242 NEOTROPICAL PSELAPHIDAE 



Intermediate legs not armed as described rugosus Female 



5. Intermediate and posterior tibiae mucronate or spined at apex; ver- 



texal foveae small and obscure; supraocular carina indistinct; lateral 



pronotal spines relatively large and triangular; 2.25 mm 



hamaticollis Male 



Intermediate and posterior tibiae not mucronate or spined at apex, the 

 apex simply pubescent; vertexal foveae deep, large and distinct; 

 supraocular carina strong and distinct; lateral pronotal spines small; 

 1.7 mm 6 



6. Antennal segments VIII, IX, and X abnormally produced on the ven- 



tral face ; metasternum with a large, erect spine at middle of apical 

 margin ; intermediate femur with a lamellate spine at basal third and 

 a sharp conical spine at center of ventral face; intermediate tibia 



contorted and with a large tooth at apical three-fourths 



sternadens Male, new species 



Antennae, metasternum and intermediate legs simple 



sternadens Female, new species 



7. Pronotum rugose and granular; 2.7 mm anthicoides Female 



Pronotum varying from shining and lightly punctulate to slightly 



granular 8 



8. Antennal segments VIII, IX, and X progressively transverse; 2 mm. 



rivularis Female 



Antennal segments VIII and IX either much longer than wide or 

 quadrate 9 



9. Lateral pronotal fovea large, elongate, nearly sulciform ; vertex tumid, 



with sharply defined fovea and sulci; 2.5-2.7 mm 10 



Lateral pronotal fovea small, circular, never sulciform; vertex flat- 

 tened, with punctiform vertexal foveae and obsolete sulci 11 



10. Intermediate femur with a small spine at base; intermediate tibia with 



a strong triangular tooth beyond middle on ventro-posterior face. . 



bispinosus Male 



Intermediate legs not as described bispinosus Female 



11. Head much longer than wide 12 



Head either quadrate or much wider than long 13 



12. Intermediate trochanters with a very long, biarcuate spine 



armatus Male 2.4. mm. 



Intermediate trochanters not armed armatus Female 2.6.mm. 



13. Pubescence fine in quality and very short; vertexal sulci almost in- 



visible ; 2 mm simplex Female 



Pubescence long and coarse; vertexal sulci relatively developed; 2.8 

 mm forticornis Female 



Oxarthrius sternadens new species 



Holotype Male. Measurements: head 0.268 x 0.435 through eyes; cervicum 

 0.033 mm. ; pronotum 0.4 x 0.4 mm. ; elytra 0.53 x 0.67 mm. ; abdomen from a 



