Pseudosympycnus Robinson

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 : 232-233

Pseudosympycnus Robinson

Pseudosympycnus Robinson, 1967: 901 .

Type-species: Sympycnus palpiger Van Duzee (1931: 177) , by original designation.

Diagnosis. Male. Head. Face and palpus covered with silvery pruinosity, palpus often enlarged, rounded, covered with scale-like setae (MSSC) ( Figs 12–19, 21, 22, 24–31, 33, 34, 36–39 ). Antenna brown to black; scape dorsally bare, arista-like stylus dorsal. Thorax. Acrostichals biserial; 5 conspicuous pairs of dorsocentrals (with pair of reduced dorsocentral setae anteriad, about 1/3 to 1/2 of length of first pair) ( Figs 72–73 ); scutellum with one pair of setae, but sometimes also with numerous hairs on posterior margin ( Figs 72–73 ). Legs. Femur II with anterior and posterior preapical setae; femur III with anterior preapical seta. Tarsus I and distal segments of tarsus III modified in shape and/or setae, noticeably It 2 (shortened, distorted and/or ornamented with modified setae (MSSC) ( Figs 40–65 ). Abdomen. Long and slender, cylindrical, with 6 setose segments, dark brown, often with entire tergite 1 and tergites 2–3 yellow laterally. Hypopygium small, surstylus with two lobes, epandrial lobe short ( Figs 75, 76 , 79–81 ). Female. Similar to males (except for MSSC), except: Head. Face also pruinose and slightly narrowed at middle, palpus not enlarged, but generally covered with silvery pruinosity ( Figs 20, 23 , 32, 35 ).

Remarks. Males of Pseudosympycnus are easily recognized from other genera by their striking modifications on legs, and by the enlarged and rounded palpus. Females can be differentiated from Nearctic and Neotropical females of Sympycnus by the presence of two regular rows of acrostichal setae in Pseudosympycnus (0–1 rows in Sympycnus ) (J. Runyon, pers. comm.). Females of Pseudosympycnus were not confidently sorted to species at this stage, as more information is required to make these decisions.

It is noteworthy that a number of species studied here were taken on moist rocks near waterfalls. The entire type series of Pseudosympycnus bickeli sp. nov., for example, was found in this biotype, which is similar to where specimens of P. perornatus (“on wet rocks in deeply shaded ravine”, “on surface of dam” and “on rocks near stream”; Robinson 1967) and P. latitibia sp. nov. (“on stones in streams”) were collected. Also, the type locality of P. araza sp. nov. and P. maroaga sp. nov. are both close to waterfalls ( Figs 82–85 ). Moreover, specimens of P. singularis were often collected close to waterfalls in Belize (J. Runyon, pers. comm.). These data may indicate habitat preferences in the genus or at least part of the known species.

Figures

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 16–29. Pseudosympycnus Robinson. Head. 16–17. P. albipalpus (Parent, 1930), identified specimen from State of Amapá, Brazil, 16. Anterior view. 17. Lateral view; 18–20. P. araza sp. nov. 18–19. Paratype Ƌ. 18. Anterior view. 19. Lateral view. 20. Possible ♀ (see text), anterior view; 21–23. P. bickeli sp. nov. 21–22. Holotype Ƌ. 21. Anterior view. 22. Lateral view. 23. Paratype ♀, anterior view; 24–25. P. latipes (Parent, 1930), identified specimen from State of Acre, Brazil. 24. Anterior view. 25. Lateral view; 26–27. P. latitibia sp. nov., paratype Ƌ. 26. Anterior view. 27. Lateral view; 28–29. P. maroaga sp. nov., holotype Ƌ. 28. Anterior view. 29. Lateral view. Scale bars = 0.2 mm.

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 72–73. Pseudosympycnus Robinson. Mesonotum, dorsal view. 72. P. latitibia sp. nov., paratype Ƌ; 73. P. perornatus Robinson, 1967, paratype Ƌ. Scale bars = 0.2 mm.

FIGURES 40–41. Pseudosympycnus Robinson. Male leg I, posterior view. 40. P. sehnali sp. nov., paratype Ƌ; 41. P. perornatus Robinson, 1967, paratype Ƌ. Scale bars = 0.2 mm.

FIGURES 42–54. Pseudosympycnus Robinson. Male tarsus I, II and III. 42–43. P. albipalpus (Parent, 1930), identified specimen from State of Amapá, Brazil. 42. Tarsus I. 43. Tarsus III; 44–46. P. araza sp. nov., holotype Ƌ. 44. Tarsus I. 45. Tarsus II. 46. Tarsus III; 47–48. P. bickeli sp. nov., holotype Ƌ. 47. Tarsus I. 48. Tarsus III; 49–50. P. latipes (Parent, 1930), identified specimen from State of Acre, Brazil. 49. Tarsus I. 50. Tarsus III; 51–52. P. latitibia sp. nov., paratype Ƌ. 51. Tarsus I. 52. Tarsus III; 53–54. P. maroaga sp. nov., holotype Ƌ. 53. Tarsus I. 54. Tarsus III. 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 75–78. Pseudosympycnus bickeli sp. nov. 75–76. Paratype Ƌ hypopygium, left lateral view. 77–78. Paratype ♀ ter- minalia. 77. Dorsal view. 78. Lateral view. Scale bars = 0.1 mm. Abbreviations: acanth = acanthophorite; bac scl = bacilliform sclerite; cerc = cercus; d sur = dorsal lobe of surstylus; ej apod = ejaculatory apodeme; epand lb = epandrial lobe; hypd = hypan- drium; hypd ap = hypandrial apodems; hypd ar = hypandrial arms; pgt = postgonite; ph = phallus; sbepand scl = subepandrial sclerite; st 8 = sternite 8; tg 8 = tergite 8; v sur = ventral lobe of surstylus.

FIGURES 79–81. Pseudosympycnus Robinson. Hypopygia, left lateral view. 79. P. araza sp. nov., paratype Ƌ; 80. P. latitibia sp. nov., paratype Ƌ; 81. P. sehnali sp. nov., paratype Ƌ. Scale bars = 0.1 mm. Abbreviations: cerc = cercus; d sur = dorsal lobe of surstylus; epand lb = epandrial lobe; hypd = hypandrium; v sur = ventral lobe of surstylus.

FIGURES 82–85. Collection localities and habitats of Pseudosympycnus species. 82. Type-locality of P. araza sp. nov. (Araza river, Cusco, Peru. Photograph: J.A. Rafael, 2012); 83. Type-locality of P. bickeli sp. nov. (unnamed waterfall, Serra da Mocidade, Roraima, Brazil. Photograph: F.F. Xavier F., 2016); 84. Type-locality of P. sehnali sp. nov. (Reserva Florestal Adolpho Ducke, Manaus, Amazonas, Brazil. Photo: M.M.M. Soares, 2018); 85. Type-locality of P. maroaga sp. nov. (Iracema Falls, Presidente Figueiredo, Amazonas, Brazil. Photograph: M.M.M. Soares, 2018).