Unknown Dragonfly from the Galapagos

Here are three shots of male and female of a Tramea species dragonfly from the Galapagos Islands in July, 2003. Several experts have examined these images; one believes that the species is Tramea calverti while the other thinks it is Tramea cophysa. So far I have not been able to resolve this. This species was not uncommon and I saw it on several of the islands visited. Any more thoughts on the ID of this dragonfly will be appreciated.