NORTH AMERICAN GEOTRUPINAE — ^HOWDEN 171 



Bolbocerosonia confusum Brown 



Bolbocerosoma confusum Brown, 1928, p. 194, Type, male, Oklahoma (CC), 



Length 10 to 12 mm., greatest width 7 to 8.5 mm. 



Dorsum reddish brown, marlied with black as follows in male: 

 Vertex and at least part of the clypeus, eyes, eye canthi, apical 

 pronotal margin between lateral carinae, all of pronotal declivity 

 except at midline, lateral limiting grooves, band on pronotal base not 

 extending forward at midline and extending laterally no farther than 

 elytral margin, scutellum, sutural intervals, extrem.e base of elytron, 

 usually apical half of elytral margin, and an oval spot. Oval spot 

 slightly postmedian, parallel to the striae, extending from fourth to 

 eighth elytral striae, almost twice as long as wide (figured by Brown) . 

 Spot is not confluent with any other black area, and is not vague in 

 outline. Female marked as male. In both sexes ventral thoracic 

 sclerites and legs except femora in part, blackish; abdomen brown or 

 broAvnish yellow. Vertex coarsely, somewhat sparsely punctate; 

 punctures of clypeus slightly irregular, dense, generally not confluent. 

 Pronotum coarsely, moderately, irregularly punctate medially, punc- 

 tures becoming fine, close laterally. Minute secondary punctures 

 evenly distributed over pronotum. Lower half or two-thbds of 

 declivity of pronotal modification coarsely punctured. Scutellum, 

 usually with only minute secondary punctures. The second, fifth, 

 and eighth elytral striae obsolete, indicated by a few punctures. 

 Second stria indicated by 8 to 10 punctures, fifth and eighth striae 

 slightly more pronounced. Punctures in striae moderate, usually 

 separated by distance of about 1.5 times their diameter, without 

 setae. Epipleuron with a few long and numerous short setae. 

 Margin of elytron with only a very few long setae and a number of 

 minute ones. Mesosternal prominence in front of middle coxae 

 slightly elevated above plane of metasternum. Hair of underside 

 long and moderately dense. 



Head of male with tubercles on eye canthi and clypeus small, 

 Horn in center of vertex moderate, slightly smaller than in B. farctum 

 Fabricius, slightly bifid at tip (except in worn specimens). Head of 

 female lacks tubercle, but has carina similar to females of farctum. 

 Pronotal modification of male with transverse carina feebly emargi- 

 nate. Lateral limiting grooves shallow to moderate, lateral carinae 

 small. In the female the transverse carina less developed and evenly 

 arcuate. The lateral carinae and limiting grooves only barely 

 indicated. 



