Empis

Sinclair, Bradley J., Brooks, Scott E. & Cumming, Jeffrey M., 2013, Revision of the Empis subgenus Enoplempis Bigot, east of the Rocky Mountains (Diptera: Empididae), Zootaxa 3736 (5), pp. 401-456 : 403-404

Empis ( Enoplempis Bigot )

Enoplempis Bigot, 1880a: 63 [1880b: xlvii]. Type-species, E. mira Bigot (monotypy) (Evenhuis & Pont 2004).

Diagnosis. Typical features of the subgenus are as follows: male head dichoptic to nearly holoptic; face and prosternum bare; labellum setose, short and fleshy, not prolonged; acrostichals and dorsocentrals usually short; apical scutellar setae often widely separated; wing (Figs 2A, B) with M1 and M2 complete to wing margin, anal vein (CuA+CuP) complete (reaching wing margin) or incomplete, axillary excision acute to obtuse, axillary lobe well or little developed; male hindleg frequently modified with tibia and femur variously armed with tubercles, lobes, series of prominent setae, or bristle pencils (e.g., Figs 6 , 9 , 12 , 16 , 23 ); right and left hindlegs normally symmetrical; tarsomeres 2–5 of all legs (in both sexes) usually with 2 ventral rows of short spine-like setae (Figs 2C, D, E); tarsomere 4 usually with apicolateral pair of spine-like setae; male pregenital segments generally unmodified, except some western species; ejaculatory apodeme in anterior view, often inverted Y-shaped, rarely Tshaped or flattened; female without most empidine secondary sexual features, such as expanded and darkened wings, pinnate leg scales, and silvery abdominal pruinesence; extensive eversible darkened abdominal pleural membrane observed in females of some species.

Remarks. The subgenus Enoplempis is most readily identified from other Empis subgenera by paired rows of ventral spine-like setae on the tarsi, which appears to be correlated with characteristic post-mortum tarsal curling seen in most museum specimens (Figs 2D, E). These spine-like setae are reduced in some species (see species group description) and are not unique to E. ( Enoplempis ). Rows of ventral tarsal spines also occur in some species of other subgenera of Empis , such as various E. ( Coptophlebia ) s. lat. (from North America and Japan) and E. (Kritempis) livida L. (not as pronounced in females). Empis (En.) can be tentatively divided into the following three broad species groups, although final decisions on the monophyly and relationships of these groups must wait until the western species are fully analyzed.

(1) The E. (Enoplempis) mira -group includes three species with male hindlegs highly modified and bilaterally asymmetrical; hind tibia geniculate at base in both sexes; acrostichals biserial; dorsocentrals uniserial; apical scutellar setae closely positioned; ventral tarsal spine-like setae absent. This group is recorded from Idaho, Oregon and California.

(2) The E. (Enoplempis) geneatis -group includes at least two species and is characterized by unmodified male hindlegs; long setae on scape, palpi and back of head; acrostichals and dorsocentrals multiserial; apical scutellar setae closely positioned. This group is known from Oregon and California.

(3) The E. (Enoplempis) bigoti -group comprises over 40 species and is usually characterized by modified male hindlegs (tibia, femur and/or trochanter and coxa); apical scutellar setae widely separated; acrostichals and dorsocentrals uniserial and reduced; tarsal spine-like setae very pronounced. This group is widespread across North America.

The eastern species of E. ( Enoplempis ) all belong to the large E. (Enoplempis) bigoti -group. They can be further classified into at least four subgroups as indicated below under “Discussion”.

Figures

FIGURE 6. Male legs of E. (Enoplempis). A, E. arthritica, hindleg, anterior view; B, E. arthritica, apex of hind femur and base of hind tibia, anterior view; C, E. arthritica, apex of hind femur and base of hind tibia, posterior view; D, E. ctenocnema, hindleg, anterior view; E, E. enodis, hindleg, anterior view.

FIGURE 9. Male legs of E. (Enoplempis). A, E. gladiator, apex of hind femur and base of hind tibia, anterior view; B, E. gladiator, apex of hind femur and base of hind tibia, posterior view; C, E. gulosa, hindleg, anterior view; D, E. gulosa, hind trochanter, anterior view; E, E. loripedis, hindleg, anterior view; F, E. loripedis, apex of hind femur and base of hind tibia, anterior view; G, E. loripedis, apex of hind femur and base of hind tibia, posterior view.

FIGURE 12. Male legs of E. (Enoplempis). A, E. montywoodi, apex of hind femur and base of hind tibia, anterior view; B, E. montywoodi, apex of hind femur and base of hind tibia, posterior view; C, E. nodipoplitea, apex of hind femur and base of hind tibia, anterior view; D, E. nuda, hind trochanters; E, E. nuda, hindleg, anterior view.

FIGURE 16. Male legs of E. (Enoplempis). A, E. pectinata, hindleg, anterior view; B, E. penicillata, hindleg, anterior view; C, E. prodigiosa, hindleg, anterior view; D, E. prodigiosa, apex of hind femur and base of hind tibia, anterior view; E, E. prodigiosa, apex of hind femur and base of hind tibia, posterior view.

FIGURE 23. Male legs of E. (Enoplempis) volsella. A, hindleg, anterior view; B, apex of hind femur and base of hind tibia, anterior view; C, apex of hind femur and base of hind tibia, posterior view.