The Callaeidae (sometimes called Callaeatidae), also known as New Zealand wattlebirds and informally, though inaccurately, referred to as wattled crows, comprise a family of passerine birds unique to New Zealand. There are five species across three genera within this family, though the South Island kokako is critically endangered and the huia is extinct. These birds, which range from 26–38 cm in length, are ground-dwelling songbirds with strong legs, featherless wattles behind the bill, and rounded wings that grant them limited flight ability. Callaeidae occupy dense forests, feeding on insects, and they are monogamous, maintaining permanent territories. The family, which shows remnants of an early wave of passerines in New Zealand, is closely related only to the stitchbird. The family consists of the living North Island kokako (Callaeas wilsoni), North Island saddleback (Philesturnus rufusater), and the extinct South Island kokako (Callaeas cinereus) and huia (Heteralocha acutirostris), with the South Island saddleback (Philesturnus carunculatus) not sampled in the recent study.