Orthonevra incisa (Loew, 1843)

Prokhorov, A. V., Popov, G. V., Shparyk, V. Yu. & Vasilyeva, Yu. S., 2023, New Records Of Hoverflies (Diptera, Syrphidae) From Ukraine. Vi, Zoodiversity 57 (2), pp. 125-142 : 128-129

Orthonevra incisa (Loew, 1843) (figs 11–13, 17–19)

M a t e r i a l e x a m i n e d. Ukraine. Kyiv Region: Nova Buda env.: 50.68365 N 29.703609 E, overgrown damp road in mixed forest, 23.04.2016, 1 Ơ; 50.684214 N 29.708405 E, swampy glades in mixed forest, on flowers of Caltha palustris , 5.05.2021, 2 ♀ (A. Prokhorov) .

D i s t r i b u t i o n. Hungary, Poland, Romania; Russia (Western Siberia); Turkey ( Stackelberg, 1953; Bańkowska, 1963 (as Chrysogaster ); Peck, 1988; Stănescu & Pârvu, 2005; Tóth, 2011, 2014; Barkalov & Mutin, 2018; Mielczarek & Żóralski, 2021; van Steenis et al., 2021; Wakkie, 2021); Ukraine (first record*).

* The species is listed on the GBIF website ( Orthonevra incisa …, 2022), where four specimens from Ukraine (May 1943) are presented by South African National Biodiversity Institute and KwaZulu-Natal Museum. Two of them are recorded from Kherson Region, near delta of Dnipro River, 46.6N 32.6E. Since we cannot verify this data, we present our specimens as new to the fauna of Ukraine .

Figs 11–16. Orthonevra incisa (11–13) and O. brevicornis (14–16): 11, 14 — males, dorsal view; 12, 15 — males, lateral view; 13, 16 — females, dorsal view.

D i a g n o s i s. Orthonevra incisa (Loew, 1843) belongs to the species group with entirely black legs. This species is very similar to Orthonevra brevicornis (Loew, 1843) (figs 14–16, 20–22) in having postpedicel is almost circular (1–1.5 times longer than wide) with pale ventral part.

The male of Orthonevra incisa differs from O. brevicornis by the narrower frontal triangle ( fig. 17 ), (in O. brevicornis , the frontal triangle wider, as on fig. 20 ); postpedicel with dorsal and ventral sides rounded (fig. 12, 17) (in O. brevicornis , postpedicel slightly broadened to apex, as on fig. 15, 20); surstylus not broadened on basal half ( fig. 18 ) (in O. brevicornis , surstylus distinctly broadened on basal half, as on fig. 21 ) ( Stackelberg, 1953; van Veen, 2010).

The female of Orthonevra incisa can be easily distinguished from O. brevicornis by the abdominal tergite 5 with deep incision at hind margin ( fig. 19 ) (in O. brevicornis , abdominal tergite 5 without incision, as on fig. 22 ), postpedicel with dorsal and ventral sides rounded with a slightly pointed top (in O. brevicornis , postpedicel slightly broadened to apex, as in male).

Orthonevra incisa is also very similar to O. plumbago (Loew, 1840) , but according to Stackelberg (1953) differs from it by almost circular postpedicel (in O. plumbago , postpedicel about 2 times longer than wide, as in fig. 11 in the mentioned paper). The more or less reliable distinguishing feature by which O. incisa can be easily separated from both closely related species, is the entirely pollinose sternum 1 (in O. brevicornis and O. plumbago , all sterna shiny) ( Ricarte et al., 2022).

Subfamily Pipizinae

Figures

Figs 17–22. Orthonevra incisa (17–19) and O. brevicornis (20–22): 17, 20 — male head, frontal view; 18, 21 — male abdomen, terminal part, ventral view; 19, 22 — female abdomen, terminal part, dorsoposterior view.