Rhoptobaris

Prena, Jens, 2012, A Review of RhoptobarisLeConte (Coleoptera: Curculionidae: Baridinae) from North and Central America, The Coleopterists Bulletin 66 (3), pp. 233-244 : 239

KEY TO THE SPECIES OF RHOPTOBARIS

1. Prosternum with antecoxal portion distinctly tumescent and medially sulcate; protibial spine minute; rostrum 1.16–1.28X (male) or 1.19–1.58X (female) longer than pronotum; female tergite VII longer than wide ( Fig. 13 ), projecting far from underneath elytra.............2

1′. Prosternum with antecoxal portion slightly tumid and medially at most with subtle depression; protibial spine approximately half length of tarsal claw; rostrum 1.00–1.14X (male) or 1.09– 1.20X (female) longer than pronotum; female tergite VII not longer than wide ( Fig. 14 ), slightly projecting from underneath elytra....... 3

2. Female rostrum subtly curved to almost straight; antennal club approximately as long as funicle; elytral interstriae mostly flat, usually with 2 irregular rows of dingy white setae (1 in small specimens), setae not on tubercles; tibia with erect setae, appearing noticeably bristly; widely distributed in United States west of Mississippi River and adjacent parts of Canada................... ............................................... R. scolopax (Say)

2′. Female rostrum moderately curved; antennal club 1.2X longer than funicle; elytral interstriae convex in distal half, with 1 row of fine, light brown to dingy white setae, each on subtle tubercle; tibia with more or less appressed setae, not appearing bristly; Arizona, Mexico, Honduras................... R. cylindrifera (Casey)

3. Elytral interstriae with 2–3 irregular rows of squamiform, whitish setae; sclerolepidia little prominent, not peg-like; development in pods of Mentzelia species ; United States (Central Plains and western flank of Rocky Mountains) ................ R. canescens LeConte

3′. Elytral interstriae with 1 row of fine, whitish or brown setae; sclerolepidia noticeably prominent, peg-like; development usually in stem and root of Mentzelia species (unknown for R. obrieni ); southwestern United States (Arizona, Texas), Mexico, Central America ................. 4

4. Size 2.1–2.6 mm; funicle distinctly longer than antennal club; pronotal punctures separated from each other by at least their own diameter; Mexico, Honduras, El Salvador..... ...................... R. obrieni Prena , new species

4′. Size 2.7–3.2 mm; funicle approximately as long as antennal club; pronotal punctures separated from each other by less than their own diameter; Mexico, southwestern United States (Arizona, Texas) ............. R. piercei Prena , new species

Figures

Figs. 11–14. Tergites and abdominal ventrites of Rhoptobaris species. 11) Ventrites III–V, R. scolopax, male; 12) Ventrites III–V, R. scolopax, female; 13) Tergite VII, R. scolopax, female; 14) Tergite VII, S. canescens, female. Not to scale.