Key to genus LONCHAEA and EAROMYIA . District of Columbia U.S.A.
Adapted and updated : Malloch and McAtee 1924. Keys to flies of the families Lonchaeidae, Pallopteridae, and Sapromyzidae of the eastern United States, with a list of the species of the District of Columbia region. Proceedings of the United States National Museum, 65(2525): 1-26, 2 pls..
1. Frons in both sexes with large irregular pits or depressions; a strong bristle near anterior margin of cheek … Dasiops vibrissata (Malloch)
- Frons impunctate or almost so, not pitted ………………………. 2
2. Proepimeron; Several bristly setulae surrounding the seta ……………………. 3
- Proepimeron; the single seta standing alone …………………………………………. 11
3. Calypterae; fringes black or fuscous …………………………………….. 4
- Calypteres; fringes white or yellow ………………………………………….. 9
4. Lunule bare. Antennae; postpedicel much less than 2x as long as wide. Aculeus ovipositor very wide ……………… Earomyia aterrima Malloch.
- Lunule setulose, Antennae; postpedicel > than 2x as long as wide ........................ 5
5. Eyes; in both sexes distinctly hairy, in the male conspicuously so. Wing; second costal division very long. Scutellum; disc setulose …………………………..……………. 6
Eyes; bare or almost so ………………………………………………………………. 7
6. Anepimeron; setulose centrally; Genae; with dense, short, erec,t fine hairs … L. pleurlseta Malloch.
- Anepimeron; bare; Genae; with longer setulose hairs ….......……… L. ursina Malloch.
7. Legs; Tarsi entirely black …………………………………………….. L. atritarsis Malloch.
- legs; Tarsi largely yellowish …………………………………………………………. 8
8. Orbital plate; several long fine setulae above the seta; Genae, frons, and mesonotum with rather dense erect black setulae; Wings; whitish or yellowish, infuscated at base; Scutellum with some long erect setulae on disc near apex as well as on margins; Anepimeron usually with 1 / 2 long setulae centrally………. L. hirta Malloch.
- Orbital plate; bare or with a single setula above seta; Genae, frons, and mesonotum with sparser black setulae; Scutellum generally bare on disc anepimeron bare ………………………………………………………………………….. L. affinis Malloch.
9. Antennae; postpedicel little longer than wide. Scutellum; four strong setae and no setulae. Face of male silvery ; Female; aculeus nearly as broad as frons, acutely pointed at apex, the preapical setulae very short ; auxiliary vein nearly fused with first at apex. ……….. L. arkansensis Malloch
- Antennae; postpedicel approx. 3x as long as wide. Scutellum; margin with fine setulae in addition to the usual 4 setae. Face of male not silvery. Female aculeus slender, very much narrower than frons ……………………………. 10
10. Orbital plate; upper portion glossy black; orbital seta not proximad of anterior ocellus. Genae with dense short stiff setulae. Antannae; postpedicel less than 3x as long as wide, almost entirely orange red. ………….......................… L. ruficornis Malloch.
- Orbital plate; upper portion glossy blue; orbital seta distinctly proximad of anterior ocellus. Genae with some short setulae and one or two longer setae. Antennae; postpedicel over 3x as long as wide, basalr half or more blackened. legs; hind femur with several long anteroventral setae on apical half …………. L. winnemanae Malloch.
11. Female; Aculeus; nearly as wide as frons. Calypteres and fringes white. Legs; tarsi largely yellowish; Scutellum; without fine setulae ......................... L. arkansensis Malloch.
- Female; Aculeus; slender, much narrower than frons. Scutellum usually with fine setulae in addition to the 4 setae ………………….. 12
12. Face and parafacials when viewed from above conspicuously whitish pruinescent ; frons of female dark steel-blue, shining, sparsely and evenly haired, and with a transverse depression midway between anterior margin and anterior ocellus ; third antennal segment but little longer than wide ; a strong curved bristle near anterior margin of cheek ; tarsi slightly pale basally; calyptrae and their fringes brown; no fine hairs on scutellum ……. L. albiceps Malloch.
- Face but little whitish pruinescent when viewed from above; frons not steel-blue, and without a transverse depression; cheek either without a strong bristle or with several …………… 13
13. Legs; entirely black …………………….. 14
- Legs; At least the bases of tarsi yellowish …. 17
14. Calypteres; fringes brown or fuscous …………….. 15
- Calypteres; fringes white; Genae; without strong setae ………………….. 16
15. Genae; with four outstanding setae; Scutellum; no setulae between the scutellar setae; Frons slightly bluish or greenish; Antennae; popstpedicel about 1.5x as long as wide ……… L. quadrisetosa Malloch.
- Genae; without outstanding setae; Scutellum; some fine hairs between the apical pair of setae. frons black ……………… L. angustitarsis Malloch.
16. Scutellum; Some fine setulae between the apical pair of scutellar setae. ........L. vaginalis Fallen. (Probably not this species)
- Scutellum. no setulae between the apical pair of scutellar setae …...... L. marylandica Malloch.
17.Lunule bare; Calypteres; fringes brown; Frons; with two series of incurved setulae on centre; Orbital plate; glossy upper portion microscopically strigose ………… Earomyia aberrans Malloch.
- Lunule setulose; (except in nigrociliata); Calypteres; fringes whitish or yellowish (except in nigrociliata and subpolita); Orbital plate; glossy portion of upper orbits usually smooth (compare occidentalis and coloradensis) ……… 18
I8. No minute hairs between the apical pair of scutellar bristles; third antennal segment not or barely over twice as long as its greatest width ………………… 19
- Some minute hairs between the apical pair of scutellar bristles; third antennal segment more than twice as long as its greatest width …………………….. 20
19. Tarsi brown ; larger species, fully 4 mm. in length ....…. L. marylandica Malloch.
- Tarsi pale yellow; smaller species, less than 4 mm. in length...... L. laticornis Meigen. (Probably not this species)
20. Fringes of calyptrae fuscous ………… 21
- Fringes of calyptrae white or yellow; thorax and abdomen bluish ……. 22
21. Frontal lunule bare; head and thorax black, abdomen slightly bluish ………… Earomyia nigrociliata Malloch.
- Frontal lunule hairy; thorax and abdomen blackish blue ……… L. subpolita Malloch.
22. Width of male frons at anterior margin equal to at least half the entire length of frons ; preapical dorsal pair of hairs on ovipositor very long hairs at angle of calyptrae much longer than rest of fringe; upper orbits largely microscopically strigose ………………………………………………….. L. occidentalis Malloch.
- Width of male frons at anterior margin not nearly equal to half its entire length; preapical dorsal hairs on ovipositor very short; fringes of calyptrae of uniform length …………….. 23
23. Third antennal segment about twice as long as wide; upper frontal orbits granulose ……………… L. coloradensis Malloch.
- Third antennal segment at least three times as long as wide; upper frontal orbits largely or entirely polished …………….. 24
24. Only the basal segment of each tarsus yellow ………… L. longlcornis Williston.
- Basal two or three segments of each tarsus yellow …………………………. 25
25. Larger species, over 4 mm. in length; hypopygium as in Figure 3 …….. L. nudifemorata Malloch.
- Smaller species, less than 4 mm. in length; hypopygium of male as in gure 1 ………………. L. polita Say.