René Lesson first described the species in 1828 from a specimen collected in the Bay of Islands four years earlier, using the binomial name Icterus rufusater.

[4][5] The specific name rufusater refers to the saddleback's plumage – a combination of the Latin words rufus 'reddish-brown', and ater 'black'.

[3] Today they are generally considered to be separate species, with the North Island saddlebacks having the binomial Philesturnus rufusater.

[8] The plumage of North Island saddlebacks is mostly black apart from the saddle, rump, and tail coverts, which are chestnut.

[3] Males tend to be heavier (80 g) than females (69 g), and possess longer bills and larger wattles.

[9] The diet of North Island saddlebacks mostly consists of insects and other invertebrates, berries, and nectar.

[3][9] Introduced mammalian predators, particularly brown rats, were the primary cause of the North Island saddleback's extinction from mainland New Zealand.

North Island saddlebacks appear to be capable of co-existing with some predators such as the kiore, possibly because they have had a longer history of cohabitation than with brown and black rats.