Marsh or Snail-killing Flies (family Sciomyzidae) are very common around wetlands. According to Flies: The Natural History and Diversity of Diptera by Stephen A. Marshall "most sciomyzids occur in moist to aquatic environments, where they develop as parasitoids or predators of aquatic or semiaquatic snails or sphaeriid clams such as fingernail clams." According to Bugguide.net over two hundred species in twenty genera exist in North America.
The Marsh Flies I most often encounter are of the genus Sepedon. This is a very distinctly-shaped fly, foward-thrusting antennae, a long face and grasshopper-like rear legs. Most often, this fly perches upside-down on grass stems and the stalks of other vegetation near water.
Over the last two days, I've encountered two additional kinds of Marsh Fly. Yesterday, the tiny Pherbellia sp. was observed on a dandelion flower next to a catchment pond. Today, the spot-winged Dictya was observed on a blade of grass along a small, temporary rivulet.
Orbweaver
St Olaf Natural Lands
Northfield, Minnesota
TL=2mm
Nomad Bees
Lashbrook Park
Northfield, Minnesota
Crane Fly
St Olaf Natural Lands
Northfield, Minnesota
Marsh Fly
St Olaf Natural Lands
Northfield, Minnesota
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Im not sure what genera we have locally but the ones Im used to seeing look very interesting, quite angular in form and posture. They are pretty willing (indifferent) photographic subjects, hardly moving unless prodded.
I did not know their history but thought their name had a nice sound to it. The history makes them even more fascinating.
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