610 PROCEEDINGS OF THE NATIONAL MUSEUM vol. in 



Description.— No detailed description of this species is warranted 

 until such time as material is available in sufficient quantity to permit 

 proper evaluation of the variation characterizing the few specimens 

 examined in the course of this study. If, when such material becomes 

 available, it can be demonstrated that the variations are such as dis- 

 tinguish population segregates that conform to our accepted species 

 concept, meaningful descriptions of prosternalis, levipennis, and any 

 other species of the complex can be prepared. 



Type data. — Horvdth's types of prosternalis were from "Brasilia: 

 Minas Geraes . . . , Cuyaba in prov. Matto Grosso." The Cuyaba 

 specimen (Hung), bearing the "Typus" label, was studied by the pres- 

 ent author. The type specimens of levipennis were from "Cajenne," 

 French Guiana, and "Amazones," Brazil; their locations are unknown. 



Distribution of specimens studied. — The seven males and three 

 females studied came from northern South America, ranging from 

 Panama to Ecuador on the west and through Venezuela to central 

 Brazil on the east. 



Discussion. — Because of the limited number of specimens avail- 

 able for this study and the number and nature of the variations in 

 structure among them, they are here placed under prosternalis for 

 reasons of nomenclatorial convenience. Indications are that two or 

 more species are represented in a complex of closely related species. 

 The following comments indicate the nature and direction of the 

 variations shown by different structures and, in a general way, pro- 

 vide information descriptive of the complex. 



The head shows several types of variations: (1) anterior outline 

 varies from a flattened semicircle through a full semicircle to a semi- 

 circle slightly prolonged anteriorly; (2) surface with no punctures or 

 numerous scattered minute punctures; (3) jugum with submarginal 

 punctures variously arranged with two close-set punctures in front 

 of eye and one puncture strongly separated apically (fig. 43), these 

 sometimes appearing in various combinations on the two sides of one 

 individual; (4) labium varying in length from between middle coxae 

 to between posterior coxae. In all specimens the pronotum has 

 the transverse impression weak but marked with a row of distinct 

 punctures, but the two lobes vary from impunctate laterally to 

 strongly abundantly punctate; all males showed a decided sinuation 

 of the side margin opposite the ends of the transverse impression. 

 The hemelytron varies in surface texture from highly polished to 

 distinctly alutaceous, and in punctation from impunctate (except 

 for usual row in clavus, one or two rows on mesocorium paralleling 

 claval suture, and punctures in impressions delimiting veins) to punc- 

 tate apically or for full length of exocorium. The scutellum varies 

 from weakly to very coarsely punctured and in one specimen shows a 



