DYNASTIN/E 129 



Body elongate, very moderately convex, strongly shining, glabrous, 

 flavate, piceous beneath, the head and pronotum black, the latter 

 pale at the sides and sometimes along the base medially, extending 

 thence faintly along the medianline for some distance; clypeus rufous; 

 elytra with the suture, finely margining the scutellum, a humeral and 

 post-medial, more internal, dash, and part of the lateral swelling 

 of the female, black; pygidium blackish, the legs and tarsi rather 

 pale in color; head three-fifths as wide as the prothorax, shining, 

 rather strongly and closely punctate from the suture, the punctures 

 becoming gradually very fine and sparse basally; clypeus flat, as 

 long as all the posterior part, trapezoidal, with arcuate sides, not 

 quite twice as wide as long, the angles much rounded into the 

 rounded apical lobes; margins fine and slightly elevated, thickened 

 around each of the lobes; surface with well spaced and very irregular, 

 transversely interlacing rugulae, the suture fine but distinct, entire, 

 sinuate medially; antennal club barely more than twice as long as 

 thick; eyes moderate but rather strongly convex; prothorax scarcely 

 one-half wider than long, the sides parallel and very evenly rounded, 

 gradually a little more converging anteriorly to the acute and very 

 sharply pointed angles, the basal very broadly rounded; base broadly 

 arcuate, not definitely lobed, having a fine entire bead, which is 

 also very fine along the lateral margins but wider and flat at apex; 

 surface with fine, sparse but distinct punctures, still stronger and 

 less sparse laterally; there is a small punctureless discal area at each 

 side of the middle anteriorly; scutellum pale, fully as long as wide, 

 unusually acutely triangular; elytra nearly a third longer than wide, 

 at the swelling at three-fifths a fourth or fifth wider than the 

 prothorax, circularly rounded at apex, having small, shallow and not 

 very sparse confused punctures, with two or three geminate series 

 more or less distinct on each; humeral swelling in the form of a long 

 ridge, which also reappears toward apex; below the humeral ridge a 

 more slender ridge begins and terminates, becoming larger, at the 

 end of the lateral swelling ( 9 ) ; edge below this ridge serrate and with 

 short spiniform setae; pygidium rather convex, shining, finely, rather 

 closely, shallowly and very irregularly punctulate throughout, 

 slightly tumid at the narrowly rounded apex; abdomen impunctate, 

 excepting the single loose transverse line of setigerous punctures on 

 each segment, extending across the middle; legs slender, the tarsi 

 long and filiform; hind tibiae much shorter than the femora. Length 

 (9 ) 12.8-13.0 mm.; width 6.2 mm. Isthmus of Panama (Culebra), 

 Gaillard. Two examples *discicollis Arrow 



The relatively rather large head in this species might seem to 

 indicate a relationship with Mononidia and Stigmalia, but its affini- 

 ties are otherwise so clearly with Ancognatha, because of the exca- 

 vated ligula, and with Cyclocephala, because of the general habitus 

 and ornamentation of the body, finely margined pronotal base 

 and other characters, that there can be scarcely any doubt of the 

 T. L. Casey, Mem. Col. VI, Oct. 1915. 



