Asindulum nigrum Latreille, 1805: 290

Fitzgerald, Scott J., 2023, The Nearctic species of Asindulum Latreille and Macrorrhyncha Winnertz (Diptera: Keroplatidae), Zootaxa 5351 (1), pp. 72-106 : 91-92

Asindulum nigrum Latreille, 1805: 290 .

Figs. 51–61

Platyura femoralis Meigen, 1818: 236 . Germany. Lectotype (MNHN).

Types. Not examined. France. (MNHN?; not found in type database).

Material Examined. FRANCE: Marais de Lavours , Malaise B, 8–11.vii.2008, P. Withers, 1m ( PCC) ; Marais de Lavours , Malaise B, 15–22.vii.2008, P. Withers, 1m ( PCC) ; UK: Hampshire, Ovington by River Itchen , 14.vii.1990, P. Chandler, 1f ( PCC) .

Diagnosis. Mouthparts extending well beyond apex of fore coxa and coxae black in both sexes. Male tergite 9 with both posterolateral and submedian lobes.

Comments. Based on the male terminalia, this species is undoubtedly the sister-species of A. coxale (see Comments under A. coxale ). Despite being widespread in Europe this species is apparently rather rarely collected ( Hedmark 2004, Ševčík pers. comm. 2022) and has been red-listed in Great Britain ( Falk & Chandler 2005) and Sweden ( Cederberg et al. 2010).

The head, wing, male terminalia, and female terminalia were illustrated by Matile (1975) and the head and male terminalia illustrated by Hutson et al. (1980). A photograph of the anterior portion of the male in lateral view was provided by Salmela, & Kaunisto (2015).

Distribution. Widespread in Europe; Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Ireland, Latvia, Poland, Russia (CET), Slovakia, Sweden, Switzerland, and UK ( Evenhuis 2006, Ševčík & Kurina 2011).

Biology. As noted in the Introduction, A. nigrum is known from fens and wetland habitats and is recorded visiting the flowers of Apiaceae (e.g., Angelica , Heracleum and Oenanthe fistulosa L.) and Saxifragaceae ( Saxifraga hirculus L.) ( Chandler 1991, Falk & Chandler 2005, Olesen & Warncke 1989a, 1989b).

Figures

FIGURES 51–54. Asindulum nigrum. 51. Male habitus. Scale = ca. 1.0 mm. 52. Male head, anterior. Scale = ca. 0.5 mm. 53. Female terminalia, dorsal. Scale = ca. 0.5 mm. 54. Female terminalia, ventral. Scale = ca. 0.5 mm. Abbreviations: cx1, coxa 1; cx2, coxa 2, ce, cercus; lbl, labellum; s7, sternite 7; s8, sternite 8; s10, sternite 10; t7, tergite 7.

FIGURES 55–59. Asindulum nigrum, male terminalia. 55. Dorsal. 56. Ventral. 57. Lateral. 58. Gonostylus, posterolateral (not to scale). 59. Gonostylus, posteroventral (not to scale). Scale bar = ca. 0.5 mm. Abbreviations: ce, cercus; gc, gonocoxite; gs, gonostylus; llgc, lateral lobe of gonocoxite; llt9, lateral lobe of tergite 9; smlt9, submedian lobe of t9; t9, tergite 9.

FIGURES 60–61. Asindulum nigrum, male terminalia including sperm pump. 60. Lateral. 61. Ventral. Scale = ca. 0.5 mm. Abbreviations: da, dorsal apodeme; ea, ejaculatory apodeme; gc, gonocoxite; t9, tergite 9; va, ventral apodeme.