These are S.A. locale-the prettiest of the species.
You should be able to find ruschenbergerii on your island. They are much darker and less heavily patterned than the Costa Rican ruschis for some reason-but still attain the great size they are famous for.
Annulatus is also endemic to Panama; have no idea about your island. They are found on Barro Colorado Is on the isthmus so they may be a possibility as well. I would be very curious to see photos of whatever you find on the island.
Ungaliophis is also found in Panama, btw.

Best regards,
Jeff
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Jeff Murray
www.boa-subspecies.com
http://s352.photobucket.com/home/boidsonly/allalbums