Empis (Anacrostichus) pallida Loew, 1861

Shamshev, I. V., 2023, Review of the Nearctic species of the subgenus Anacrostichus Bezzi, 1909 (Diptera: Empididae), Russian Entomological Journal 32 (3), pp. 330-355 : 338-340

Empis (Anacrostichus) pallida Loew, 1861

Figs 14, 15.

Empis pallida Loew, 1861: 322 (♂) [Cent. 1, no. 30]. Type locality: USA, New York .

MATERIAL EXAMINED. CANADA. Ontario: Waubamik, Jne’15, H.S. Parish // Empis pallida Loew (1 ♂, OUMNH).

DIAGNOSIS. Mid-sized (body about 4.5 mm) species with yellow body and legs; male eyes dichoptic; mesoscutum without acrostichal setae; hind femur slender, hind tibia and (besides circlet of subapicals). Fore tarsus with rather long hind basitarsus with numerous long, fine setae dorsally; setulae; basitarsus somewhat thickened. Mid femur with rows abdomen with fine, yellow setae. of anteroventral and longer posteroventral spine-like setae.

DESCRIPTION. Body length about 4.5 mm, wing 5.0 mm. Mid tibia with 1 anterodorsal seta. Mid tarsus with rather long Male. Body entirely yellow to reddish yellow. Head with setulae. Hind femur clothed in rather long setulae; bearing frons, face (except lower margin), ocellar triangle, occiput and spine-like ventral setae, especially in subapical part. Hind tibia postgena densely light grey pruinose; setation mostly black, bearing long, dorsal, fine setae (longer in subapical part). Hind postgena with pale setae. Eyes dichoptic, with ommatidia tarsomeres with long, dorsal, fine setae (especially basitarsus). equally small. Frons below ocellar triangle nearly 1.5 times Wing long; membrane hyaline; veins yellowish; basal broader than anterior ocellus; with scattered marginal setulae. costal seta absent. Anal lobe well-developed; axillary incision Face broader than frons, bare. Ocellar setae short. Occiput with obtuse but only slightly more 90°. Squama yellow, pale moderately long postoculars and row of similar setae on upper fringed. Halter yellow. part; postgena with hair-like setae. Antenna with scape and Abdomen with yellow, fine setae. Tergite 5 and sternite 5 pedicel yellow, postpedicel (except yellow base) and stylus with unmodified structure and vestiture. Postabdomen (Fig. 14): brown; scape nearly 2X longer than postpedicel, both with segments 6–8 modified. Tergite 6 and segment 7 bent scattered short setae; postpedicel nearly 4X longer than basal downwards, accordingly segment 8 and terminalia shifted to width. Proboscis with labrum nearly 1.5X longer than head ventral position relative to body plane. Tergite 6 asymmetrical; height. Palpus yellow, with scattered black setulae. slightly narrower than tergite 5; with small excavation at

Thorax subshiny, faintly pruinose, mostly black setose. posterior corner. Sternite 6 invisible in situ, small, entire, Prosternum bare. Proepisternum with 1 black and 3 yellow fine subrectangular (ventral view), convex mid-anteriorly, weakly setae on lower part, bare on upper part. Pronotum with 6 strong sclerotised, bare. Tergite 7 slightly asymmetrical; narrower black setae on each side. Postpronotal lobe with 1 moderately and shorter than tergite 6, with small, lateral tubercle. Sternite long inclinate and 2 short setae. Mesonotal setae: acrostichals 7 symmetrical, entire, subrectangular; with small, blackish, absent; dorsocentrals uniserial, fine, moderately long, 1 lateral tubercle posteriorly; bearing few moderately long prescutellar pair longer; 1 presutural supra-alar, 2 notopleurals, setae laterally. Segment 8 funnel-like, with entirely separated 1 postsutural supra-alar, 1 postalar, 2 scutellars. Laterotergite tergite and sternite; tergite 8 long, nearly as long as tergite 7, with black setae. Spiracles yellow. undivided; deeply, narrowly concave anteriorly, with straight

Legs very long, slender; almost entirely yellow (including posterior margin; sternite 8 rather subtriangular in lateral view, coxae), tarsomeres 1–4 brownish apically, tarsomere 5 entirely only slightly longer than tergite 8, with simple structure and brown. All femora without whitish pilosity ventrally. Fore vestiture. femur with 4–5 anteroventral and 4–5 posteroventral spine- Terminalia (Figs 14, 15) moderately large. Epandrium like setae near apex. Fore tibia without prominent setae entirely divided (epandrial bridge absent); epandrial lamella

Figs 14, 15. Empis (Anacrostichus) pallida Loew, 1861 , male: 14 — postabdomen, lateral view; 15 — hypopygium, lateral view (setation omitted). Abbreviations: cerc — cercus; ej apod — ejaculatory apodeme; epand — epandrium; goncx apod — gonocoxal apodeme; hypd — hypandrium; ph — phallus; T — tergite; S — sternite. Scale bar is 0.1 mm.

Рис. 14, 15. Empis (Anacrostichus) pallida Loew, 1861 , самец: 14 — постабдомен, вид сбоку; 15 — гипопигий, вид сбоку (Щетинки не укаЗаны). СокраЩениЯ: cerc — церк; ej apod — ЭЯкулЯторнаЯ аподема; epand — Эпандрий; goncx apod — гонококсальнаЯ аподема; hypd — гипандрий; ph — фаллус; T — тергит; S — стернит. Масштаб 0,1 мм.

340 Nearctic species of the empidid subgenus Anacrostichus rather subtriangular (Fig. 15), apex more or less rounded; with moderately long setae more numerous along lower margin. Hypandrium reduced, very narrow, subrectangular viewed laterally, broadly attached to epandrial lamella, fused with base of phallus, bare; gonocoxal apodeme large, subovate, extending slightly beyond middle of ejaculatory apodeme. Subepandrial sclerite broadly divided medially into two bacilliform sclerites. Cerci separated with each other, partly fused to epandrial lamella; cercus very deeply concave dorsally forming two narrowly connected lobes (lateral view); anterior cercal lobe very narrow, bacilliform; posterior cercal lobe fused to epandrial lamella, broader than anterior lobe, elongate oval viewed laterally, with apex somewhat upturned. Hypoproct weakly sclerotised, bare. Phallus moderately long, gently arched; thickened on about basal third (lateral view), slender on remaining portion (thickened portion well visible in situ). Ejaculatory apodeme large, extended far beyond basal curvature of phallus, with small lateral wings.

Female. Unknown.

REMARKS. Empis pallida is the only described species of Anacrostichus with yellow body. Melander [1928] placed E. pallida in the subgenus Xanthempis . Indeed, this species resembles E. scutellata Curtis, 1835 . The habitus of E. pallida is the same as Empis (Anacrostichus) sp. 1 (Figs 44, 45).

DISTRIBUTION. Canada (Ontario). USA (Massachusetts, New Hampshire, New York, Vermont) .