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 : 8-9

Iteaphila Zetterstedt

( Figs 1–3 , 5–9 , 11–18 )

Iteophila Zetterstedt, 1837: 31 , nomen nudum.

Iteaphila Zetterstedt, 1838: 540 . Type species: Iteaphila macquarti Zetterstedt, 1838 (des. Coquillett, 1903: 251).

Steleocheta Becker, 1887: 129 . Type species: Steleocheta setacea Becker, 1887 (by monotypy) (= Iteaphila macquarti Zetterstedt, 1838 ).

Stelochaeta or Steleochaeta , errors: Chvála & Wagner, 1989: 230.

Anthepiscopus Becker, 1891: 281 . Type species: Anthepiscopus ribesii Becker, 1891 (des. Coquillett, 1903: 246), syn. nov.

Diagnosis. Iteaphila is newly defined and distinguished by the following combination of characters: postpedicel elongate and nearly parallel-sided;stylus usually short and quadrate, one-articled with distinct apical mechanoreceptor (sensillum); proboscis generally elongate and obliquely projecting; labrum generally elongate, without epipharyngeal blades; palpi elongate and parallel with labrum; prosternum isolated, not fused to proepisternum; scutellum with more than 3 pairs of apical setae; laterotergite bare; male legs unmodified; basal costal seta absent; R 4+5 branched or unbranched; cell dm usually truncate apically; male terminalia usually with hypoproct process; closely approximated postgonites; inner apodeme and phallic guide present; surstylus hook-like; without epandrial lobe.

Remarks. The monophyly of the genera Iteaphila and Anthepiscopus with respect to each other has long been questioned. The genera are only distinguishable on the basis of the radial branching and if the wings are lost, generic assignment is difficult. It became clear in this third study on the group, that male genitalic characters grouped species from both genera and occasionally the form of R 4+5 was variable within species. In addition, the cladistic analyses discussed above resulted in grouping species from both genera and clearly indicate that the genera are not monophyletic with respect to each other. We believe that these observations and analyses justify combining these genera and the proposal that Anthepiscopus is a junior synonym of Iteaphila .

The above definition more clearly defines and distinguishes the genus Iteaphila and excludes the species of the Iteaphila setosa species group ( Figs 4 , 10 ). These species are here transferred to a new genus diagnosed below.

Iteaphila is exclusively a Holarctic genus and the Chilean species, Anthepiscopus extimus Collin, 1933 is not congeneric. This species is conspecific with “new genus 2”, originally thought to be related to Iteaphila because of the angle of the proboscis and flower visiting habits ( Sinclair & Cumming 2000) and is presently tentatively assigned to the Empidinae (Rafael et al., in prep.). This undescribed genus is characterized also by both branched and unbranched R 4+5 species, complete precoxal bridge, arched palpi, epipharyngeal blades present, slender stylus, row of long, erect setae at base of prementum, upright epandrium without dorsal bridge, long slender phallus, hypoproct not produced into processes and postgonites present.

Genitalic homologies. The revision of this group of species enabled us to confirm the genitalic homologies of the processes arising from near the base of the phallus, associated lateral apodemes (especially enlarged in nupta group) and paired flanking processes. The confusion was created by the posterior displacement of where the phallus and hypandrium come together. The phallus articulates with a narrow bridge from which the paired, closely approximated median postgonites arch dorsally ( Figs 37 , 58 ). Also associated with the bridge are paired inner apodemes between the ejaculatory and gonocoxal apodemes ( Fig. 29 , i apod). The paired processes flanking the phallus are termed the phallic guide ( Figs 32 , 53 ) and appear to be associated with an apical invagination of the hypandrium which arches anteriorly beneath the phallus and guide as far as the base of the phallic guide, but this region is mostly membranous and it is difficult to follow connections.

Figures

FIGURES 1–4. Photographs of living species of Paraiteaphila and Iteaphila with unbranched R 4+5. 1, Iteaphila sp., female, lateral view, Hoh River, Washington, USA (photograph @ S. Marshall); 2, I. bifida sp. nov., lateral view, male on Shepherdia flowers, British Columbia, Canada (photograph @ A. Borkent); 3, Iteaphila sp., oblique dorsal view, Mt. Washington, New Hampshire, USA (photograph @ T. Murray); 4, Paraiteaphila italica (Loew), near Pizzo Camarda (AQ), Italy, 42°27′22.2″N 13°27′07.7″E (photograph @ E. Santarelli).

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.

FIGURES 8–10. Species of Paraiteaphila and Iteaphila with unbranched R 4+5, lateral view. 8, I. longipalpis, male, scale bar = 1 mm; 9, I. parastentor, male, scale bar = 0.5 mm; 10, Paraiteaphila sp., female, scale bar = 0.75 mm.

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 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 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 29–32. Male terminalia of Iteaphila with unbranched R 4+5, lateral view. 29, I. bartaki sp. nov.; 30, I. falki sp. nov.; 31, I. kyrgyzstanensis sp. nov.; 32, I. ribesii (Becker). Scale bar = 0.1 mm. Abbreviations: cerc—cercus; ej apod—ejaculatory apodeme; goncx apod—gonocoxal apodeme; hypd—hypandrium; hyprct proc—hypoproct process; i apod—inner apodeme; ph—phallus; ph gd—phallic guide; 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.