COLEOPTERA OF BAJA CALIFORNIA. 433 



Lystronychus Championi n. sp. 



Entirely black, sub-opaque. Head densely and rela- 

 tively coarsely punctured. Thorax more than half wider 

 than long, sides strongly arcuate from the front angles to 

 middle where there are two distinct teeth, thence narrow- 

 ing to base, disc regularly convex, very densely punc- 

 tured. Elytra broader than the thorax, slightl}^ wider 

 behind the middle, disc with striae of very closely placed 

 punctures, the intervals flat with a single row of punc- 

 tures, some of which are much larger and bear a short, 

 erect, stiff black hair, submarginal stria quite deeply im- 

 pressed. Prosternum coarsely sparsely punctate, the 

 pleurae densely punctate. Meso-metasternum coarsely 

 punctate. Abdomen shining much more finel}' and 

 sparsely punctate. Legs black, punctate. Length, .28 

 inch ; 7 mm. 



A slightly larger and more convex species than scapu- 

 lar is with less opaque surface, which has a faint bluish 

 tinge. The humeral red spot in the Mexican species 

 being a constant character affords an additional means of 

 distinction. The above described species with scapularis 

 and dcnticoUis agree in having the sides of the thorax bi- 

 de ntate. 



I dedicate the species to Mr. Champion, who has given 

 us in his treatment of the genera of Mexico the correct 

 elements for proper classification of the family. 



One female, western Texas. 



The two species now known in our fauna are as follows : 



Antennae slender, outer joints not flatteneil; thorax scarcely witler than 

 long, the sides not dentate. jydiferus. 



Anteunse broader externally, the joints subserrate; thorax broader than 

 lono, sides bidentate at middle. Championi. 



Both species occur in Texas, the former extending as 

 far as Brazil. 



