How do you lock your recumbent?
You could get some Pitlocks or other secured skewers, and then use a standard U-Lock/Folding lock on your rear stays.  I'm not sure if Pitlocks fit a recumbant properly or if you want to trust your entire bike to them (rather than just the wheels) but it would probably be OK. Also, you could use a U-Lock between the seat and the front fork (possibly with some security bolts instead of standard allen key bolts). Something in that position would probably be quite difficult to remove.