Merodon aureus

Veselić, Sanja, Vujić, Ante & Radenković, Snežana, 2017, Three new Eastern-Mediterranean endemic species of the Merodon aureus group (Diptera: Syrphidae), Zootaxa 4254 (4), pp. 401-434 : 430-431

Key to species subgroups and species within the Merodon aureus group sensu Radenković et al. (2011)

[Adapted from Šašić et al. (2016)]

1 Body pilosity very short ( Fig. 17 a), pile on dorsal surface of hind femur shorter than scapus; pile on tergites II and III shorter than basoflagellomere; distal half of hind tibia, and hind tarsi dorsally darkened ( Fig. 17 b).................................................................................... Merodon nisi sp. n. (Aegean island of Rhodes, Greece)

- Body pilosity longer, pile on tergites II and III as long as or longer than basoflagellomere........................... 2

2 Tibiae and tarsi mostly pale, at least basal half of fore and mid tibiae and tarsi ventrally............................. 3

- Tibiae and tarsi predominantly black...................................................................... 4

3 Tergites reddish.................................. Merodon dobrogensis subgroup (Eastern Mediterranean, 3 species)

- Tergites dark, exceptionally with small orange spots on lateral sides of tergites II and III..............................

.......................................... Merodon bessarabicus subgroup (central and southern Europe, 6 species) 4 Tergites II and III with pale lateral spots............................... Merodon unguicornis (Western Mediterranean)

- Tergites uniformly dark............................................................................... 5

5 Mesonotum only with pale pile...................... Merodon aureus subgroup (central and southern Europe, 3 species)

- Mesonotum, at least near wing base, with black pile......................................................... 6

6 Species with strong blue body lustre....................................... Merodon caerulescens (Aegean islands)

- Species with dark brown or greenish body lustre............................................................ 7

7 Tergites without microtrichia, shiny dark brown to black. Frons above antennae swollen and striated, with median tubercle above lunulae; metatarsus of hind leg with small dorsal depression.................................................................................................... Merodon robustus sp. n. (Aegean island of Samos, Greece)

- Tergites with at least a trace of microtrichose stripes or spots.................................................. 8

8 Body pile shorter; pile on scutellum in male shorter than hind basitarsus; tergites in female without microtrichose bands, or with small ones on tergites II and III............................................................................................... Merodon chalybeus subgroup (islands, coastal zone or low altitudes in Mediterranean, 4 species)

- Body pile longer; pile on scutellum in male as long as or longer than hind basitarsus; tergites II–IV in female with pair of microtrichose stripes......... Merodon cinereus subgroup (Central and South European mountains, 2 species complexes)

Figures

FIGURE 17. Merodon nisi sp. n., male: a—dorsal view (scale 1 mm); b—hind leg, lateral view (scale 0.5 mm); c—head, lateral view (scale 0.5 mm); d—head, anterior view (scale 0.5 mm).