I plan to try to sort this out, for my own reference and to help others.
Meanwhile I'll continue to post my photos as I take them.
This one is Lycaena edna, Maui's Copper - a butterfly of the family Lycaenidae.
The wingspan is 24–35 mm. Adults are on wing from October to April. The females have broad single veins on the wings, while the males have double vein markings.
The larvae feed on Muehlenbeckia species.