The large Promachus and Proctacanthus group number about 12 to 15 in the state. They are included in the large Asilinae family of advanced species in the tribe Apocleini along with the large Efferia genus. All are fairly large and aggressive summertime robbers. They take butterflies and large insects seemingly without much effort. Several species seem to specifically target butterflies such as in this large buckeye kill.

Proctacanthus number 18 species in North America and I will attempt to begin adding these from all over the US as they are big and showy robbers and often noticed even by non-robber minded bug hunters. Species in this genus are:

Strictly western:

   arno Townsend  Baha CA Sur only

   coquilletti Hine  all Baha and CA only

   micans Schiner  most of the west into TX, not CA

   nearno Martin  most of the west including the upper Rockies

   nigrofemoratus Hine  SW and TX

   occidentalis Hine  BC CA NV ID

   rodecki James  plains including OK and TX to CO and ND

Eastern and widespread:

   brevipennis (Wiedemann)  most of the east including FL and into the plains and upper Rockies

   duryi Hine  OH to KS south to TX and TN

   fulviventris Macquart  FL GA

   gracilis Bromley  MS to NC to FL and GA

   heros (Wiedemann)  KY to VA south to MS and FL

   hinei Bromley  NE to NC and TX and the Rocky Mt. states

   longus (Wiedemann)  OK and TX east to NC and FL

   milbertii Macquart  most of US except far west and extreme NE

   nigriventris Macquart  NE south to AL and FL

   philadelphicus Macquart  PA and ME to GA

   rufus Williston  IA to MA south to TX and FL



Promachus number 21 species in NA. Much more concentrated in the west than Proctacanthus. The eastern species have very buzzy flight and each of the species are fairly distinct. They are separable into the tiger-striped species and the tail-light species (see photos).


   bastardii (Macquart)  entire east including IL MO MI as a western limit

   fitchii Osten Sacken  NE to MI south to TX AR and the NE (species appears to be rarer and rarer in the NE portion of the range)

   hinei Bromley  KS to OH south to TX and MS (commonest species in this area in this genus)

   quadratus (Wiedemann)  GA LA FL (similar to bastardii but more yellowed)

   rufipes (Fabricius)  IA to PA south to MS and FL (appears to be replaced by hinei west of the MS river)

   vertebratus (Say)  MO PA, likely more of the sub Great Lakes states


   albifacies Williston  WY to CA and TX (tail light species, white mystax)

   aldrichii Hine  WA ID south to CA AZ

   atrox Bromley  AZ NM

   dimidiatus Curran  Canada south to UT NM KS WI

   giganteus Hine  TX AZ NM (very large tail-light species, long wings, black and white banded abdomen)

   magnus Bellardi  TX AZ NM (big tail-light species, black abdomen, white mystax)

   minisculus Hine  TX AZ NM

   nigrialbus Martin  NV UT AZ NM TX

   nigropilosus Schaeffer  CA OR

   oklahomensis Pritchard  OK CO NE KS IN

   painteri Bromley  TX (dark wings, thick white hair on first three abdominal segments, no tail light)

   princeps Williston  WA OR CA NV UT (tail light species, white mystax)

   sackeni Hine  UT AZ NM TX (tiger-striped species with narrow bands)

   texanus Bromley  TX OK (tail light species, yellowish, short genitalia)

   truquii Bellardi  TX AZ NM (tail light species, uniformly gray)