I agree with you ID as L. erythrocephalus Max. I've been curious about this genus for a while, so I downloaded this recent, very good revision. Although I've not gone through it in great detail (yet!), only L. erythrocephalus matches your large ant with a fully red head. Here's the link - you might find it interesting too: http://antwiki.org/wiki/images/1/14/Lucky_%26_Ward_2010.pdf