Myolepta obscura ( Becher, 1882 )

Steenis, Jeroen Van, 2020, A new species of the genus Myolepta Newman (Diptera: Syrphidae), with short description and key to all species of the M. vara subgroup, Zootaxa 4750 (3), pp. 370-390 : 378-380

Myolepta obscura ( Becher, 1882)

Figs 2 A−B, 5A−B, 9A−B, 10C, 11B, 13B, 14A−B, 16A−B, 17D

Myiolepta obscura Becher, 1882: 250 ; the type is deposited in NMW

Myolepta obscura: Hauser 1998: 18 ; Reemer et al. 2005: 563; Ricarte et al. 2007: 1725 ; De Courcy Williams et al. 2011: 192; Sarýbýyýk 2011: 447 (as M. vara ); Prokhorov et al. 2018: 128

Material examined. France: “ France: Paris / Evry , Forêt de Sénart / 25. V.1997 / Leg. A. v. Eck ”, “ Myolepta subgroup / fig no JvSMo1-003”, 1♂ ( AET) ; “ Marais du Vigueirat / Sentier des Cabanes / N 43.53661 - E 4.75163 / 06.iv.2009 Camargue (F) / leg. E.P. de Boer ”, 1♂ ( MRL) ; “FRANKRIJK Gers / Pichoy ( Fources ) / 27-V-2006 / Leg. G.W.A. Pennards / on Tilia sp.”, “ Myolepta sub-group / fig no JvSMo1-008”, 1♀ ( WSB) ; “FRANKRIJK Gers / ( Fources ) / 04-VI-2005 / Leg. GWA Pennards”, 1♀ ( GPA) ; “ France; Gers / Fources / 43.99°N 0.20°E / 6.v.2019 A. v. Eck / on Crataegus flowers”, 1♀ ( AET) ; Portugal: “PORTUGAL Setúbal / Santiago do Cacém , 5 km / NNE; along N120 / N 38°03’15” W 8°39’27” / 29-iv-2017 243 m asl / W. van Steenis wvs06721”, “ Myolepta sub-group / fig no JvSMo1-012”, 1♀ ( WSB) ; Rumania: “ Herculane // leg. 7. V.1986 // Vl. Bradescu ”, 1♂, 1♀ ( NBC) .

Short description. Face grey pollinose except for non-pollinose shiny black vitta from central knob to mouth edge in male; frons in female with broad brown-grey pollinose fascia along eye margin reaching posteriorly as far as anterior ocellus. Scutum with dense, long, erect yellow pile; anterior margin of scutum broadly grey-pollinose; pleura almost entirely grey pollinose except non-pollinose and shiny on antero-ventral corner of anepisternum, an antero-dorsal to postero-ventral vitta on anterior anepisternum, on non-pilose part of katepisternum which is the antero-dorsal and medial part, ventro-medial part of katepimeron and almost entire meron; scutellum with very long yellow pile. Mesofemur with very long yellow pile, longest ventral pile about 1.25 times as long as width of metafemur. Terga II and III medially short appressed black pilose, along lateral margin with long yellow pile; tergum IV on anterior half with erect black pile and on posterior half with appressed long yellow pile; tergum I entirely and densely grey pollinose; sterna rather densely and grey-brown pollinose except lateral margin of terga II–IV with rather broad but short shiny and slightly pollinose vitta, in female tergum II entirely pollinose and tergum IV with place of lateral shiny vitta almost as densely pollinose as medial part of the sternum, only very vaguely shiny. Genitalia ( Figs 9A, B ): surstylus with strongly concave ventral margin, rounded apex and convex dorsal margin, some long yellow pile on baso-dorsal corner; hypandrium in ventral view strongly rounded basally and medially rather strongly constricted with rectangular apical part;superior lobe with wide and rounded incision apico-ventrally, apico-dorsal corner squarish; aedeagus baso-dorsally with rather long triangular extension and without apico-dorsal extension. Body length 11.4 mm (male), 10.4–12.1 mm (female); wing length 9.2 mm (male), 7.9–9.3 mm (female).

Remarks. This is the first record for this species from Portugal. The species is well known based on the original description and additional information in Reemer et al. (2005) and there was no need to study the type specimen. The species is clearly different from Myolepta nigra in several characters and it certainly is not a junior synonym of M. nigra as supposed by Hine (1913).

The picture in Sarıbıyık (2011) most likely shows a female specimen of Myolepta obscura and not M. vara , based on the long whitish pile on scutum and metafemur (not short, orange-brownish as in M. vara ).

Distribution. Widely distributed in central and southern Europe, from north-eastern Germany and northern France to Portugal and Greece, and eastwards to Azerbaijan.

Figures

FIGURE 2. Adult habitus of Myolepta hoverflies, male; A, C, E. dorsal view; B, D, F. lateral view. A, B. Myolepta obscura, Paris, France, fig no JvSMo1-003. C, D. Myolepta shikokuana, Fukui pref., Japan, fig no JvSMo1-004. E, F. Myolepta vara, Mechelen, the Netherlands, fig no JvSMo1-005. Scale 1.0 mm.

FIGURE 9. Male genitalia of Myolepta obscura, Paris, France, fig no JvSMo1-003. A. lateral view, partly distorted baso-dorsal margin. B. hypandrium, ventral view. Scale 0.5 mm. Dashed outline in Fig 9A indicates supposed outline of baso-dorsal margin of epandrium.