This pretty little syrphid fly, Chalcosyrphus piger (or pigra), was displaying and/or basking from the railing of my deck. These flies are said to be "hilltoppers", that is, they gather at high places for mating, with males tending to stake out territories. These flies are all dark except for the bright red abdomen and are said to be Batesian mimics of spider wasps with this pattern, esp. genus Astata. Length about 10 mm.Identification as to species level in this genus is tough, but see the BugGuide page linked above, and especially this plate from Syrphidae of Ontario. Note short appressed (not erect) hairs on thorax, tarsi all black. Also, this is a common species listed in the North Carolina State University entomology collection, so I think I've got this one.
The green halteres tend to become green whee eggs are being developed [Jrgen Peters via diptera.info] and this female seems to be about starting oviposition.Phylum: Arthropoda LATREILLE, 1829 (arthropods, Gliederfer)Subphylum: Hexapoda BLAINVILLE, 1816 (Sechsfer)Class: Insecta LINNAEUS, 1758 (insects, Insekten)Subclass: Pterygota LANG, 1888 (Fluginsekten)Infraclass: Neoptera MARTYNOV, 1923Order: Diptera LINNAEUS, 1758 (true flies, mosquitoes & gnats, Fliegen & Mcken)Suborder: Brachycera SCHINER, 1862Infraorder: Muscomorpha [Syn.: Cyclorrhapha]Superfamily: SyrphoideaFamily: Syrphidae SAMOUELLE, 1819 (hoverflies or flower flies, Schwebfliegen)Subfamily: Syrphinae SAMOUELLE, 1819Tribus: Bacchini Genus: Melanostoma SCHINER, 1860[det. johnes81, 2017, based on this photo via diptera.info]Melanostoma scalare FABRICIUS, 1794 (Matte Schwarzkopf-Schwebfliege)[det. Stephane Lebrun, 2017, based on this photo via diptera.info]Central Germany, N-Hesse: vic. Kassel (Brasselsberg) ca. 400m asl., 21.05.2015IMG_6506
Syrphidae: Sphaerophoria macrogaster Here is the Hover fly getting ready to lay her eggs on our parsley. When the larva hatch, they will also eat the aphids. Yay! We have lots of aphids for them to eat!! Photo: Jean