Fannia fasciculata Loew, 1873

Вихрев, Е., 2019, Новые Ąанные По Ąвум Реąким Виąам (Diptera, Fanniidae), Amurian Zoological Journal XI (3), pp. 247-253 : 248-250

Fannia fasciculata Loew, 1873

Fannia baihualingensis Yan, Zhang, 2019 , syn. nov.

Figs 1, 3–8

Xu, Wang &

Taxonomic notes. Fannia fasciculata cannot be confused: abdominal tergites (at least 3 and 4) yellow with contrasting median vitta formed by black triangles; f3 strongly curved; near apex it has a tubercle with about 20 long (twice as long as femur width) ventral setae ( Figs 5–6 ); t2 widened in basal 1/3 and apical half, both widened parts covered with ventral hairs ( Fig. 7 ); tar2-1 (for this abbreviation see Vikhrev 2011, 60) projected and flattened ventrally; coxa bare at inner posterior margin; lower calypter projecting; genitalia characteristic: surstyli very long and slender, cercal plate small, bifurcate at apex (see Figs 1, 3, 4 ).

F. fasciculata was described from Baile Herculane (44.88 ° N 22.41 ° E), Romania. Since that time only two more records were known: Czechia ( Rozkosny et al. 1997) and Croatia ( Pont 2013), the female of F. fasciculata is still unknown.

Recently, a new species Fannia baihualingensis Yan, Xu, Wang & Zhang, 2019 was described from China, Yunnan prov., Gaoligong, Baihualing [more detail coordinates are 25.3 ° N 98.8 ° E, but the range of possible altitudes is very wide, from 700 to 3100 m asl], 25.07.2015, L.P. Yan & C. Wang, ♂ Holotype and 2 ♂ paratypes (Museum of Beijing Forestry University, China) ( Yan et al. 2019). I do not agree with the authors that it is a new species, I believe that we face just a new record of F. fasciculata .

Synonymy. Yan et al. (2019) compared F. baihualingensis with similar F. curvipes Malloch, 1924 (Nearctic species) and F. fasciculata . Let us regard their results. Yan et al. (2019) describe the terminalia of their species ( Fig. 1 ) as follows: “cercus of F. baihualingensis is slightly rounded, with the hook-like projection on its lower margin strongly curved outward.” Chillcott (1961) gave a ventral view on terminalia of F. curvipes ( Fig. 2 ) and described them as follows: “Cercal plate very slender on apical half and prolonged into an upcurved process.” I cannot find this process on Chillcott’s ventral drawing ( Fig. 2a ), although on his lateral view ( Fig. 2b ) this process is clearly drawn. The differences between two species can be summarized as follows:

— Legs yellow, only tarsi black. Cercal plate slender. Nearctic species distributed in northeastofUSA.............. curvipes Malloch

— Legs black, only knees yellowish. Cercal plate less slender. China, Yunnan .................. baihualingensis Yan, Xu, Wang & Zhang

Yan et al. (2019) illustrated genitalia of F.fasciculata by Hennig’s (1955, pl. 4, fig. 75) drawings ( Fig. 3 ). Hennig was among pioneers of diagnostic use of the male genitalia, his drawing of Fanniidae ( Hennig, 1955) are simplified but clear and helpful. (In my opinion Hennig’s approach is more useful than too intricate Chillcott’s drawings. For example, Hennig (1955, pl. 4, fig. 76) placed the drawing of the genitalia of Fannia armata Meigen, 1826 (another species with remarkably long surstyli) near that of F. fasciculata , so it is easy to see the difference between these species.) Based on Hennig’s drawing Yan et al. (2019) implied that the cercal plate of F. fasciculata has no curved process, while that of F. baihualingensis has. However, there is a more detail draw-

red spots Рис. 5–8. Fannia fasciculata : 5 — экземпΛяр из Московской обΛасти; 6 — экземпΛяр из южной Сибири; 7 — среΔняя нога, виΔ сзаΔи; 8 — распространение: ранее опубΛикованные нахоΔки — черным цветом, новые нахоΔки — красным ing of the genitalia of F. fasciculata in Rozkosny et al. (1997, 68, fig. 8e) reproduced here on Fig. 4 . On this drawing there is a curved process, though it looks placed on the epandrium instead of cercal plate. The situation is complicated by the fact that there is no verbal description of genitalia of F. fasciculata neither in Hennig (1955), nor in Rozkosny et al. (1997), nor anywhere else. Thus, the differences between the two species may be summarized as follows:

— t2 with 3–5 av. Cercal plate slender. Europe;SSiberia............ fasciculata Loew

— t2 with 2 av. Cercal plate less slender. China, Yunnan ................................ baihualingensis Yan, Xu, Wang & Zhang

Comparison of my specimens from Moscow region and S Siberia and the photos in Yan et al. (2019) shows additional variability. The mesonotum of the Siberian ( Fig. 6 ) and Chinese ( Yan et al. 2019, 155, fig. 1a) flies is glossy black, while in the specimens from Moscow ( Fig. 5 ) it is distinctly grey dusted. The abdominal tergite 1+2 is black in the Siberian fly ( Fig. 6 ), while it is mostly yellow in other specimens ( Fig. 5 and fig. 1d from Yan et al. 2019, 155).

How to treat these minute non-genitalic and doubtful genitalic differences between the considered taxa? To begin with, the taxa in question ( F. fasciculata , F. curvipes and F. baihualingensis ) obviously are closely related and share a set of unique diagnostic characters. The strongly sclerotizated surstyli which are responsible for the external contact between males and females are the same. Thus, the crossbreeding between them is likely possible, but we have little hope of knowing that for sure. Recently similar difficulties were discussed by Vikhrev, Yanbulat (2019) where they tried to draw attention to disor- der of today’s taxonomy from oversplitting trend. In that publication they recommended not to forget the basic law of parsimony (Occam’s presumption) and to offer only wellgrounded changes in accepted taxonomy. According to this approach F. curvipes should be regarded as a valid species unless otherwise is proven. At least it is reliably geographically isolated, it may be easy distinguished due to yellow legs and it is accepted as valid species during almost 100 years. Described just this year F. baihualingensis cannot be reliably distinguished and is not isolated, so Fannia fasciculata Loew, 1873 = F. baihualingensis Yan, Xu, Wang & Zhang, 2019 , syn. nov., unless otherwise is proven.

New records. Russia: Moscow reg., Kostino env., 56.316 ° N 37.768 ° E, 2.06.2010, N. Vikhrev, 1 ♂ ;

Krasnoyarsk reg., Ergaki NP, 52.839 ° N 93.254 ° E, 1450 m asl, 27– 29.06.2017, N. Vikhrev, 1 ♂ (both Zoological Museum of Moscow University, Russia) .

Distribution. F. fasciculata turned to be widely distributed (see Fig. 8 ). Initially I supposed that the species is uncommon because it needs some rare conditions. However, a large series of F. curvipes was collected in mixed deciduous forest at 1220 m asl in North Carolina and larvae were found there also in oak-leaf litter (Chillcott 1961), so at least closely related Nearctic species has ecological requirements typical for Fannia . Then, I can offer other explanation: F. fasciculata was described from Europe but it is originated from S-E Palaearctic. In the homeland, F. fasciculata was unknown till Yan et al. (2019) publication because this region was generally poorly studied, while in Europe the species probably began to spread only recently.

Figures

Figs 1–4. Male terminalia: 1 — Fannia baihualingensis, ventral view (from Yan et al. 2019); 2 — F. curvipes, ventral (2a) and lateral (2b) views (from Chillcott 1961); 3 — F. fasciculata, ventral view (from Hennig 1955); 4 — F. fasciculata, ventral view (from Rozkosny et al. 1997) Рис. 1–4. ГенитаΛии самца: 1 — Fannia baihualingensis, вентраΛьно (из Yan et al. 2019); 2 — F. curvipes, вентраΛьно (2a) и ΛатераΛьно (2b) (из Chillcott 1961); 3 — F. fasciculata, вентраΛьно (из Hennig 1955); 4 — F. fasciculata, вентраΛьно (из Rozkosny et al. 1997)

Figs 5–8. Fannia fasciculata: 5 — specimen from Moscow region; 6 — specimen from S Siberia; 7 — mid leg, posterior view; 8 — distribution: previous records — black spots, new records —