Brachycercus harrisella Curtis, 1834

Martynov, Alexander V., 2018, New records of some rare mayflies (Insecta, Ephemeroptera) from Ukraine, Ecologica Montenegrina 16, pp. 48-57 : 54

Brachycercus harrisella Curtis, 1834

This species is widely distributed all over Europe, but rare in the Mediterranean area ( Bauernfeind & Soldán 2012). In Ukraine B. harrisella also belongs to rare species; it was known only from the Dnister River, middle and low courses of the Desna River, upper course of the Dnipro River ( Polishchuk 1964; Invertebrates… 1989; Nedostup 1994). We registered larvae of this species ( Fig. 13 ) at different points of the Stvyga River within Rivne Region ( Figs 14, 16 ).

Habitat: In all sampling places the river had the moderate current velocity (from less than 0.05 to 0.5 m /s) and the bottom of sand or silted sand ( Fig. 16 ). The main number of larvae was collected in microhabitats with accumulations of detritus and current velocity 0.1–0.3 m /s. Additional parameters of waterbody in sampling places were: water temperature 21–22°C, water hardness 47–49 ppm, pH 7.4–7.5.

Material: Ukraine, Rivne Region: 2 larvae, vicinity of Blazhove village, Stvyga River , 51.419617, 27.351633, h – 146 m a.s.l., Martynov A. V. leg., 3.07.2017 – IN Riv 3 Brahar ; 7 larvae, territory of Glynne village, Stvyga River , 51.529883, 27.421400, h – 144 m a.s.l., Martynov A. V. leg., 5.07.2017 – IN Riv 5 Brahar ; 18 larvae, Stvyga River, between Glynne and Poznan’ villages, 51.563133, 27.428250, h – 147 m a.s.l., Martynov A. V. leg., 5.07.2017 – IN Riv 1 Brahar /1–2 ; 2 larvae, vicinity of Poznan’ village, Stvyga River , 51.591450, 27.477868, h – 139 m a.s.l., Martynov A. V. leg., 5.07.2017 – IN Riv 4 Brahar .

Figures

Figures 9–13. Larvae and imago of some registered species: 9. – Isonychia ignota (Walker, 1853), total view of larva, scale bar 2 mm; 10. – Baetopus tenellus (Albarda, 1878), total view of larva, scale bar 1 mm; 11. – Metreletus balcanicus (Ulmer, 1920), total view of larva, scale bar 2 mm; 12. – the same species, genitalia and posterior part of abdomen, male imago, ventral view, scale bar 1 mm; 13. – Brachycercus harrisella Curtis, 1834, total view of larva, scale bar 2 mm.

Figures 14–18. New collection sites of the investigated species within Ukraine: 14. – map showing new sites (red circles – Palingenia fuliginosa (Georgi, 1802); yellow circles – Isonychia ignota (Walker, 1853); green circle – Baetopus tenellus (Albarda, 1878); blue circles – Brachycercus harrisella Curtis, 1834; red quadrates – Siphlonurus aestivalis Eaton, 1903; yellow quadrate – Metreletus balcanicus (Ulmer, 1920)); 15. – Styr River, (vicinity of Stara Rafalivka village, July 2017); 16. – Stvyga River (vicinity of Poznan’ village, July 2017); 17. – bay of Desna River (vicinity of Prydesnyans’ke village, May 2017); 18. – Salva River (territory of Bukove village, May 2017).