Hydrotaea palaestrica Meigen, 1826

Hydrotaea palaestrica Meigen, 1826 View in CoL

Fig. 10

Hydrotaea mai Fan, 1965

Hydrotaea harpagospinosa Ni, 1982

Material examined. 90 specimens from: BE-

LARUS: Gomel, Minsk, and Mogilev regions.

EUROPEAN RUSSIA: Mordovia, Moscow, Pskov, Ryazan, and Tver regions .

ASIAN RUSSIA: Altai Rep Reg., Seminsky Pass, Turala River valley , 50.99 º N, 85.68 º E, 1350 m, 8– 12.07.2016, N. Vikhrev; 1♂ GoogleMaps ; Ust-Koksa , Koksa R. bank (50.29 º N, 85.55 º E), 25.06.2007, O. Kosterin, 1♂ GoogleMaps ; Buryatia Reg.: Kyren env., 51.7 ° N, 102.1 ° E, 750 m, 16– 19.06.2021, E. Makovetskaya, 1♂ GoogleMaps ; Turan env, 51.670 ° N, 101.684 ° E, 870 m, 09.06.2021, N. Vikhrev, 1♂ GoogleMaps ; Mondy env, 51.67 ° N, 101.04 ° E, 1250 m asl, 17.06.2021, E. Makovetskaya, 1♂ GoogleMaps ; Krasnoyarsk Reg.: Ergaki NP, 52.84 ° N, 93.25 ° E, 1450 m, 27– 29.06.2017, N. Vikhrev, 2♂ GoogleMaps ; Tanzybei env., 53.07 ° N, 93.13 ° E, 450 m, 28– 29.05.2018, N. Vikhrev, 1♂ GoogleMaps ; Krasnoyarsk env., Stolby , 56.11 ° N, 92.13 ° E, K. Tomkovich, 13– 19.06.2011, 1♂ GoogleMaps ;

Distribution. Palaearctic, from W Europe to 102 ° E.The Russian records are in a narrow range of latitudes from 50 ° N to 56 ° N., where H. palaestrica feeds on rotting meat, otherwise it is uncommon.

Discussion. Hydrotaea mai Fan, 1965 was described from China, Chinghai (Qinghai prov.), Haiyan [36.9 ° N, 101.0 ° E, 3000 m].It was synonymyzed with H. palaestrica Meigen, 1826 by Xue & Chao ( Xue, Chao 1998: 903). Fan ( Fan 2008: 1020) again proposed H. mai as a valid species, which differs from H. palaestrica as follows: prealar seta present; frons wider than in H. palaestrica ; only 1 pair of strong postsutural ac; mid coxa on posterior margin with a cluster of 5 setae. The width of the frons and amount of post ac setae are variable characters, they differ even in specimens collected in the same place and on the same date. The number of spinulose setae in the close-set cluster on the mid coxa is a character difficult to apply. Sometimes it is clear that the cluster consists of 3 setae, sometimes it presumably consists of 4 setae (Fig. 10), usually it is quite difficult to count these setae. The prealar seta is only applicable to males, in females of H. palaestrica (as well as in H. dentipes or H. similis ) it is always present. Among the examined material only one male from Turan, Buryatia, has a distinct prealar seta. However, this male has 2 post ac and a cluster on mid coxa consisting of 4 setae, so Fan’s diagnostic characters do not correlate with each other. That is why I follow Xue and Chao ( Xue, Chao 1998) and regard H. mai as a synonym. Pont ( Pont 2024) also regarded H. mai as a synonym.