vertex more or less infuscated. Gaster black, with the anus and 

 usually a spot at the base of the first segment, red. 



Female. Length 9-11 mm. 



Color darker and more brownish than that of the worker; head 

 above and behind black; mandibles, clypeus, cheeks, and antennae 

 brown; mesonotum with an anteromedian, and a pair of parapsidal 

 blotches of the same color. Wings brownish, darker towards the base. 

 Pilosity and pubescence as in the worker. 



Male. Length 7-10 mm. 



Mandibles broad, with 4-5 teeth. Clypeus convex, carinate, with a 

 sinuous emargination in the middle of its anterior border. Head, 

 excluding the mandibles, a little broader than long, with straight 

 posterior border and rounded posterior angles, much narrower in the 

 region of the cheeks, which are shorter than half the eyes and feebly 

 concave. Petiole broad and thick below, with thin, sharp superior 

 border, broadly and rather deeply excised in the middle. 



Surface of head and thorax opaque, densely shagreened; gaster 

 somewhat glossy. 



Hairs short and sparse; pubescence fine, rather uniform on the 

 head, thorax, and gaster, but not dense enough to conceal the surface. 



Black; legs yellow; antennae brown or blackish; scapes sometimes 

 paler; genitalia brownish or reddish yellow. Wings colored like those 

 of the female. 



Hosts (Slaves) : F. fusca; F. fusca var. glebaria, F. fusca gagates, 

 F. nifiharhis, and F. cincrca. 



