Pherbellia stackelbergi

Vikhrev, Nikita E., Esin, Mikhail N., Yanbulat, Maria O. & Ruchin, Alexandr B., 2020, A list of the Sciomyzidae, Fanniidae and Muscidae (Diptera) of Mordovia, Amurian Zoological Journal XII (4), pp. 444-459 : 447-448

5. Pherbellia austera Meigen, 1830

Inorskoe Lake , 54.728°N 43.15°E, 20 May 2020, M. Esin, 1♂, 1♀ ; Pushta vill. env., 54.71°N 43.22°E, 18–22 May 2020, N. Vikhrev, 1♂ ; Taratinsky cordon, 54.74°N 43.09°E, 27– 29 June 2020, K. Tomkovich, 1♀ .

6. Pherbellia brunnipes Meigen, 1838 Inorskoe Lake , 54.728°N 43.15°E, 20 May 2020, N. Vikhrev, 1♂, 1♀; Pushta vill. env., 54.71°N 43.22°E, 18–22 May 2020, N. Vikhrev, 1♂, 1♀.

SYNONYMY. Pherbellia stackelbergi Elberg, 1965 was recorded for CET region of Russia, but P. brunnipes was not ( Rozkosny 2013). In our opinion, the description of P. stackelbergi was groundless. According to Elberg (1965) these two species differ as follows:

— Hypopygium as in Fig. 4 . Row of small hairs along lower frontal eye-margin extends on anterior half of frons, often almost till base ofantenna................... stackelbergi — Hypopygium as in Fig. 5 . Row of small hairs along lower frontal eye-margin extends only slightly beyond anterior orbital setae

.............................. brunnipes

First, Elberg never examined Meigen’s type and gave no reason why he regarded one part of specimens as a new species and other part as P. brunnipes . Thus, it was Elberg’s arbitrary decision, with equal grounds the choice could have been vice versa. Also, P. pusila Zetterstedt, 1938 or P. coxata Zetterstedt, 1938 or P. uliginosa Enderlein, 1939 , which were synonymized to P. brunnipes by earlier authors, were neither examined nor discussed.

We examined several specimens with and without hairs on lower eye-margin and found the male genitalia similar, with a visible shape of the sclerites strongly depending on the angle of view. Elberg’s sketchy drawings of the hypopygium are not helpful. For example, the anterior surstylus doesn’t really look as his drawings show ( Figs 4–5 ) but it looks like in Fig. 6 . Also the posterior surstylus looks like that in Fig. 5 , but its central lobe may look not rounded but pointed more similar to Fig. 4 under some angle of view.

Type series of P. stackelbergi is stored in the Zoological Institute, Saint Petersburg, it is in good condition. Holotype: ♂ ( Russia) , Leningrad oblast (Saint Petersburg reg.), Luga distr., Yaschera (58.9°N 29.9°E), A. Stackelberg, 6 August 1959. Paratypes: same locality as the holotype, A. Stackelberg, 1953–1959, 8♂ ; Tyumen oblast (presently Khanty-Mansi reg.), Samarovo (presently Khanty-Mansiysk) on Irtysh R., 4 June 1925, F. Fridolin, 1♂. There are about 40 specimens collected later at Luga district by A. Stackelberg, partly they were identified as P. brunnipes , partly as P. stackelbergi .

We also examined representative materials from Zoological Museum, Moscow and Zoological Institute, Saint Petersburg. It is 140 ♂ ♀ from: BELARUS, Vitebsk reg.; KA- ZAKHSTAN, Akmola reg.; RUSSIA: Amur, Arkhangelsk, Astrakhan, Kemerovo, Khakassia, Khanty-Mansi, Komi, Mordovia, Moscow, Novosibirsk, Omsk, Smolensk, Saint Petersburg, Tuva, Tver, Tyumen and Voronezh regions. P. brunnipes varies in the amount of strong setae on the upper katepisternum (2 or 3), in body colouration (more brown or yellow) etc. The amount of small hairs along the lower frontal eye-margin (proposed as a diagnostic character of P. stackelbergi ) gradually varies from 0 to 4 hairs, often the amount of these hairs is different on left and right sides of frons. Nothing indicates that P. brunnipes should be divided onto two or more species on the base of this character. Thus, Pherbellia brunnipes Meigen, 1838 = P. stackelbergi Elberg, 1965 , syn. nov.

Figures

Figs 4–6. Hypopygium of Pherbellia: 4 — stackelbergi Elberg, 1965; 5 — brunnipes Meigen, 1838 (from Elberg 1965); 6 — anterior surstylus (a.s.) of brunnipes Meigen, 1838 (from Vala 1989, fig. 28c)