The Western Roundtail (Melanostoma mellinum) is a small, dusky-yellow and black, holarctic species. Identifiable by abdomen pattern. Males lack the flattening or broadening of the front legs characteristic of similar Sedgesitter (Platycheirus) males. Adults can be found on leaf surfaces where they feed on the pollen of grasses (Poaceae) and other wind-pollinated plants but also visit a variety of flowers. Larvae are entomophagous, mainly aphids.
Flight dates: April – July
Flowers: Rue Anemone, Dandelion, Wild Plum
Similar species: Platycheirus quadratus
The Long-nosed Swamp Fly (Eurimyia stipata) is a small, gray, yellow, and black, Holarctic species. Unlike most other Syrphidae, female and male eyes are separated. Males have thinner abdomens and are the more colorful. The larvae have long tails and are found in wet areas with decaying vegetation at the edge of ponds and other wetlands.
The taxonomy of this species is a little messy. In Europe it’s Anasimyia lineatus. Here it has been known as Lejops lineatus or Lejops (Eurimyia) lineatus or Eurimyia lineatus, and currently Eurimyia stipata. The common name, Long-nosed Swamp Fly, simplifies the problem.
Flight season: May – July
Flowers: Sweetflag Iris, Spiderwort, Creeping Thistle
Similar species: Lejops bilinearis and Parhelophilus sp.