Key to the Laphria of Arkansas and the East
This key was created by modifying the key to the Laphria that appears in the 1975 paper "A Taxonomic Study of the Asilidae of Michigan" by Norman T. Baker and Roland L. Fischer. Species that do not occur here were removed and species that possibly occur here or in adjacent states were worked in by characteristics. Several large species appear at the initial added portion. Some of the redescriptions from Bullington's Laphria page were helpful in placing some of the non-Michigan species and for characters in some of the larger robbers. Links from the species names are to Bullington's redescriptions. Note that there are likely several undescribed species among the larger species Laphria sensu strictu that Bullington noted, which have not been formally published or named.
1 Fly with prominent deaths head pattern of dark on the dorsal thorax; orange waspy insect of the pine forests and coastal plain.
1 Fly without above pattern.
2 Large flies, 24 mm or more in length.
2 Smaller flies, many less than 20mm.
3 Visible dorsum of all abdominal tergites except 5 entirely bare, some hairs present along extreme lateral margins of all tergites; in the male all of these lateral hairs are black; in the female some of the hairs on tergites 1-2 are yellow.
3 Dorsum of some or all tergites other than 5 with hair.
4 Tufts of hair in front of wings entirely pale.
4 Tufts of hair in front of wings black or mostly black.
4.5 Abdominal tergite 6 covered with red hair in female.
4.5' Abdominal tergite 6 yellow haired as well as 4 and 5.
5 Entire length of dorsal half of each mid-tibia with extremely conspicuous yellow hairs.
5 Mid-tibias black.
6 Light hairs very dirty yellow to brownish yellow; tufts of hair in front of halteres with some black; very large to huge(27-39 mm long).
6 Light hairs bright to dull yellow ; tufts of hair in front of halteres entirely dull yellow; large to huge (23-35 mm long).
7 Abdomen always with considerable amounts of erect long black pile; pile of mesonotum always dense and erect; abdomen broadened beyond middle and generally ovate in males.
7 Abdomen devoid of pile or with yellow or golden pile and very little or no black pile, frequently appressed; mesonotum naked or with more or less appressed pile; abdomen almost always nearly parallel sided in males.
8 Hair on sides of first abdominal segment largely black.
8 Hair on sides of first abdominal segment largely yellow.
9 Front and middle legs and joint of metafemora and tibiae densely covered with yellow hair or fore and mid-tibia yellow haired or midtibia only yellow haired.
9 Legs largely black-haired or profemora alone with dense yellow hair.
10 Beard entirely yellow or eye margin black and rest yellow.
10 Beard black top third, yellow lower 2/3.
11 Tuft of hairs in front of halteres mostly yellow.
11 Tuft of hairs in front of halteres black.
12 Beard entirely black or nearly so.
12 Beard entirely yellow or yellow except lower margin black continuous with eye line.
13 Mystax entirely yellow.
13 Mystax all or largely black.
14 Lateral of tergite 2 and dorsum of tergites 3 and 4 always yellow.
14 Abdomen usually all black but sometimes with some yellow on 2, 3, 4.
15 Marginal scutellar bristles largely pale; disc of scutellum with black hair or entirely yellow hair.
15 Scutellar bristles and hair largely black.
16 Abdominal tergites 4 and 5 yellow; mesonotum entirely covered with long yellow hairs, two thirds of which are recumbent.
16 Abdominal tergites 4 and 5 black; mesonotum with pile appearing bright yellow from a distance, equal numbers of hairs erect or recumbent.
17 Scutellar vestiture black; black hairs far outnumber any lateral yellow hairs; pile of tergite 6 grayish to pale yellow.
17 Scutellar vestiture yellow, sometimes central smaller hairs black and lateral large hairs yellow.
18 Pile of tergite 6 grayish to pale yellow; tergites 1-4 with short black hairs; 10-16 mm insect.
18 Pile of tergite 6 black (as well as 5 and 7); tergites 1-4 yellow haired; over 22 mm long.
19 Pile of tergite 6 always black; dorsal abdominal pile of first three tergites black; tergites 2-7 entirely black haired.
19' Pile of tergite 6 all yellow; tergites 4 and 5 entirely covered with yellow hair.
19" Pile of tergite 6 black; tergites 1-3 in both sexes long yellow haired as well as part of 4, the rest black.
20 Dorsum of abdomen with entirely black pile.
20 Dorsum of abdomen with black and yellow pile.
21 Pronotal bristles black; hairs on disc of scutellum conspicuous and yellow.
21 Pronotal bristles yellow; hairs on scutellum black and slanted 45 degrees back.
22 Abdominal tergites largely covered with reddish or yellowish pile.
22 Abdominal tergites nearly bare except for more or less dense hair laterally or with only scattered fine whitish or yellowish pile on anterior margins (canis complex).
23 Femora and tibiae rather bright red-orange on all legs. Abdomen with golden pile contrasting with the darker thorax.
23 Femora and tibiae not red.
24 Mesonotum uniformly covered with golden or reddish orange, no posterior triangle present on thorax.
24 Mesonotum with extensive black pile either covering dorsum or anteriorly at the sides, light pile of thorax concolorous with abdominal pile, or mesonotum yellow haired with the pale pile on the posterior thorax forming a narrow triangle.
25 Posterior pronotum black haired; beard and coxal hair usually white; abdominal tergite 7 of female mostly black haired.
25 Posterior pronotum with golden hair; beard and coxal hair yellow; abdominal tergite seven of female mostly golden haired.
26 Abdominal tergite 6 with two well defined blunt apical processes; apical processes of the hypandrium convergent.
26 Abdominal tergite 6 with a single minute median process; apical processes of hypandrium divergent.
27 Hypopygium wider than tergite 6 when viewed from above; tergite 7 triangular rugose.
27 Hypopygium not wider than tergite 6; tergite 7 not rugose.
28 Tip of hypandrium tapering and bluntly pointed; tergite 7 distinctly keeled.
28 Tip of hypandrium expanded and leaflike; tergite 7 with small bilobate process.