Iteaphila, Zetterstedt

Sinclair, Bradley J. & Shamshev, Igor V., 2021, World revision of Iteaphila with unbranched radial vein (Diptera: Empidoidea: Iteaphilidae), Zootaxa 4968 (1), pp. 1-89 : 81-86

Key to Iteaphila with unbranched radial vein (R 4+5) from the Nearctic Region

1 Acrostichals biserial; if doubtful, then males with very broad epandrium dorsal bridge ( Fig. 21 )....................... 2

- Acrostichals 4-serial (at least anteriorly), often arranged in widely separated paired rows; epandrium with narrow dorsal bridge............................................................................................. 18

2 Anepisternum and anepimeron mostly bare and shiny; male terminalia subrectangular, greatly extended horizontally, longer than final three abdominal segments; epandrium expanded apically ( Sinclair & Shamshev, 2012, fig. 8B).................................................................................................. I. nitidula Zetterstedt

- Anepisternum and anepimeron finely pollinose; male terminalia subtriangular, not extended horizontally, much shorter than final three abdominal segments; epandrium more or less pointed apically......................................... 3

3 Male ............................................................................................... 4

- Female [unknown for I. falcata , I. lolo sp. nov., I. stentor ].................................................... 16

4 Epandrium oval, with broad dorsal bridge connecting lamellae and narrow upright surstylus; hypandrium clothed in spiny projections ( Figs 21–23 )................................................................................ 5

- Epandrium prolonged posteriorly, with narrow dorsal bridge and horizontal, hook-like surstylus; hypandrium without spiny projections ( Figs 55 , 61 )................................................................................ 7

5 Base of postpedicel not distinctly expanded; only cercus and surstylus extending beyond margin of epandrium ( Fig. 21 )...................................................................................... I. beringiensis sp. nov.

- Base of postpedicel distinctly expanded; phallus, cercus and surstylus extending beyond margin of epandrium ( Figs 22, 23 ). 6

6 Phallus arising from epandrium, separate from cerci ( Fig. 23 )...................................... I. recta sp. nov.

- Phallus arising from epandrium as pair of narrow projections between cerci ( Fig. 22 ).................. I. bifida sp. nov.

7 Phallus with broad cup-like or funnel-like apex ( Figs 77, 78 )................................................... 8

- Phallus with slender apex, not divergent or expanded apically ( Figs 55 , 61 )....................................... 9

8 Apex of phallus cup-shaped, nearly symmetrical ( Fig. 78 )..................................... I. stentor (Melander)

- Apex of phallus funnel-shaped, prolonged anteriorly ( Fig. 77 )................................. I. parastentor sp. nov.

9 Surstylus narrow, upright, parallel to phallus ( Fig. 61 )......................................... I. miranda sp. nov.

- Surstylus short, inconspicuous, usually projecting little beyond epandrium....................................... 10

10 Hypoproct process long and narrow, nearly as long as or longer than cercus ( Fig. 55 )............................... 11

- Hypoproct process short and narrow, shorter than cercus or inconspicuous ( Fig. 47 )................................ 12

11 Abdomen with pale setae; phallus long and slender, filament-like; cercus short, with longer hypoproct process ( Fig. 55 )........................................................................................ I. sierrensis sp. nov.

- Abdomen with dark setae; phallus with asymmetrical apex, arched to left; cercus elongate, more than half length of epandrium, with shorter hypoproct process ( Sinclair & Shamshev 2012, fig. 6A)............................... I. falcata Sinclair

12 Setae of scutellum yellow................................................................... A. lolo sp. nov.

- Setae of scutellum dark............................................................................... 13

13 Postpedicel distinctly broader than distance between posterior ocelli (eastern North America)........................ 14

- Postpedicel narrower, subequal to distance between posterior ocelli (eastern and western North America).............. 15

14 Phallus slender and filamentous with long membranous tip; apex of hypandrium deeply notched; phallic guide not extending beyond hypandrium ( Fig. 36 )......................................................... I. longiphallus sp. nov.

- Phallus heavily sclerotized with recurved, hooked apex; apex of hypandrium without notch; phallic guide extending well beyond hypandrium, associated with apex of phallus ( Fig. 69 ).................................. I. recurvata sp. nov.

15 Phallus strongly arched at apex and tapered to narrow point; anterior projection at mid-length of phallus; apex of hypandrium not divided into pair of rounded projections ( Fig. 68 )....................................... I. polygyna (Melander)

- Phallus straight preapically, apex strongly recurved with broad apex; without anterior projection at mid-length of phallus ( Fig. 67 ); apex of hypandrium divided into pair of rounded projections ( Fig. 66 )..................... I. oedalina (Zetterstedt)

16 Scutum dorsally largely shiny, with pruinescence on postpronotal lobes and area posterior, notopleuron and prescutellar depression........................................................................... I. sierrensis sp. nov.

- Scutum largely with distinct pruinescence [difficult to confidently distinguish without associated males]............... 17

17 Femora and coxae yellow................................................................................... ( I. longiphallus sp. nov., I. miranda sp. nov., I. oedalina (Zetterstedt) [in part], I. polygyna (Melander) , I. recurvata sp. nov.)

- Femora and coxae dark, at most knew pale....................................................................... ( I. beringiensis sp. nov., I. bifida sp. nov., I. oedalina (Zetterstedt) [in part], I. recta sp. nov., I. parastentor sp. nov.)

18 Setae of scutellum yellow.............................................................................. 19

- Setae of scutellum black............................................................................... 20

19 Scutum with thin pruinescence; apical bend of phallus and phallic guide long and slender with pointed apex ( Fig. 43 ); halteres yellow; females entirely yellow, except for head and often scutum with darkened median stripe ( Figs 14 , 15 ).............................................................................................. I. flavipilosa (Melander)

- Scutum dark and shiny, with pruinescence anteriorly and on prescutellar depression; apical bend of phallus and phallic guide shorter, broader, with apex of phallus truncate ( Fig. 44 ); halteres brown; females dark.............. I. glabricula sp. nov.

20 Male .............................................................................................. 21

- Female [unknown for I. arnaudi , I. grandis ]............................................................... 28

21 Ejaculatory apodeme greatly enlarged, twice length of gonocoxal apodeme ( Fig. 41 ), distorting apex of abdomen in dried specimens............................................................................. I. brooksi sp. nov.

- Ejaculatory apodeme not twice length of gonocoxal apodeme................................................. 22

22 Epandrium with very broad dorsal bridge connecting lamellae; ventral margin of epandrium with deep notch; phallus straight apically, with short hook at apex ( Fig. 24 )................................................... I. tribulosa sp. nov.

- Epandrium with narrow dorsal bridge connecting lamellae; ventral margin of epandrium evenly curved, without notch; phallus strongly curved apically, without short hook at apex ( Figs 46, 48 ).............................................. 23

23 Hypoproct process long and narrow, extending beyond apex of cercus; apex of epandrium with strongly, dorsally produced surstylus ( Figs 46, 48 )................................................................................ 24

- Hypoproct process short and narrow, much shorter than length of cercus; apex of epandrium without strongly, dorsally produced surstylus ( Fig. 58 ).................................................................................... 25

24 Wing length less than 4.0 mm; surstylus narrow and slightly sinuous; phallic guide rounded apically, not expanded ( Fig. 48 )................................................................................ I. longipalpis (Melander)

- Wing length greater than 4.0 mm; surstylus broad and rounded apically; phallic guide expanded apically ( Fig. 46 ).............................................................................................. I. grandis sp. nov.

25 Apex of hypandrium narrow, without short spiny projections.................................................. 26

- Apex of hypandrium broad, with short spiny projections ( Fig. 39 ).............................................. 27

26 Postgonite distant from dorsal margin of epandrium; surstylus projecting horizontally ( Fig. 58 )....... I. subnupta sp. nov.

- Postgonite extending to near dorsal margin of epandrium; surstylus projecting dorsally ( Fig. 37 )........ I. arnaudi sp. nov.

27 Postsutural supra-alar region with pruinescence; surstylus very short, only slightly emerging above epandrium; hypandrium expanded at apex in posterior view ( Fig. 38 )................................................. I. bayarea sp. nov.

- Postsutural supra-alar region shiny without pruinescence; surstylus projecting dorsally well beyond epandrium; dorsal phallic process long, projecting from epandrium; hypandrium tapered in posterior view ( Fig. 54 )............. I. nupta (Melander)

28 Base of postpedicel distinctly expanded; palpi robust, not filamentous............................ I. tribulosa sp. nov.

- Base of postpedicel not distinctly expanded; palpi usually very slender, filamentous (difficult to confidently distinguish females without associated males).............................................................................. 29

29 Halteres with pale knob............................................................ I. longipalpis (Melander)

- Halteres with dark knob............................................................................... 30

30 Sides of posterior scutum shiny lateral to dorsocentral row (viewed anteriorly)...................... I. bayarea sp. nov.

- Sides of posterior scutum with pruinescence lateral to dorsocentral row (viewed anteriorly)............................................................................. I. brooksi sp. nov., I. nupta (Melander) , I. subnupta sp. nov.

Feeding habits

As briefly reviewed by Sinclair & Shamshev (2012), adults of Iteaphila are flower visitors. In addition to a number of Iteaphila species (i.e., radial vein forked), Downes (unpubl. data) also examined a female specimen of “ Anthepiscopus ” (i.e., radial vein unforked), collected in Mt. Rainier National Park ( USA: Washington). As outlined in Sinclair & Shamshev (2012), Downes also observed a fully expanded crop with a few pollen grains in this specimen. Although Downes thought males were only nectar feeders ( Sinclair & Shamshev 2012), we have observed pollen grains in dissected and cleared male abdomens of a number of species. The flowers upon which Iteaphila with unbranched R 4+5 have been collected are listed in Table 4 .

DNA barcode sequence data

The COI barcode data for Nearctic Iteaphila with branched and unbranched R 4+5 are summarized in the neighbourjoining tree ( Fig. 82 ). DNA data for this project was obtained for two purposes. Firstly, sequenced females which clustered with sequenced males permitted confirmation of identification. These associated females were carefully examined for species specific characters for identification and description. Secondly, the use of sequences permitted recognition of possible cryptic species complexes.

Among the 36 known Nearctic species of Iteaphila , barcode data for 18 named species and four un-named species were available. Palaearctic specimens with associated barcode data were not available for study. Two species of Iteaphila with unbranched R 4+5 were unidentified due to absence of associated males, one of which is likely nupta / subnupta based on distribution, outcome in the key and barcode coverage of other Nearctic species. A female specimen from Nome, Alaska (103409), originally identified as I. bulbosa , appears to represent a currently unrecognized species. In addition, a specimen (103384) originally identified as I. orchestris needs to be re-evaluated and likely represents a new species.

Iteaphila nitidula has very unique male terminalia (elongate epandrium and looping phallus) ( Fig. 7 ) and was originally believed to be a widespread Holarctic species. On the basis of COI barcode data, this species appears to comprise possibly as many as six cryptic species (including public data available on the BOLD website) and specimens across its range will need to be investigated for additional and currently unrecognized species. Differences in the inner shape of the epandrium and medial projection may indicate different species. The Nearctic specimens listed here were assigned to different BINs, none of which match I. nitidula from near the type locality in Sweden (BIN ID: ACD3033) . In contrast, Nearctic specimens of I. macquarti , another widespread Holarctic species, are all assigned to the same BIN (AAL8966), the same as specimens from near the type locality in Norway .

Figures

FIGURE 82. Neighbour-joining tree of 79 specimens of Iteaphila with COI sequences, including unique voucher number (all from this study, except numbers starting with BIOUG), sequence length and GenBank accession number.

FIGURES 21–25. Male terminalia of Iteaphila with unbranched R 4+5. 21, I. beringiensis sp. nov., lateral view; 22, I. bifida sp. nov., lateral view, with arrow indicating apex of phallus in posterior view; 23, I. recta sp. nov., lateral view; 24, I. tribulosa sp. nov., lateral view; 25, same, apex of hypandrium, posterior view. Scale bar = 0.1 mm. Abbreviations: cerc—cercus; epand— epandrium; epand brg—epandrial bridge; hypd—hypandrium; ph—phallus; sur—surstylus.

FIGURES 53–57. Male terminalia of Iteaphila with unbranched R 4+5. 53, I. luteitibia sp. nov., lateral view; 54, I. nupta (Melander), lateral view; 55, I. sierrensis sp. nov., lateral view; 56, I. spinosa sp. nov., lateral view; 57, same, left cercus, dorsal view. Scale bar = 0.1 mm. Abbreviations: cerc—cercus; hypd—hypandrium; hyprct proc—hypoproct process; ph—phallus; ph gd—phallic guide; sur—surstylus.

FIGURES 58–61. Male terminalia of Iteaphila with unbranched R, lateral view. 58, I. subnupta sp. nov.; 59, I. aktruensis 4+5 sp. nov.; 60, I. incus sp. nov.; 61, I. miranda sp. nov. Scale bar = 0.1 mm. Abbreviations: pgt—postgonite; ph—phallus; sur—surstylus.

FIGURES 75–78. Male terminalia of Iteaphila with unbranched R 4+5. 75, I. zontaki (Nowicki), lateral view; 76, same, phallus, dorsal view; 77, I. parastentor sp. nov., lateral view; 78, I. stentor (Melander), lateral view. Scale bar = 0.1 mm. Abbreviations: ph—phallus; sur—surstylus.

FIGURES 45–48. Male terminalia of Iteaphila with unbranched R, lateral view. 45, I. gracilis sp. nov.; 46, I. grandis sp. 4+5 nov.; 47, I. lolo sp. nov.; 48, I. longipalpis (Melander). Scale bar = 0.1 mm. Abbreviations: cerc—cercus; epand brg—epandrial bridge; hyprct proc—hypoproct process; ph—phallus; ph gd—phallic guide; sur—surstylus.

FIGURES 36–40. Male terminalia of Iteaphila with unbranched R 4+5, lateral view. 36, I. longiphallus sp. nov.; 37, I. arnaudi sp. nov.; 38, I. bayarea sp. nov.; 39, same, apex of hypandrium, posterior view; 40, Iteaphila sp., apex of hypandrium, posterior view. Scale bar = 0.1 mm. Abbreviations: pgt—postgonite; ph—phallus; ph gd—phallic guide; sur—surstylus.

FIGURES 66–70. Male terminalia of Iteaphila with unbranched R. 66, I. oedalina (Zetterstedt), posterior view; 67, same, 4+5 lateral view; 68, I. polygyna (Melander), lateral view; 69, I. recurvata sp. nov., lateral view; 70, I. sakhalinensis sp. nov., lateral view. Scale bar = 0.1 mm. Abbreviations: pgt—postgonite; ph—phallus; sur—surstylus.

FIGURES 41–44. Male terminalia of Iteaphila with unbranched R 4+5, lateral view. 41, I. brooksi sp. nov.; 42, I. dichoptica sp. nov.; 43, I. flavipilosa (Coquillett); 44, I. glabricula sp. nov. Scale bar = 0.1 mm.Abbreviations: ej apod—ejaculatory apodeme; goncx apod—gonocoxal apodeme; pgt—postgonite; ph—phallus; ph gd—phallic guide.

FIGURES 11–14. Species of Iteaphila with unbranched R 4+5. 11, I. beringiensis sp. nov., male, lateral view, scale bar = 1 mm; 12, I. bartaki sp. nov., male, lateral view, scale bar = 1 mm; 13, I. dichoptica sp. nov., male holotype, lateral view, scale bar = 0.5 mm; 14, I. flavipilosa, female, dorsal view, lateral view, scale bar = 0.5 mm.

FIGURES 15–18. Species of Iteaphila with unbranched R, lateral view. 15, I. flavipilosa, female, lateral view; 16, I. 4+5 flavipilosa, male, lateral view; 17, I. glabricula sp. nov., male; 18, I. grandis sp. nov., male. Scale bar = 1 mm.

FIGURES 5–7. Species of Iteaphila with unbranched and branched R 4+5, lateral view. 5, I. oedalina, male; 6, I. oedalina, male; 7, I. nitidula, male. Scale bar = 1 mm. Abbreviations: R4—upper branch of third branch of radius; R 5 —lower branch of third branch of radius; R —third branch of radius.

Tables

TABLE 4. List of flowers visited by Iteaphila with unbranched R 4+5

Taxon	Plant family	Common name	Iteaphila species	Reference
Coptis aspleniifolia Salisb.	Ranunculaceae	fern-leaf goldthread	I. recta	Present study (label data); Willson & Anderson (2007)
Cornus sericea L.	Cornaceae	red osier dogwood	I. flavipilosa	Present study (label data)
Erythronium montanum S.Wats.	Liliaceae	avalanche lily	I. longipalpis	Present study (label data)
Heracleum sp.	Apiaceae	cow parsnip	I. flavipilosa	Present study (label data)
Ledum groenlandicum Oeder	Ericaceae	bog labrador tea	I. longipalpis , I. mi- randa, I. recta	Present study (label data)
Ligusticum grayi (J.M.Coult.) Rose	Apiaceae	Gray’s licorice-root	I. sierrensis	Present study (label data)
Linum lewisii Pursh.	Linaceae	Lewis flax	“ Anthepiscopus ” sp.	Kearns & Inouye (1994)
Lomatium orogenioides (J.M.Coult. & Rose) Mathias [= L. tenuissi- mum (Geyer ex Hook.)]	Apiaceae	biscuitroot	I. polygyna	Present study (label data)
Oxalis sp.	Oxalidaceae	wood sorrels	I. bartaki	Present study (label data)
Petasites albus (L.) Gaertn.	Asteraceae	white butterbur	I. bartaki	Present study (label data)
Platanthera stricta Lindley	Orchidoideae	slender bog orchid	I. longipalpis	Patt et al. (1989)
Prunus virginiana L.	Rosaceae	chokecherry	I. glabricula , I. recta	Present study (label data)
Ribes alpinum L.	Grossulariaceae	alpine current	I. ribesii	Becker (1891)
Ribes montigenum Mc- Clatchie	Grossulariaceae	gooseberry	I. bifida	Present study (label data)
Ribes sp.	Grossulariaceae	gooseberry	I. nupta , I. recurvata	Present study (label data)
Salix spp.	Salicaceae	willow	I. beringensis , I. bifida , I. oedalina , I. polygyna	Present study (label data); Tuomikoski (1952)
Shepherdia canadensis (L.) Nutt.	Elaeagnaceae	Canada buffaloberry	I. oedalina	Present study (label data
Shepherdia sp.	Elaeagnaceae	buffaloberry	I. bifida	Present study (label data; Fig. 2)