Empis (Enoplempis) loripedis Coquillett

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 : 424-425

Empis (Enoplempis) loripedis Coquillett

( Figs 9 E, F, G, 10B, 14A)

Empis loripedis Coquillett, 1895: 400 . Type-locality: South Illinois, USA.

Type material examined. LECTOTYPE (here designated in order to fix identity of the species) ♂, labelled: “Robertson[collector]/ S. Illinois”; “ Type / No. 3163/ U.S. N.M. [red label]”; “ Empis / loripedis / Type. Coq. [handwritten]”; “ LECTOTYPE / Empis loripedis Coquillett / des. Sinclair, Brooks &/ Cumming 2013 [red label]” (USNM). PARALECTOTYPES: Same data as holotype (1 ♂, 3 ♀, USNM).

Additional material examined. CANADA. Ontario: Leamington, 4.vi.1937, G.S. Walley (1 ♂, CNC). USA. Illinois: Carlinville, Robertson (1 ♂, USNM); Chicago, 20.vi.1895, 9.v.1896 (2 ♂, USNM); Chicago, 18.vi.1898, W.M. Wheeler (3 ♂, 1 ♀, AMNH). Indiana: LaFayette, 16, 18, 19, 28.v., 2,10.vi., J.M. Aldrich (4 ♂,7 ♀, USNM). Michigan: Monroe, 30.v.1948, G. Steyksal (1 ♂, CNC); Mackinac Co., 4.vi.1959, R. & K. Dreisbach (1 ♀, CNC); Wayne Co., 28.v.1948, R.R. Dreisbach (1 ♂, CNC); Wayne Co., Grosse Ile., 26.vi.1955, G. Steyskal (1 ♂, USNM). Ohio: Columbus, 22–23.v.1925, R.H. Painter (2 ♂, USNM); Columbus, 13.v.1899, C.W. Johnson (1 ♂, USNM); Columbus, 30.v.1900, J.M. Aldrich (2 ♂, 1 ♀, USNM); Columbus, 30.v., 2.vi., 18.v.1899 (3 ♂, 1 ♀, USNM); Columbus, 13.v.1899, W.M. Wheeler (1 ♂, AMNH); Columbus, 30.v.1900, S.W. Williston (1 ♀, AMNH). Pennsylvania: Castle Rock, 9.vi.1907, 14.vi.1908, C.T. Greene (2 ♀, USNM).

Taxonomic notes. This species was described from five male and five female specimens, collected by C. Robertson and H.E. Weed. Two male (including the lectotype) and three female syntypes were found in the USNM. The location of the remaining three male and two female paralectotypes is unknown. The designation of the lectotype clearly establishes the identity of this species.

Diagnosis. This species is distinguished by apical half of fore tibia and apex of mid and hind tibiae dark, hind tibia with setae longer than width of segment; base of hind tibia with bare, pointed triangular and tapered process; hind femur with hooked, posteroventral preapical process, shorter than width of femur.

Re-description. Wing length 5.7–7.3 mm. Male. Head dark in ground-colour, with dense grey pruinescence on face, frons and occiput. Dichoptic, eye with ommatidia of similar size. Frons slightly divergent towards antennae; below ocellar triangle slightly wider than anterior ocellus, bearing short setulae along inner margin of eye. Face slightly divergent towards mouthparts; bare with oral margin dark and shining. Ocellar triangle with grey pruinescence, with pair of short parallel ocellar setae; posterior setulae less than 0.5× length of anterior. Occiput bearing row of postocular setae, a few stout and black setae on upper section; shorter and very slender on lower section; occipital setae black, long and stout, subequal in length to upper postocular setae. Postpedicel, stylus and scape mostly dark; extreme base of postpedicel and inner face of pedicel slightly paler. Scape more than 2× longer than pedicel; postpedicel more than 6× longer than basal width, 2.3× longer than stylus. Palpus yellow, with setulae dark. Proboscis largely yellow; apex of labrum reddish brown; labellum with dark setae.

Thorax dark in ground-colour, largely densely grey pruinescent: postpronotum, supra-alar ridge and outer lower margin of scutellum yellowish orange. Scutum with pair of faint dark vittae between acr and dc rows; faint pair of vittae lateral to dc and above notopleural depression. Pleura grey, sometimes with upper parts of katepisternum, anepimeron and meron paler and yellowish. Proepisternum grey, with several short, dark setae; prosternum bare. Antepronotum with row of short, dark setae. Postpronotum with 2–3 short, dark setae and 1 long seta. Scutum with sparse row of fine acr setulae; dc longer than acr, increasing in length posteriorly; 1 posterior npl, with several short anterior npl setae; 1 short presut spal; 1 psut spal; 1 pal. Scutellum with pair of short sctl, subequal in length to pal, lacking marginal setulae. Laterotergite with 2–4 long dark setae. Anterior and posterior spiracles pale.

Legs long, mostly yellow, except for dark ring at trochanter-femur junction and apices of femora; apical half of fore tibia and tarsus, apex of mid tibia, apex of tarsomere 1 and tarsomeres 2–5, and apex of hind tibia apex of tarsomere 1 and tarsomeres 2–5 reddish brown. Coxae with numerous dark lateral setae, longer and stouter along apical anterior margins. Hind trochanter lacking setae. Fore femora lacking distinct posteroventral row of setae; mid femur with posteroventral row of slender setae; hind femur thickened towards apex, with antero- and posteroventral rows of slender setae, length of preapical setae subequal to width of femur. Fore tibia clothed in long dark setae, shorter than width of tibia; with 5–6 anterodorsal, 2 posterodorsal, 5–7 posterior, 4–5 posteroventral setae, mostly 3× width of tibia; and several long preapical setae. Mid tibia clothed in long dark setae, shorter than width of tibia; about 6 anterior, 3–4 anterodorsal, 4–5 posterior, 4–5 posteroventral, 2 anteroventral setae, mostly 2× width of tibia; and several preapical setae. Hind femur with preapical, black anteroventral process, knob-like; inner apex with posteroventral preapical, ventrally-directed process, shorter than width of femur ( Figs 9 F, G); distal to latter process pair of preapical posteroventral hook-shaped processes directed posteriorly and posteromedially, hook of inner hook blackened; apex with short, knob-like process distal to hooked processes. Hind tibia somewhat twisted, joint with femur somewhat prolonged; base with pair of anteroventral process ( Figs 9 F, G): proximal process, long and tapered, subequal to width of tibia; distal process broad, tooth-like with sharp bifid apex; anteroventral, anterior, anterodorsal, posterodorsal and posteroventral portions with rows of long black setae of various lengths, some 2× width of tibia ( Fig. 9 E); several preapical setae present. Tarsomeres 1–5 of all legs with rows of antero- and posteroventral spine-like setae; fore tarsomere 1 somewhat swollen, wider than tibia, with long outer setae.

Wing clear with brownish veins; all veins complete (except Sc), well sclerotized. Basal costal seta inconspicuous. R5 and M1 somewhat divergent near wing margin; R5 ending beyond wing tip; radial fork acute. Halter yellow.

Abdomen dark, shining with pair of yellowish lateromedial spots on each tergite, sternites yellow; tergites with long marginal setae, longest on tergite 5. Marginal setae on segment 8 subequal to length of tergite. Pregenital segments unmodified; sclerites of segment 8 weakly fused to form complete ring, not weakly sclerotized dorsally. Terminalia ( Fig. 10 B) largely yellow. Cercus broad, well separated from dorsal margin of epandrium, posterior end prolonged into finger-like, setose process arched medially. Hypoproct lacking setae. Epandrial lamella subtriangular, posterodorsal margin produced into hook-like process (lacking pubescence) with bacilliform sclerite extending to base of process; some setae longer than half length of epandrium. Hypandrium short, not extended posteriorly with truncate margin, about 0.2× as long as epandrium; lacking setae. Phallus with broad basal 0.33, apical 0.66 gently arched dorsally and gradually tapered; apex emerging beyond cercus; ejaculatory apodeme longer than half length of epandrium; inverted Y-shaped, with median keel reduced.

Female. Similar to male, except as follows: frons slightly broader; hind femur and tibia lacking modified setae and processes; long setae reduced in number; cercus long and slender, slightly shorter than tergite 8.

Geographical distribution and seasonal occurrence ( Fig. 14 A). Empis (En.) loripedis is known from southern Ontario and the northeastern USA (Michigan, Illinois, Indiana, Ohio and Pennsylvania). Adults have been collected from early May to late June.

Nuptial gift presentation. Form unknown.

Figures

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 10. Male terminalia, lateral view of E. (Enoplempis). A, E. gulosa; B, E. loripedis.

FIGURE 14. Distribution of E. (Enoplempis). A, E. loripedis and E. nodipoplitea; B, E. vockerothi and E. volsella.