LARVAL TAXONOMY OF THE TROGINAE IN NORTH AMERICA 39 



Mesothorax with about 5 to 7 setae on lateral lobe. Infraepisternal 

 area usually without setae; infraepimeral area with about 3 to 4 setae. 



Metathorax usually with 1 to 3 setae on anterior lateral lobe and 

 about 4 to 6 setae on posterior lateral lobe. Infraepisternal area usually 

 without setae; infraepimeral area with about 2 to 4 setae. 



Abdomen (dorsal aspect) with DLl of segments 1 through 4 with 

 transverse band of about 22 to 36 spinules; DL3 with transverse row 

 of about 5 to 14 spinules. Segment 7 with transverse row of about 24 

 to 36 spinules on DLl; DL2 with transverse row of about 4 to 10 

 spinules plus setae; DL3 usually with about 4 to 10 reduced spinules or 

 setae. 



Abdomen (lateral aspect) with segments 1 to 8 usually with 1 to 4 

 setae on LLl ; LL2 usually with 2 to 5 setae; LL3 usually with 1 to 4 

 setae. 



Generic Description of Omorgus Larvae 



Larvae of this genus may be characterized as follows: Cranium 

 (figs. 24 and 25) red brown or brown to black, reticulate posterior to 

 posterior frontal setae, slightly rugose anterior to posterior frontal 

 setae. Oval, slightly raised, nonpigmented eyespot near base of each 

 antenna. One (rarely 2) dorsal epicranial seta on each side and 10 or 

 more setae near each antenna. Frons with paired posterior (lacking in 

 0. fuliginosus), median, exterior, and anterior setae. Each anterior 

 angle with about 4 to 15 setae; setae usually arranged in 2 groups. 

 Frontoclypeal suture distinct. Postclypeus as dark as or darker than 

 cranium, with 3 (rarely 4) long setae on each side. Preclypeus light 

 yellow brown, glabrous. Labrum (fig. 57) synmieti'ical, darker than 

 preclypeus, distal margin bilobed. With paired median, lateral, antero- 

 lateral, and anterior setae. Antennae (figs. 2 1 and 25) three-segmented, 

 terminal segment much reduced. Segment 2 with distal, slightly de- 

 pressed, crescent-shaped sensory area. Segment 3 with terminal group 

 of 6 small sensory pegs. Epipharynx (figs. 9 and 11) with about 20 or 

 more stout setae along anterior border on each side of corypha. Clithra 

 present. Corypha with 4 prominent setae arising from pronounced 

 marginal tubercles. Haptomerum at least partially sclerotized, with 

 central, elevated, lightly sclerotized sensory area usually with 2 

 (rarely 3) smaller sensory spots slightly distad of 2 larger, setiferous 

 sensory spots. Sensory area usually flanked by or contiguous with 

 smaller, lightly sclerotized area on each side. Each smaller area with 

 single seta. Sclerotized portion of haptomeral region usually giving rise 

 posteriorly to slightly curving, sclerotized band on each side of pedium. 

 Sclerotized band less prominent anteriorly in some species, becoming 

 more prominent posteriorly and terminating at fused phobal mass on 



