Empis (Enoplempis) canaster Melander

Empis (Enoplempis) canaster Melander

( Figs 85–88 View FIGURES 82–90 , 100 View FIGURES 100–101 , 129 View FIGURES 129–130 )

Empis canaster Melander, 1902: 326 . Type locality: Moscow , Idaho ( USA), by lectotype designation.

Empis (Enoplempis) canaster : Melander, 1928: 142 (assigned to subgenus Enoplempis ).

Empis canaster : Melander, 1965: 459 (catalogue); Yang et al., 2007: 132 (catalogue).

Type material examined. LECTOTYPE (here designated in order to fix identity of the species) ♂, labelled: “ Moscow [46°48ʹN 116°52ʹW]/ Idaho ”; “ W.M. Wheeler,/ Collection.”; “ TYPE / No. A.M.N.H. [red label]”; “ Am. Mus . Nat. Hist./ Dept. Invert. Zool./ No. 977”; “ LECTOTYPE / Empis canaster Melander / des. Sinclair, Brooks &/ Cumming 2025 [red label]” ( AMNH) . PARALECTOTYPES: USA: Idaho: Same data as lectotype (1♂, 1♀, AMNH; 2♂, USNM) .

Notes on type specimens. This species was based on seven males and one female specimen from Idaho and Oregon ( Melander 1902) . Four male syntypes and one female syntype from Idaho were identified .

Additional material examined. USA. Idaho: Latah County: Laird Pk , 1.3 mi. E, 14.v.1962, WFB (1♂, WFBM) ; Moose Ck Rd nr Bovill , 46.868°N, 116.406°W, 870 m, 9.vi.2009, I.S. Winkler, E09-63a, EPL-13 (1♂, CNC) GoogleMaps ; Paradise Ridge , 46°39′36.7″N 117°22′19.3″W, 31.v.2022, A. Hawse, ex Lomatium multiflorum (2♂, CNC) GoogleMaps ; Potlach [46°55′N 116°53′W], 28.v.193?, J.M. Aldrich (1♂, USNM) GoogleMaps .

Diagnosis. This species is distinguished from other species of the E. (En.) canaster species group by two paint brush-like preapical ventral lobes on the male hind femur, single digitiform basal process on the male hind tibia, and length of dorsal setae of the male hind tibia twice width of tibia ( Figs 85–87 View FIGURES 82–90 ).

Redescription. Wing length 6.2–7.5 mm. Male. Head dark in ground-colour, with greyish pruinescence. Dichoptic, upper ommatidia not enlarged. Frons divergent towards antennae; narrowest section of frons equal to width of anterior ocellus; with short setulae along inner margin of eye. Face without setae; slightly divergent towards mouthparts, with oral margin dark and shiny. Ocellar triangle elevated, with thin greyish pruinescence, with pair of parallel ocellar setae, posterior pair half length of anterior setae and several short setulae. Occiput with single median row of strong, stiff setae, shorter than ocellar setae, longer and finer ventrally; postocular setae with upper 2–3 setae strongly curved, shorter than ocellar setae, with lower postocular setae straight, half length of upper setae; postocellar region without setae. Antenna dark; scape slightly more than 2× longer than pedicel, with short, black setae; pedicel with ring of apical setae; postpedicel long and tapered, 4× longer than basal width; stylus slightly more than 1.5× longer than basal width of postpedicel. Palpus pale, yellowish brown, with dark setulae. Proboscis reddish brown, length less than 2× head height; labellum with short, dark setae.

Thorax dark brown in ground-colour, densely grey pruinescent. Scutum with 2 pairs of broad brownish vittae running between setal rows; lateral pair extending onto prescutellar depression; apex of postpronotal lobe shiny yellowish brown; postalar ridge pale brown. Proepisternum with short, dark setae on lower section; upper proepisternum in front of spiracle without setae. Prosternum bare. Antepronotum with row of 4–5 pairs of dark, stiff setae, longer laterally. Postpronotum with 1 long seta and 4–5 short, dark stiff setae. Scutum with short, fine uniserial acr; dc uniserial, slightly longer, stronger than acr, increasing in length posteriorly; 1–2 posterior npl, with 1–3 shorter anterior npl; 0 presut spal, with several setulae; 1 psut spal; 1 pal. Scutellum with 1 widely separated pair of long sctl, aligned with dc row, with 1 outer, shorter pair of marginal setulae; disc bare. Laterotergite with narrow patch of 4–5 strong, dark setae. Anterior and posterior spiracles pale.

Legs slender, yellowish brown, apex of tibiae and tarsi darker; coxae yellowish brown, often mostly clothed in dense greyish pruinescence, concolourous with pleura. Coxae with stiff, black setae. Hind trochanter with short setulae. Fore femur clothed in short, black setae. Fore tibia with 3–4 long anterodorsal and posterodorsal setae on apical third, longer than width of tibia; apical half with long posterior setae; ring of outstanding preapical setae; anterior face clothed in dense short setulae. Fore tarsomere 1 swollen, as broad as basal width of tibia, with dense setulae and long setae on all faces, longer than width of tarsomere; tarsomeres 2–5 with biserial row of spine-like ventral setae; tarsomeres 1–4 with apicolateral pair of spine-like setae, longer than width of segment. Mid femur clothed in short, black setae. Mid tibia with 3–4 posterior and posteroventral setae, subequal to width of tibia; several preapical setae surrounding apex; 3–4 anterodorsal and posterodorsal setae, subequal to width of femur. Mid tarsus similar to fore tarsus. Hind femur with 2 preapical, paint brush-like ventral processes and outer elbowed posteroventral digitiform process without setae; medial paint brush-like process broader than outer paint brush-like process; short knob-like process or ridge posterior to paint brush-like processes; apex of femur without preapical row of posterior setae; preapical anterior seta strong, shorter than width of femur ( Figs 86, 87 View FIGURES 82–90 ). Hind tibia with single, narrow posteroventral digitiform process on basal quarter, with crown of black setae; without seta in posteroapical comb; apical two-thirds with long dorsal setae, longer apically, less than twice width of tibia ( Figs 85–87 View FIGURES 82–90 ). Hind tarsomere 1 somewhat inflated, with long dorsal setae, similar to tibia; tarsomeres 2–5 similar to mid tarsus.

Wing slightly infuscate with dark veins, darker about node of radial fork; all veins complete (except Sc), well sclerotized; CuA+CuP distinctly reaching wing margin. Basal costal seta absent. R 5 and M 1 parallel near wing margin; R 5 ending slightly posterior to wing tip; radial fork acute. Halter pale, yellowish brown.

Abdomen dark, with dense greyish pruinescence, concolourous with scutum; long, pale lateral setae on pregenital segments. Pregenital segments unmodified; sclerites of segment 8 narrowly separated, weakly narrowly fused anteriorly. Terminalia ( Fig. 100 View FIGURES 100–101 ): orange brown, shiny with cercus dark brown. Cercus short, rectangular; dorsal margin slightly expanded basally; apex rounded; setae longer than width of cercus; weakly fused anteriorly to epandrium. Subepandrium without process; with row of medium-length setae. Epandrial lamella oval, higher than long; posterior margin without projection, bearing longest setae along posterior margin; some setae as long as epandrium. Hypandrium short, truncate, slightly projected laterally with arched apical margin; numerous setae of variable lengths present. Phallus very narrow and tubular basally; strongly expanded on basal half, tapered, mostly straight apically; apex not emerging beyond cercus; apex not expanded; ejaculatory apodeme longer than length of epandrium, T-shaped, with ventrally positioned lateral apodemes.

Female. Similar to male, except as follows: frons broader, nearly as wide as ocellar triangle; hindleg without modified setae and processes; abdominal pleural membrane not visible; tergite 8 shiny.

Geographical distribution and seasonal occurrence ( Fig. 129 View FIGURES 129–130 ). Empis (En.) canaster is known from Latah County in Idaho collected in May and June. Melander (1902, p. 327) also mentions additional syntype (s) from Oregon.

Nuptial gift presentation. Form unknown.