Key at a Glance

1a: Wasp extraordinarily large, to 2 inches long—about the size of a thumb; body black, sometimes shimmering blue black; wings orange.

--> Go to Pepsis sp.

1b: Wasp smaller; of various forms and colors but lacking the two characteristics of extraordinarily large size and orange wings.

--> Go to Couplet #2

2a: Wasp with distinct red velvet abdomen; wings black, often shiny, iridescent black.

--> Go to Red Velvet Scoliid

2b: Wasp of various forms but lacking the distinct red velvet abdomen.

--> Go to Couplet #3

3a: Wasp with abdomen petiolate (thread-waisted).

--> Go to Couplet #4

3b: Wasp with abdomen sessile (closely attached).

--> Go to Couplet #11

4a: Wasp with abdomen elongate, drawn out on a long stalk; when wings are resting over abdomen, nearly half of the abdomen remains uncovered.

--> Go to Couplet #5

4b: Abdomen bulb or oval shaped; attached to thorax by a thread, or appearing as two distinct pieces: the petiole and the abdomen; when wings are resting over abdomen, they cover or nearly cover the abdomen.

--> Go to Couplet #6

5a: Wasp nearly two inches long, but slender; head and thorax black; thorax with silvery marks; abdomen orange with black tip.

--> Go to Ammophila procera

5b: Wasp about ½ inch long, slender; head and thorax black; abdomen orange with black tip.

--> Go to Ammophila pictipennis

5c: Wasp about ½ inch long, slender, body completely orange-red.

--> Go to Ammophila ferruginosa

6a: Wasp completely black; wings black.

--> Go to Sphex sp., male

6b: Wasp black and red-orange; or black, amber, and yellow.

--> Go to Couplet #7

7a: Wasp yellow and brown; abdomen a yellow bulb on a thickened stalk; wings at rest are folded longitudinally.

--> Go to Eumenes sp.

7b: Wasp black or brown; abdomen orange, black and orange, or golden brown.

--> Go to Couplet #8

8a: Head and thorax black; abdomen completely orange.

--> Go to Couplet #9

8b: Head and thorax dark; face and thorax often with bright gold marks.

--> Go to Couplet #10

9a: Abdomen is red-orange and shaped like a light bulb.

--> Go to Prionyx parkeri

9b: Abdomen is red-orange and shaped like a flattened oval.

--> Go to Sphex sp., female

10a: Abdomen dark red with black rings; face, head and thorax with golden hairs; legs amber.

--> Go to Isodontia elegans

10b: Abdomen red with black tip; wasp heavily marked with glittery gold hairs; wings shimmer golden; legs red.

--> Go to Sphex ichneumoneus

11a: Abdomen distinctly narrow, narrower than thorax, and black with yellow bands.

--> Go to Couplet #12

11b: Abdomen more robust, about as wide as thorax, variously colored.

--> Go to Couplet #13

12a: Yellow abdominal bands narrow and complete; upturned hook at tip of abdomen; three yellow spots on back; yellow nose.

--> Go to Myzinum sp., male

12b: Yellow abdominal bands thick, basal band does not meet in middle; two transverse yellow lines on thorax; body covered with clear hairs.

--> Go to Crioscolia sp., male

13a: Wings are folded longitudinally; pronotum is V-shaped; eye notched along inner margin.

--> Go to Couplet #14

13b: Wings are not folded.

--> Go to Couplet #15

14a: Wasp about 1 inch long; abdomen is an elongated oval with several segments of more or less equal size.

--> Go to Polistes sp.

14b: Wasp about ½ inch long; abdomen is a bulb on a thickened stalk, the first segment is much longer than all the others together, forming a sort of skirt with the remaining segments protruding from beneath.

--> Go to Eumenes sp.

14c: Wasp about ¼ inch long; abdomen is an elongated bulb and closely attached to the thorax (not on a distinct stalk); body is black, with yellow, pale yellow, or white patches on shoulders, dorsal thorax, ventral abdomen, and face.

--> Go to Eumeninae group

15a: Wasp black or mostly black.

--> Go to Couplet #16

15b: Wasp mostly yellow, yellow and amber, or red.

--> Go to Couplet #18

16a: Wasp black all over; head and thorax with shiny, golden hairs; shiny bands across abdomen.

--> Go to Tachytes sp.

16b: Wasp variously colored; body bare; abdomen with various yellow rings.

--> Go to Couplet #17

17a: Abdominal rings yellow wide, and complete; two transverse yellow lines on thorax; two yellow lines on face along inner margin of eyes; yellow shoulder patches.

-->Go to Myzinum sp., female

17b: Abdominal rings pale yellow or whitish, not quite meeting in middle of abdomen; with four yellow spots on thorax.

--> Go to Bicyrtes sp.

17c: Abdominal rings yellow; rather than even rings, pattern is notched and undulating.

--> Go to Glenostictia sp.

17d: Abdominal rings yellow, basal band incomplete, other bands wide and complete; yellow collar and two transverse yellow lines on back.

--> Go to Ectemnius sonorensis

18a: Wasp red all over, completely lacking yellow marks.

--> Go to Tachypompilus sp.

18b: Wasp with various yellow markings.

--> Go to Couplet #19

19a: Abdomen with various yellow abdominal spots.

--> Go to Couplet #20

19b: Abdomen with various yellow abdominal rings.

--> Go to Couplet #21

20a: Abdomen with bright yellow, clearly defined spots; body with red-orange hairs often visible.

--> Go to Yellow-spot Scoliids

20b: Abdomen with abdominal pattern a mixture of spots and undulating, notched rings; thorax marked with yellow smiley face or horseshoe.

--> Go to Steniolia elegans

21a: Wasp very large, over one inch long; primarily yellow; abdomen with yellow rings.

--> Go to Robust Yellow Group

21b: Wasp smaller, ¼ to ½ inch long; abdomen with yellow rings.

--> Go to Couplet #22

22a: Abdomen narrow; thin, yellow abdominal rings alternating with wider, brown rings; abdomen smooth.

--> Go to Poecilopompilus sp.

22b: Abdomen visibly segmented, usually with prominent yellow rings alternating with thinner, black rings; if black rings present, then head is also black. Sometimes abdomen with thin, yellow bands alternating with red bands. If red bands present, then head also red.

--> Go to Eucerceris Group