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Bright Oak Blue (Arhopala madytus)

Bright Oak Blue
Underside. (Daintree NP, QLD, 30 / 12 / 2005)

Appearance: Upperside bright iridescent blue. Underside ground colour dark purple with several dark markings. Very similar to other species in the genus Arhopala.
Wingspan: 4.2 cm
Season: Several generations all around the year.
Range: Eastern QLD, along the central and northern coast all the way up to Cape York.
Habitat: Edges of coastal rainforest and gallery forest.


The Bright Oak Blue is a spectacular species due to its bright, iridescent blue colour on the upperside of the wings. Unfortunately, the butterflies normally have their wings closed, thus displaying only their dark underside. They can be found along the edges of rainforest and gallery forest in coastal areas of eastern QLD. The larvae live in close symbiosis with the Green Tree Ant (Oecophylla smaragdina).

There are two very similar similar species along the east coast of QLD, the Purple Oak Blue (Arhopala centaurus) and the Shining Oak Blue (Arhopala micale). The former has the underside ground colour much lighter, whereas the latter has a slightly different pattern of dark markings on the underside compared to the Bright Oak Blue.

Additional Photos

Bright Oak Blue
Underside. (Edge Hill, QLD, 11 / 11 / 2012)