''Anasimyia chrysostoma'', the lump-legged swamp fly , is a fairly common species of

syrphid fly Hover flies, also called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while ...

observed across the United States and Canada. Hoverflies can remain nearly motionless in flight. The adults are also known as flower flies for they are commonly found on flowers from which they get both energy-giving

nectar Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...

and protein-rich

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

. Larvae of this genus are of the rat-tailed type living in aquatic environments.

References

Eristalinae Insects described in 1830 Insects of the United States Hoverflies of North America Insects of Canada Taxa named by Christian Rudolph Wilhelm Wiedemann {{Syrphidae-stub