Tim,
There's a few ways you can do this, as always.
The delete row/feature snippet shows an example of using a row cursor within an edit operation callback. This would be used if the feature class/table wasn't in the map.
You can also use a simple edit operation delete with a list of oids from a queryfilter.
QueuedTask.Run(() =>
{
var streams = MapView.Active.Map.GetLayersAsFlattenedList().FirstOrDefault(l => l.Name == "Streams") as FeatureLayer;
QueryFilter queryFilter = new QueryFilter { WhereClause = "FType = 460" };
var selection = streams.GetTable().Select(queryFilter, SelectionType.ObjectID, SelectionOption.Normal);
var op = new EditOperation();
op.Name = "Delete with queryfilter";
op.Delete(streams,selection.GetObjectIDs());
op.Execute();
});
You could also iterate through a rowcursor (table.search) to get the OID's and feed those into delete.