Knowltonia atrifasciata (LeConte), new combination

Chrysobothris atrifasciata LeConte, 1873:332; Knull, 1970:263; Nelson, et al., 1981:139.

As we consider it here, this taxon seems to be the most variable in the genus, and it may either be polytypic or contain more than one species. The color ranges from green (usually), often with coppery reflections, to, rarely, bluish or dark coppery brown. Each elytron bears three violaceous black fasciae that are variable in size but almost always boldly distinct. Based on our current work, the only reliable records for this species in the literature are from Colorado and New Mexico. We have seen specimens from TEXAS, El Paso Co., Exit 49, I- 10, 2 mi E Fabens, 21-V-81; Garza Co., Post, 11-V-78, RLWE; Hudspeth Co., 5-5.1 mi E Salt Flat, 24-VI-70, 19-VI-71 & 29-VI-72, on grass tops and Atriplex sp., ASUC, RLWE, WFBM; Loving Co., Mentone, 1-VI-78, RLWE; Pecos Co., 18 mi W Sanderson (Terrell Co.), 30-VI-85, sweeping Atriplex canescens, FMBC in WFBM; and UTAH, Garfield Co., Grand Staircase-Escalante Natl. Mon., Calf Creek Cmpgd., lower falls trail, 37°47’37”N, 111°21’18”W [this should be 111°24’54”], 18-VII-2001, BYUC; San Juan Co., Dry Valley BLM exclosure, 34 mi S Moab, 20/VI-4/VII-87, malaise trap burned in fire, RLWE. In addition, we have examined a small series taken on Atriplex canescens in New Mexico, Hidalgo Co., 12 mi N Rodeo, 25-VI-73, ASUC. These specimens are generally a more deep green, lacking coppery reflections and the elytral markings average larger in size than on most other specimens we have seen.

Wickham’s (1898) report of this species from Yuma, Arizona, Fisher’s (1942) records and Nelson’s (1959) record of it from California on A. lentiformis all refer to K. calida . The listings from Nevada by Fisher (1942) and California by Walters (1975) should instead be referred to K. biramosa . Beer’s (1949) rearing record from Atriplex sp. in Nevada was based on a misidentification of K. biramosa . We studied the specimen recorded as A. atrifasciata from Puerto Peñasco, Sonora, Mexico by Nelson et al. (1981). It is a female. Lacking the associated male, it is impossible to ascertain the species. However, we examined a male from a nearby locality and it comes closest to the green forms of C. biramosa . Without more specimens for study the listing of either species from Sonora is questionable.