402 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
WorkKER. Length 6-9 mm. 
Body robust; head, excluding 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; mesoépinotal 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. 
FreMaLe. 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. 
Mate. 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 (Staves): F. fusca; F. fusca var. glebaria, F. fusca gagates, 
F. rufibarbis, and F. cinerea. 
