After we left the Sarapiqui area, our guide recommended a roadside stop at an area where he had frequently seen the Black-crested Coquette (a species of hummingbird). While waiting for them to appear, several of us took some shots of some gorgeous dragonflies. I'm not sure if this is the male or female, but there was another one nearby, whose body was somewhat more orange. I have several shots taken a little bit later, as they mated. Note: This identification is courtesy of James A. Christenson, who was kind enough to check it against a book he recently acquired, and email me. His excellent website can be seen here.
(We only had a couple of very quick sightings of the Black-collared coquette, and I did manage to get a decent shot. But it was somewhat obscured by vegetation, and I haven't posted it here.)