Genus Episyron


This key is constructed from H. E. Evan's Taxonomic Study of the Nearctic Spider Wasps Belonging to the Tribe Pompilini from 1951. Likely includes all expected species in this genus in Arkansas for both sexes. There is one other western species.

Females

 

1  Front basitarsus with 4 (rarely 5) comb-spines of considerable length, the basal one often smaller than the others; eyes not strongly convergent above, upper interocular distance approximately .85 X lower interocular distance; vertex not strongly raised above the tops of the eyes

quinquenotatus quinquenotatus

1' Front basitarsus with only 3 comb-spines; eyes more strongly convergent above, upper interocular distance less than .78 X the lower, or the front very broad ant eh vertex arcuately raised above the tops of the eyes

2

 

2 Third antennal segment subequal to or greater than upper interocular distance; vertex less broad than below, and scarcely raised above the tops of the eyes; ocelli in a more compact triangle, the front angle of wich is about or slightly greater than a right angle

3

 

2 Third antennal segment equal to .9 or less X upper interocular distance; ocelli forming a very flat triangle, the front angle distinctly greater than a right angle; vertex very broad, more or less arcuately raised above the tops of the eyes

snowi

 

3 Legs partly or wholly rufo-ferruginous; head and thorax with moderately abundant pale hair; tarsal comb very strong, the apical basitarsal spine about 1.5X the length of the 2nd tarsal segment

conterminus posterus

 

3 Legs black; head and thorax with abundant black hair; apical basitarsal comb-spine slightly if any longer than the 2nd tarsal segment

biguttatus biguttatus

 

Males

 

1  Marginal cell very long, less than its own length from the apex of the wing; stigma very large; apex of abdomen compressed, the subgenital plate strongly so, though the apical abdominal segments are usually telescoped into the basal ones (sometimes short-antennaed males of this species keys to this genus key)

Agenioideus birkmanni

1' Marginal cell at least its own length from the wing-tip; stigma small or of moderate size; subgenital plate not strongly compressed

Evagetes species

 

2 Subgenital plate with the median line elevated in the form of a ridge which is arcuate in profile; 3rd submarginal cell small, shorter above and below than the 2nd, sometimes petiolate

padrinus minisculus

 

2 Median line of subgenital plate only feebly elevated; 3rd submarginal cell usually at least as wide below as the 2nd

3

 

3 Front and hind wings wholly and almost uniformly deep fuliginous; submedian cell of hind wing usually broadly rounded or somewhat truncate apically, sometimes appendiculate; 3rd antennal segment about twice the length of 2nd, which is very short

ingenuus

 

3 Wings not wholly fuliginous; submedian cell of hind wing pointed or narrowly rounded apically, never appendiculate; 3rd antennal segment not twice the 2nd

4

 

4 Posterior margin of pronotum subangulate; vestiture deep blue-black, nowhere silvery; digiti of genitalia subclavate, the apex scarcely extended inward

subangulatus

 

4 Posterior pronotal margin arcuate, at most with a slight median notch; pubescence markedly bluish and/or silvery; digiti to some extent produced inward at apex

5

 

5 Propodeum without more than a very few inconspicuous erect hairs on the sides apparent above the coarse silvery pubescence; front barely to moderately hairy; digiti less strongly extended inward apically, sparsely and rather uniformly setose

parvus

 

5 Propodeum usually with noticeable dark erect hairs; front with abundant erect hairs just above the antennal bases; digiti slightly more strongly extended inward apically, clothed with numerous short setae which tend to be crowded toward the upper, outer angles

hyacinthus

 

Pompilid list