Flagellisargus (Flagellisargus) cf. sinicus J. Zhang, 2012a

Zhang, Junfeng, 2017, New findings of Flagellisargus J Zhang, 2012 (Diptera, Brachycera, Archisargidae), with discussion of the placements of some controversial taxa, Deutsche Entomologische Zeitschrift 64 (2), pp. 111-122 : 112-114

Flagellisargus (Flagellisargus) cf. sinicus J. Zhang, 2012a Fig. 4

Flagellisargus sinicus J Zhang, 2012a, 879-880, figs 1-3.

Description.

Moderate-size female archisargid fly; body yellowish brown (Fig. 4A). Head moderately large, nearly semiglobose; eyes large, dichoptic, occupying most parts of head; antenna long, clavate, nearly 1.5 times as long as head length, scape not elongated, slightly longer than wide, pedicel short, subquadrate, wider than long, flagellum elongate-conical, nearly three times as long as wide, with a darkish brown longitudinal furrow near to its outer margin and connecting base of arista which is darkish brown, stylate, and distinctly curved inwards, ratio of scape, pedicel and flagellum 2.0:1.0:9.0, arista (or stylus) about a quarter of flagellum length (Fig. 4B).

Thorax nearly globose, as long as wide, slightly wider than head (Fig. 4A). Wing narrow and long, about 3.5 times as long as wide, C terminating at wing tip; C, Sc, R1 and Rs clearly stouter than M1 and M2; Sc long, more than one half of wing length; R1 straight, nearly fourth-fifths of wing length; origin of Rs slightly basad to wing midlength, Rs stem short, nearly as long as section bR4+5; R2+3 straight, ending at C far apart from R1 end; section dR4+5 straight, nearly four times as long as section bR4+5, 3.7 times as long as R5, R4+5 fork at level of R2+3 end, R4 shorter than R5, both veins dR4+5 and R5, more or less, not in line, R5 slightly curved downwards, ending at wing tip; ratio of costal sections Sc-R1, R1-R2+3, R2+3-R4 and R4-R5 1.0:0.3:0.4:0.4; ratio of Rs, bR4+5, dR4+5 and R5 1.0:1.0:4.1:1.8; M1 and M2 almost straight, subparallel (Fig. 4A). Femur of hindleg long and stout, clavate, nearly reaching posterior margin of third abdominal segment, tibia at least with a needle-like spur, and shorter than width of tibia (Fig. 4C).

Abdomen with nine segments visible, nearly cylindrical, just a little narrower than thorax, 1.9 times longer than head (excluding antenna) and thorax combined; each of tergites with a wide, longitudinal, intermediate marking which is darkish brown; apex of abdomen with a scelerotized, needle-like ovipositor, and slightly longer than ninth segment (Fig. 4A).

Dimensions.

NIGP DHG 201702: length of body (excluding antenna and ovipositor), 9.6 mm; head, 1.3 mm; thorax, 2.1 mm; abdomen (excluding ovipositor), 6.2 mm; ovipositor ca. 0.5 mm. Length of wing, 7.9 mm, width of wing, ca. 2.3 mm.

Distribution.

The "Daohugou Formation" (Daohugou Bed), Callovian-Oxfordian; Daohugou, Wuhua, Ningcheng, Inner Mongolia, China.

Remarks.

On the following characters, this fly could be assigned to Flagellisargus (Flagellisargus) : body (excluding antenna and ovipositor) moderate-size (more than 9 mm long); antennal scape short (not elongated); arista (or stylus) well developed (about a quarter of flagellum length); fork of R4+5 just at level of R2+3 end; and R5 ending at wing tip.

Owing to having special characteristics (antennal flagellum with a darkish brown longitudinal furrow near to its outer margin and connecting base of arista and a tibial spur of hindleg well developed) this specimen shows close similarities in antennal and leg’s structures to that of the known species Flagellisargus (Flagellisargus) sinicus . Unfortunately, its wing is incompletely preserved, and the discal cell, posterior branch of M, CuA, CuP and crossvein m-cu are rather ambiguous or invisible. For this reason, this impression fly could only be identified as Flagellisargus (Flagellisargus) cf. sinicus .