Originally posted by swanlefitte I think this is a robber fly.
I'm not very good on flies but It is definitely not a robber fly. It looks more akin to a crane fly, but I don't think the legs are quite long enough.
FOLLOWUP: It certainly looks like
Diogmites except for the legs, which look more slender in the specimen you photographed. I came across this reliable way to distinguish robber flies from crane flies: 1) robber fly antennae have three segments; 2) crane fly antennae have at least six segments and are commonly, but not always, plumose. In the images you've posted, especially the second one, the antennae appear to be plumose, but I cannot count the segments.