Pseudosympycnus robinsoni, Soares & Capellari, 2020

Soares, Matheus M. M. & Capellari, Renato S., 2020, Review of the Neotropical genus Pseudosympycnus (Diptera: Dolichopodidae) with description of six new species from Brazil and Peru, Zootaxa 4881 (2), pp. 231-256 : 249-250

Pseudosympycnus robinsoni sp. nov.

( Figs 9 , 15 , 36, 37 , 60, 61 , 71 , 86 )

Diagnosis (male). Metepimeron yellow ( Fig. 9 ). Femora entirely yellow ( Fig. 9 ). Tibia I not compressed. Tarsus I ( Fig. 60 ) brown, except It 1 yellow; It 1 with 4 anterodorsal and 3 long ventral setae near apex; It 2 with 4 anterior setae curved downwards and increasing in size towards apex, with 2 dorsal bristles at apex; It 3–4 laterally flattened, with indistinct rows of dorsal to anteroventral setae; It 5 with row of anterior and anterodorsal setae. Tarsus II unmodified. Tarsus III ( Fig. 61 ): IIIt 3–5 with anterior and anteroventral rows of long setae, slightly curved at apex.

Description. Male ( Fig. 9 ). (holotype apparently dull colored due to long term storage in alcohol). Body length [holotype]: 3.0 mm. Wing length: 2.8 mm, width; 0.8 mm. Head ( Figs 36, 37 ). Similar to P. araza sp. nov., except as noted. Face narrowing in middle, narrower than mid ocellus. Frons dark brown with some violet reflections and covered by weak pruinosity. Occiput dark metallic green with silvery reflections and pale hairs below; one pair of postocellar very small. Palpus ( Fig. 15 ) thin, ovoid, slightly longer than wide, 1/3 as long as head height, yellow with weak silvery pruinosity, covered only with few short, white hairs. Antenna entirely pale brown. Thorax. Similar to P. araza sp. nov., including metepimeron and dorsal part of metepisternum dark yellow. Mesonotum and scutellum mostly pale brown colored with greenish and violet reflections. Pleura pale brown with some bluish reflections and little pruinosity, but metepimeron and dorsal part of metepisternum (around posterior spiracle) yellow. Scutellum with a few scattered short pale hairs. Legs. Legs yellow, except It 2–5, lateral surface of coxa II, apex of IIt 1, IIt 2–5 and entire tarsus III brown. Leg I. Podomere ratios: 20, 18, 11, 2, 7, 8, 4. Anterior surface of coxa I covered by short brownish setae, outer edge with 3 anteromedial longer black setae. Femur I with short vestiture of black setae, except ventral surface bare, with 2 conspicuous posteroventral setae near basal 1/4, almost as long half of femur length and curved at apex (MSSC); with 1 short posteroventral seta and 2 short anteroventral setae near apex. Tibia I with dorsal row of short setae at apical 3/4, with 4 posterodorsal short setae at 2/7, 3/7, 4/7, 6/7, with 1 anterior, 1 anteroventral and 1 posteroventral seta at apex, anterior one as long as 1/3 of It1 (MSSC). Tarsus I ( Fig. 60 ): It 1 overlapping half of posterior surface of It 2, with 4 anterodorsal and 3 long ventral setae near apex; It 2 with 4 anterior setae curved downwards and increasing in size towards apex, with 2 dorsal bristles at apex; It 3–4 laterally flattened, with indistinct rows of dorsal to anteroventral setae; It 4 slightly narrowing towards apex; It 5 with row of anterior and anterodorsal setae as long as the tarsomere (all MSSC). Leg II. Podomere ratios: 24, 28, 21, 10, 7, 5, 3. Anterior surface of coxa II covered by long setae, 2–3 stronger along apical edge, and 3–4 stronger on posterolateral margin. Femur II covered by short black vestiture, except bare ventral surface, with 1 anteroventral and 1 posteroventral pre-apical seta. Tibia II with 4 anterodorsal setae at 1/7, 3/7, 5/7, 7/7, with 2 dorsal setae at 1/7, 3/7, with 1 posterodorsal, 1 anteroventral and 1 posteroventral seta at apex. Leg III. Podomere ratios: 26, 31, 3, 14, 6, 5, 3. Coxa III with 1 long seta as long as coxa at basal 1/3 and 1 smaller at apex. Femur III with short vestiture, bare on ventral surface; with ventral row of 3 setae on basal half, basal 2 short and curved at apex, apical one longer, twice diameter of femur at broadest point (MSSC) ( Fig. 71 ); with 1 anterior pre-apical. Tibia III with 4 anterodorsal setae at 1/7, 3/7, 5/7 and 7/7, with row of dorsal setae as long as diameter of tibia. Tarsus III ( Fig. 61 ): IIIt 3–5 with posterior and posteroventral rows of long setae that are slightly curved at apex (MSSC). Wing. Similar to P. araza sp. nov. (see above). Abdomen. Setation and general color pattern similar to P. araza sp. nov., but mostly brown with only coppery reflections, including brown tergite 1, lateral yellow patches on tergites 2–3 smaller, sternites 1–3 yellow, 4–5 brown. Hypopygium. Not dissected, capsule and surstylus brown, cercus yellowish.

Female. Unknown.

Type material. HOLOTYPE Ƌ, labelled: “ BRASIL, Acre, Mâncio / Lima, Pq [ Parque ] Nac [ Nacional ] Serra do / Divisor , Malaise / 5.x.2007, L. Menezes ”, “ HOLOTYPE / Pseudosympycnus robinsoni / Soares & Capellari” [red label] ( INPA) . Holotype in good condition, terminalia not dissected.

Etymology. Named after Harold Robinson (NMNH), for his contribution to the knowledge of the genus Pseudosympycnus .

Remarks. The new species is superficially similar to P. albipalpus by the metepimeron yellow, It 2 with 2 dorsal bristles at apex, and IIIt 3–5 with posterior and posteroventral rows of long setae that are slightly curved at apex. Nevertheless, P. robinsoni sp. nov. can be separated by the It 3 being shorter than It 4 and laterally flattened (It 3 twice the length of It 4 and cylindrical in P. albipalpus ) and femur III with ventral row of 3 setae on basal half (bare in P. albipalpus ). Since the male hypopygium would not offer useful characters for ready identification, we preferred to not dissect the holotype to avoid damaging the single known specimen.

Distribution. Brazil (State of Acre) ( Fig. 86 ).

Figures

FIGURE 86. Known geographic distribution of species of Pseudosympycnus Robinson.

FIGURES 7–11. Pseudosympycnus Robinson. Habitus. 7. P. palpiger (Van Duzee, 1931), paratype Ƌ; 8. P. perornatus Robinson, 1967, paratype Ƌ; 9. P. robinsoni sp. nov., holotype Ƌ; 10. P. sehnali sp. nov., holotype Ƌ; 11. P. singularis (Parent, 1934), syntype Ƌ (photo: Erica McAlister). Scale bars = 1 mm.

FIGURES 12–15. Pseudosympycnus Robinson. Male palpus under scanning electron microscopy. 12. P. bickeli sp. nov., holotype Ƌ; 13. P. latitibia sp. nov., paratype Ƌ; 14. P. palpiger (Van Duzee, 1931), paratype Ƌ; 15. P. robinsoni sp. nov., holotype Ƌ. Scale bars = 0.1 mm. Photogaphs: L.C. Dias.

FIGURES 30–39. Pseudosympycnus Robinson. Head. 30–32. P. palpiger (Van Duzee, 1931). 30–31. Paratype Ƌ. 30. Anterior view. 31. Lateral view. 32. Paratype ♀, anterior view. 33–35. P. perornatus Robinson, 1967. 33–34. Paratype Ƌ. 33. Anterior view. 34. Lateral view. 35. Paratype ♀, anterior view; 36–37. P. robinsoni sp. nov., holotype Ƌ. 36. Anterior view. 37. Lateral view; 38–39. P. sehnali sp. nov., holotype Ƌ. 38. Anterior view. 39. Lateral view. Scale bars = 0.2 mm.

FIGURES 55–65. Pseudosympycnus Robinson. Male tarsus I and III. 55–57 P. palpiger (Van Duzee, 1931). 55, 57. Paratype Ƌ. 55. Tarsus I. 57. Tarsus III. 56. Identified specimen from Acre, Brazil, tarsus I. 58–59. P. perornatus Robinson, 1967, paratype Ƌ. 58. Tarsus I. 59. Tarsus III; 60–61. P. robinsoni sp. nov., holotype Ƌ. 60. Tarsus I. 61. Tarsus III; 62–63. P. sehnali sp. nov., holotype Ƌ. 62. Tarsus I. 63. Tarsus III; 64–65. P. singularis (Parent, 1934), syntype Ƌ (photo: Erica McAlister). 64. Tarsus I. 65. Tarsus III. Scale bars = 0.2 mm.

FIGURES 66–71. Pseudosympycnus Robinson. Male secondary sexual characters. 66. P. araza sp. nov., paratype Ƌ, femur and tibia I; 67. P. latipes (Parent, 1930), syntype Ƌ, femur III (photo: Günther Wöss); 68. P. bickeli sp. nov., holotype Ƌ, femur I; 69. P. perornatus Robinson, 1967, paratype Ƌ, tibia II; 70. P. latitibia sp. nov., paratype Ƌ, tibia I; 71. P. robinsoni sp. nov., holotype Ƌ, femur III. Scale bars = 0.2 mm.