Eumerus sogdianus Stackelberg, 1952

Mutin, V. A. & Barkalov, A. V., 2018, New data on the hover-flies of the genus Eumerus (Diptera: Syrphidae) from Russia, Far Eastern Entomologist 363, pp. 11-20 : 17-18

Eumerus sogdianus Stackelberg, 1952

Figs 20–21

Eumerus sogdianus Stackelberg, 1952: 390, lectotype (designated by V. Richter and S.

Kuznetsov (2007): ♂, Tajikistan: Dushanbe: «Сталинобад, дол. р. Кафирниган 20 V

1943 (Штакельберг)» (examined) [ZIN].

Eumerus arat Violovitsh, 1981: 93, holotype: ♂, Russia: Tuva: « Тува, Заболоченный берег оЗ. Амдайгын- Холь, 5.VII 1963 (Н. Виолович)» (examined) [ZIN]; syn. n.

SPECIMENS EXAMINED. Russia: Novosibirskaya oblast: Karasuk district, environs of

Karasuk, 8. VI 1982, 1 ♂ (A. Barkalov); Altai Republic: Gorno-Altaisk Town, 22.VI 1983, 1

♂ (A. Barkalov).

– Eumerus sogdianus ; 20 – male genitalia, lateral view; 21 – female head, dorsal view; 22 –

epandrium of E. turcmenorum , lateral view.

DIAGNOSIS. This species belongs to the E. strigatus species-group and is very similar to Eumerus consimilis , E. montanum , E. roborovskii and E. strigatus . The male can easily be distinguished by the genitalia ( Fig. 20 ) and the form of the 4 th sternum from males of these other species. Females of Eumerus sogdianus , E. consimilis , E. montanum and E. strigatus do not have stable specific characters to be distinguished, but they all are characterized by their large oval or rounded basoflagellomeres, unlike the female E. roborovskii with its elongated basoflagellomere. Female E. sogdianus from Europe and Central Asia ( Tajikistan)

have an isosceles ocellar triangle. This character is not stable among Siberian females, but they as well as females from Central Asia have a narrower frons with its width in front of the ocellar triangle 4.3-4.5 times less than the head width ( Fig. 21 ).

REMARKS. Comparison of the lectotype of Eumerus sogdianus and the holotype of E.

arat made it possible to establish their species identity, and therefore we synonymize E. arat with E. sogdianus . The paper of Violovitsh (1981) with the original description of E. arat does not contain any mention of E. sogdianus . This species was also not included in his key to Siberian syrphids (Violovitsh, 1983).

DISTRIBUTION. Russia: Crime, West Siberia, Tyva Republic. – Europe, Transcaucasus,

Kazakhstan, Central Asia, Mongolia, China.

Figures

Figs 19–22. Eumerus ssp.: 19 – female head of Eumerus strigatusm, dorsal view; 20–21