Melanostoma mellarium (Meigen, 1822) Meigen, 1822

Haarto, Antti & Stahls, Gunilla, 2014, When mtDNA COI is misleading: congruent signal of ITS 2 molecular marker and morphology for North European Melanostoma Schiner, 1860 (Diptera, Syrphidae), ZooKeys 431, pp. 93-134 : 105-108

Taxon classification Animalia Diptera Syrphidae

Melanostoma mellarium (Meigen, 1822) stat. n. Figs 5C, 6C, 7C, 8C, 9C, 10C, 11C, 12D, 13A, 14C

Syrphus mellarius Meigen, 1822.

Melanostoma mellinum var. melanatus Kanervo, 1934, syn. n.

Type-locality.

The locality of the lectotype is not indicated in the original label. Peck (1988) gave the following information "Auf Wiesen und in Wäldern nicht selten''"?Stolberg near Aachen''[Germany].

Types.

Lectotype of Melanostoma mellarium : female, pinned, deposited in MNHN. Original label: 'Meigen 1486 40 / mellinum type’. Here the lectotype is designated to fix the concept of Melanostoma mellarium (Meigen) and to ensure the universal and consistent interpretation of the same. Labelled: 'LECTOTYPE Melanostoma mellarium (Meigen, 1822), Haarto & Ståhls des. 2013'. Images from MNHN.

Lectotype

of Melanostoma mellinum var. melanatus: female, pinned, deposited in MZT. Original label: 'Haukilampi, 28.4.28 '‘ Lectotype Melanostoma mellinum var. melanatus Kanervo, Haarto & Ståhls des. 2014'.

Additional material studied.

DNA voucher specimens in MZH (Table 1) 17 males and 30 females in MZH; 25 male and 25 female specimens in AHPC.

Male.

Head: Colour black. Angle of approximation of eyes 80°-90°. Eye contiguity about as long as frontal triangle. Ocellar triangle slightly longer than wide with dark pile and with indistinct grey dusting. Occiput very narrow and dorsally with dark pile and laterally with pale pile. Frontal triangle shining with indistinct grey dusting. Lateral parts of frontal triangle with dark pile. Face shining with indistinct grey dusting. Lateral parts of face with pale and dark pile. Gena about as wide as basoflagellomere and with thin greyish dusting. Antenna mainly dark brown, basoflagellomere usually with a yellow spot baso-ventrally. Basoflagellomere about 1.3 times as long as its width. Arista usually brown and about twice as long as basoflagellomere. Longest pile of arista at most half width of arista at base as in Fig. 4B.

Thorax: Scutum shining black except for thin greyish dusting at anterior margin. Scutum usually with pale brown and dark erect pile and with shorter semi-adpressed pale pile on anterior margin. Pile rarely mainly dark on scutum. Anterior part of scutum with short erect pile which length about fourth part of length of scutellum. Postpronotum totally covered by thin greyish dusting. Notopleuron covered by indistinct greyish dusting. Scutellum shining black with pale and dark erect pile at its dorsum and posterior margin. Scutellum only pale pile at its ventral side. Pleura black and usually with only thin grey dusting and usually more distinctly shining on posterior part of anepisternum, anterior part of anepimeron and dorsal part of katepisternum. Pleura with pale erect pile. Calypter brownish with pale brownish pile on margin. Halter yellow with slightly darkened base of stem. Wing: Usually completely microtrichose, rarely with small bare area on base of cell BM. Membrane with slightly brownish ting. Stigma yellowish brown.

Legs: Coxa black with grey dusting. Trochanter dark brown. Femur usually mainly black except yellow apical part. Tibia usually mainly yellow with dark brown ring varying size. Metatibia usually with a longer dark ring than other tibiae. Tarsus dark brown except mesotarsus with two basal segments yellow. Leg with pale and dark pile mixed.

Abdomen: Terga dark brown or black with weak greyish dusting. Tergum 2 with pair of yellow oval maculae. Terga 3 and 4 with pair of yellow subrectangular maculae. Terga 1 and 2 laterally with long pale pile. Terga with varying amount of dark and pale semi-adpressed pile outside of yellow maculae. Only pale pile on yellow maculae. Terga 2, 3 and 4 each about 1.4 times as long as its width. Sterna with weak dusting and with pale semi-adpressed pile. Sternum 2 about 1.6 times as long as its width at its posterior margin. Sternum 3 about 1.5 times as long as its width at its anterior margin. Sternum 4 about 1.4 times as long as its width at its anterior margin. Shape of sterna 2-4 are shown in Fig. 5C. Male genitalia: Cercus and surstylus as in Fig. 6C. Postgonite long and with distinct ridges laterally (Figs 7C, 8C). Postgonite ventrally in Fig. 9C. The hypandrial, margin at postgonites with long triangular projections, index DL less than 1.2 (Figs 10C, 11C).

Female.

Similar to male, but differs as follows:

Head: Frons shining except greyish dusted triangles. Frons at level of front ocellus slightly narrower than length of antenna. Dorsal part of frons with dark pile and ventral part of frons with pale pile. Occipital orbit as broad as two diameters of an ocellus and usually dorsally with pale and dark pile and laterally with pale pile. Scape and pedicel brown or yellowish brown.

Thorax: Scutum and scutellum with short pale pile. Calypter whitish yellow with whitish pile at edge. Wing: Indistinctly brownish tinged. Stigma pale yellowish brown.

Legs: Femur and tibia usually mainly yellow with dark brown ring varying size. Metaleg usually largely darker than other leg.

Abdomen: Terga indistinctly grey dusted. Tergum 2 without or with a pair of small yellow oval maculae. Terga 3 and 4 usually with a pair of small yellow elongated triangular maculae. Tergum 5 at anterior margin without or with pair of short yellow maculae. Tergum 2 about 0.6 times as long as its width at its posterior margin. Tergum 3 about 0.7 times as long as its width at its posterior margin. Tergum 4 about 0.9 times as long as its width at its posterior margin. Sternum 2 about 0.8 times as long as its width at its posterior margin. Sternum 3 about 0.8 times as long as its width at its anterior margin. Sternum 4 about 0.8 times as long as its width at its anterior margin. Shape of sterna 2-4 are shown in Fig. 12D.

Length

(25 males and 25 females): Body 7-9 mm.

Distribution.

We have verified specimens from Fennoscandia and central Europe, but data for a more detailed distributional map is presently not available.