Empis (Enoplempis) enodis Melander

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 : 416-418

Empis (Enoplempis) enodis Melander

( Figs 6 E, 8A, 18B)

Empis enodis Melander, 1902: 303 . Type locality: Chicago, Illinois, USA.

Type material examined. LECTOTYPE (here designated in order to fix identity of the species) ♂, labelled: “Chicago, Ill./ May 30 '99”; “ E. enodis / TYPE Mel”; “ALMelander/ Collection/ 1961”; “ LECTOTYPE / Empis enodis Melander / des. Sinclair, Brooks &/ Cumming 2013 [red label]” (USNM). PARALECTOTYPES: Same data as lectotype (2 ♂, 2 ♀, AMNH, 2 ♂, USNM).

Additional material examined. USA. Iowa: Buffalo Center, 18.v.1928, G.S. Walley (3 ♂, 2 ♀, CNC); Thompson, 18.v.1928, G.S. Walley (3 ♂, 2 ♀, CNC). Minnesota: Ramsey Co. (1 ♀, USNM).

Taxonomic notes. This species was described from an unspecified number of male and female specimens from two localities (i.e., Glen Ellyn and Chicago, Illinois). Only five males and two females from Chicago were located. There are two unlabelled specimens collected on 21 and 30 May 1899 (1 ♂, 1 ♀, USNM) that are possibly the missing “Glen Ellyn” syntypes. The designation of the lectotype clearly establishes the identity of this species.

Diagnosis. This species is distinguished by absence of modifications of the male hindlegs, hypandrium produced apically with cluster of short basal setae and phallus stout throughout.

Re-description. Wing length 5.5–6.0 mm. Male. Head dark in ground-colour, with dense greyish pruinescence on face, frons and occiput. Dichoptic, eye with ommatidia of similar size. Frons divergent towards antennae; below ocellar triangle nearly 2× wider than anterior ocellus, bearing short, dark setulae along inner margin of eye. Face slightly divergent towards mouthparts; bare with oral margin pale and shining. Ocellar triangle dark, subshining, with pair of short, parallel ocellar setae and pair of shorter posterior setae. Occiput bearing row of postocular setae, stout and black on upper section; shorter, paler and more slender on lower section; occipital setae black, long and stout. Postpedicel, stylus, scape and pedicel dark. Scape about 2× longer than pedicel; postpedicel more than 4× longer than basal width, more than 3× longer than stylus. Palpus yellow, with setulae dark. Proboscis largely reddish yellow; apex and base of labrum reddish brown; labellum with dark setae.

Thorax dark in ground-colour, largely densely grey pruinescent; apex of postpronotum yellowish and shiny. Scutum with pair of distinct dark, brownish vittae between acr and dc rows; distinct pair of vittae lateral to dc and above notopleural depression. Pleura grey, lacking yellowish margins on some sclerites. Proepisternum with several short, dark setae; prosternum bare. Antepronotum with row of short, stout dark setae. Postpronotum with 8– 10 short, dark setae and 1 long seta. Scutum with inconspicuous, sparse irregular row of fine acr setulae; dc longer and stouter than acr, increasing somewhat in length posteriorly; 2 posterior npl, with several anterior npl setae; 1 presut spal and several shorter dark setae; 1 psut spal; 1 pal and 1 shorter seta. Scutellum with pair of sctl, longer than pal, with 1 pair of outer marginal setae, 0.5× length of inner setae. Laterotergite with 3–4 long dark stout setae. Anterior and posterior spiracles yellowish.

Legs long, entirely yellow, except for dark ring at trochanter-femur junction and apices of femora; tarsi becoming darker apically. Coxae with numerous dark lateral and apical setae, longer and stouter along apical anterior margins. Hind trochanter lacking spine-like or modified setae. Fore and mid femora lacking posteroventral row of setae; hind femur unmodified, stout, thickened apically; 2–3 preapical antero- and posteroventral and several preapical setae ( Fig. 6 E). Fore tibia clothed in long dark setae, shorter than width of tibia; several stout erect setae on dorsal and posterior faces, and apex. Mid tibia clothed in long dark setae, shorter than width of tibia; 4–6 antero- and 2–3 posteroventral, 4–5 antero- and posterodorsal, and several preapical setae. Hind tibia unmodified, with 2 anterior, 5–6 antero- and posterodorsal, 3–5 antero- and posteroventral setae and several preapical setae ( Fig. 6 E). Tarsomeres 1–5 of all legs with rows of antero- and posteroventral spine-like setae; fore tarsomere 1 slender, not swollen and lacking long outer setae.

Wing clear with yellowish veins; all veins complete (except Sc), well sclerotized. Basal costal seta short, inconspicuous, slightly stouter and longer than surrounding costal setae. R5 and M1 somewhat divergent near wing margin; R5 ending beyond wing tip; radial fork acute. Halter yellow.

Abdomen slightly more brownish than thorax, tergites and sternites concolorous; marginal setae long on all tergites, shorter and paler on apical segments. Marginal setae on segment 8 longer and darker than preceding segment. Pregenital segments unmodified; sclerites of segment 8 narrowly separated laterally, not weakly sclerotized dorsally. Terminalia ( Fig. 8 A) largely yellow. Cercus narrow, slightly appressed to dorsal margin of epandrium, linear, broader at anterior end; dorsal inner margin with tooth-like subapical projection; posterior end truncate, not arched medially; clothed in setae, longer than width of cercus. Hypoproct with long setae. Epandrial lamella subquadrate, posterior margin rounded, bearing long subapical setae, subequal to setae on hypandrium. Hypandrium longer than 0.5× length of epandrium, with rounded apical margin; base with cluster of dark setae, shorter than hypandrium. Phallus with broad base, apical portion strongly recurved; broad throughout; apex expanded, spoon-like; apex emerging beyond cercus; ejaculatory apodeme longer than length of epandrium; inverted Y-shaped, with short median keel.

Female. Similar to male, except as follows: frons slightly broader; cercus long and slender, longer than tergite 8.

Geographical distribution and seasonal occurrence ( Fig. 18 B). Empis (En.) enodis is known from Minnesota, Iowa and northern Illinois. Adults have been collected from mid to late May.

Nuptial gift presentation. Form unknown.

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 8. Male terminalia, lateral view of E. (Enoplempis). A, E. enodis; B, E. gladiator.

FIGURE 18. Distribution of E. (Enoplempis). A, E. nuda and E. prodigiosa; B, E. enodis, E. montywoodi, E. pectinata, and E. penicillata.