A black rather gangling fly. Slow and rather lumbering flight
No interactions present.
It does look like marci, but female leucopterus is very similar, so without a good view of wing venation or fore tibial spurs, it's tricky to be certain. Both are flying at the moment.
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Lat/Lng: 51.948, 1.0605
OS grid ref: TM104321
Seawall to the River Stour estuary running between The Skinners P.H.,Manningtree and Cattawade. An excellent place for insects in the Spring/Summer and birds Autumn?winter. Many wild flowers, reed beds and small shrubs.