160 NEOTROPICAL PSELAPHIDAE 



Male with segments of antennae III, IV, and VI two times longer than 

 wide ; V and VII three times longer than wide ; VIII one-half longer 

 than wide ; IX slightly longer than eighth ; X two times longer than 

 ninth; XI fusiform, slightly sinuate, truncate at base; middle legs 

 with trochanters more strongly lunate and mesially toothed ; middle 

 femora gibbous but not ventrally toothed at middle ; middle tibiae 

 slightly notched apically but not having the large, recurved spine 

 at apex. 2.6 mm. Female unknown crassipes 



crassipes Raffray. 1904. Bolivia. 



hamata Raffray. 1904. Bolivia. Genotype. 



XYBARIDA (Raffray, 1896) 

 Raffray (1896, 1904, 1908) 



This small brachyglutine genus of only four species is widely distributed 

 from southern Brazil, the Panama Canal Zone, into Yucatan. The species 

 agree in having a short, globiform body and one species at least may be a 

 facultative synoekete of a species of termite. The genus is structurally related 

 to Scalenarthrus, Xybaris and their allies. The four known species may be 

 isolated by the following key: 



Antennal segment IX wider than long 2 



Antennal segment IX longer than wide nasicola new species 



2, Pronotum with a very minute, punctiform, median fovea at base. ... 3 

 Pronotum with no median pronotal fovea punctulum 



3. Known only from southern Brazil clavata 



Known only from Yucatan pusilla 



Xybarida nasicola new species 



Holotype Male. Measurements: head 0.23 x 0.30 mm.; antennae 0.67 

 mm.; pronotum 0.30 x 0.35 mm.; elytra 0.53 x 0.53 mm.; abdomen 0.33 x 0.50 

 mm.; total length 1.4 mm.; greatest width 0.53 mm. (PI. VII) 



Body subglobular, light reddish-brown, moderately shining, and punctulate 

 with vertex and occiput more strongly punctate; pubescence short (0.02 mm. 

 long), sparse, golden. Eyes prominent, consisting of about 34 small facets 

 each, and 0.067 mm. long. Tempora one-half longer than eye, and convergent 

 to subtruncate occiput. Occiput, vertex, and epistome punctate and pubescent, 

 semi-shining and in strong contrast to the glabrous, shining cervicum. Vertex 

 convex between the vertexal foveae, which are small, about equal to an eye 

 facet in diameter, and nearer the eyes than to each other. No circumambient 

 interocular sulcus, but front between the antennal bases, and behind the 

 rounded frontal margin, broadly, shallowly concave. Front simple, gradually 

 declivous to epistome. Epistome elongate, roughly punctate and with longer 

 pubescence, its apical margin strongly rounded and convex. Labrum prominent 

 as a semilunar, subdetached plate. Mandibles conspicuous, left crossed over 



