Tachytrechus peruicus Ya

Brooks, Scott E. & Cumming, Jeffrey M., 2008, The Tachytrechus alatus species group (= Syntomoneurum Becker) revisited: new species and revised species group limits (Diptera: Dolichopodidae), Zootaxa 1676, pp. 1-27 : 14-17

publication ID	https://doi.org/ 10.5281/zenodo.180314
DOI	https://doi.org/10.5281/zenodo.6227309
persistent identifier	https://treatment.plazi.org/id/03D787A6-FFAC-FF83-E1C9-63DAFA9EFC06
treatment provided by	Plazi
scientific name	Tachytrechus peruicus Ya
status

Treatment

Tachytrechus peruicus Ya View in CoL ng & Z h a n g

(Figs. 7, 13)

Syntomoneurum beckeri Parent 1931: 17 .

Syntormoneurum beckeri View in CoL , misspelling by Parent 1931: 17.

Tachytrechus beckeri (Parent) : Brooks (2005).

Tachytrechus peruicus Yang & Zhang View in CoL in Yang et al. (2006); replacement name for Tachytrechus beckeri ( Parent) 1931 View in CoL ; preoccupied by Tachytrechus beckeri Lichtwardt, 1917 View in CoL .

Diagnosis. Body length 5.3–5.4 mm; wing length 5.3–5.5 mm; face brownish with weak silvery-green reflections; male clypeus rounded below; 1 notopleural bristle; male fore tarsus distinctly silvery anteriorly, basitarsus lacking curved ventral setae, tarsomeres 3 and 4 flattened; hind femur mainly yellow with 1 anterior preapical bristle; bends in M distinct, obtuse; R4+5 and M subparallel distally (Figs. 7A, 7B); male wing (Fig. 7A) without costal swelling, with M and CuA1 thickened in basal section; male tergite 5 with posterior FIGURE 6. Tachytrechus giganteus (Brooks) : (A) male wing; (B) female wing; (C) male clypeus; (D) hypandrium (ventral view); (E) hypopygium (left lateral view). Adapted from Brooks & Wheeler (2002). Abbreviations: A1: anal vein; apv lobe: apicoventral epandrial lobe; bv lobe: basiventral epandrial lobe; cerc: cercus; CuA1: 1st anterior branch of cubital vein; dm-cu: discal medial-cubital crossvein; hypd: hypandrium; M: medial vein; ph: phallus R1: 1 radial vein; R2+3: 2nd + 3rd radial vein; R4+5: 4th + 5th radial vein.

FIGURE 7. Tachytrechus peruicus Yang & Zhang : (A) male wing; (B) female wing; (C) hypandrium (ventral view); (D) hypopygium (left lateral view). Figure D adapted from Brooks & Wheeler (2002). Abbreviations: A1: anal vein; apv lobe: apicoventral epandrial lobe; bv lobe: basiventral epandrial lobe; cerc: cercus; CuA1: 1st anterior branch of cubital vein; dm-cu: discal medial-cubital crossvein; hypd: hypandrium; M: medial vein; pgt: postgonite; ph: phallus; R1: 1st radial vein; R2+3: 2nd + 3rd radial vein; R4+5: 4th + 5th radial vein; vsur: ventral lobe of surstylus.

membraneous region bordering and mostly confined to dorsal portion of sclerite (cf. Fig 9 View FIGURE 9 A); hypopygium (Figs. 7C, 7D): right and left basiventral epandrial lobes digitiform, right lobe longer; apicoventral epandrial lobe elongate, projected ventrally, with blunt, expanded apex bearing medial and outer setae; accessory epandrial process absent; apicolateral arm of postgonite with medial process present, with long hook-like process apically; cercus subrectangular in dorsal view, longer than wide, apical and lateral margin darkened; hypandrium narrow and symmetrical in ventral view; ventral surstylar lobe with series of parallel diagonal ridges on ventral surface; dorsal lobe about half as long as ventral lobe; phallus with fin-like projection before middle. Female sternite 8 divided medially, lacking deep medial invagination.

Type material examined. Holotype Ψ, PERU: Cusco, Rio Urubamba, Umahuankilia, 500 m, 13.xi.1903, C.A.W. Schnuse ( SMTD).

Other material examined. 1ɗ and 1Ψ, PERU: “?rég. côtière du N.” ( MNHN).

Distribution. Tachytrechus peruicus is known from the type locality near the Rio Urubamba in southeastern Peru, and from two specimens collected in the northern costal region of Peru ( Fig. 13 View FIGURE 13 ); however the precise location of the latter locality is unknown and has been approximated on Fig. 13 View FIGURE 13 (indicated with a “?”).

Remarks. Yang and Zhang in Yang et al. (2006) proposed the name T. peruicus for T. beckeri ( Parent) 1931 in order to remove the homonymy with older name T. beckeri Lichtwardt 1917 , which resulted from the synonymy of Syntomoneurum with Tachytrechus by Brooks (2005). The eversible glandular structure present in the other species was not found in the single male specimen of T. peruicus . However, the abdomen of this specimen was partially damaged prior to our examination and dissection, and the eversible gland, if present, may have been lost as a result.