less bicolored). Additionally, Gurney's eagles dwells in forests as well but often tend to occur at slightly lower elevations than Papuan eagles and may be more prone to occurring near varying and less dense habitats. The wedge-tailed eagle and the white-bellied sea eagle are both very range-restricted in New Guinea and frequent drastically different habitats than the Papuan eagle. The more common long-tailed honey buzzard is much smaller than the Papuan eagle, with a different wing shape, a well-streaked underside and wing linings and broadly banded flight feathers and tail. Despite their distinctive appearance, the honey buzzard is not infrequently mistaken for a Papuan eagle in the dense, dark forests. Voice The call of the Papuan eagle is a startlingly loud uumpph or okh, suggesting a very loud hiccup or taut bowstring. Their call is said to carry quite well through the forest. The main call is occasionally followed by a somewhat chicken-like but more loud and powerful buk-buk-buk. Also, a deep resonant bungh-bungh may be uttered at 2-3 second intervals. A high-pitched whining call has also been reported. Pairs may call at dawn and dusk and even call during night. The greater coucal may at times produce a similar call, but has a more musical and descending-type call. Taxonomy The Papuan eagle is the only member of the genus Harpyopsis. Despite its isolated range, the Papuan eagle was once thought to be related to the harpy eagle and the Philippine eagle based on similarities of morphology to these larger, but otherwise somewhat similar forest eagles. However, genetic studies showed that the Philippine eagle is actually derived from the lineage of the snake eagles, so is similar only through convergent evolution. The genetic data, however, showed that the Papuan eagle does appear to possess a highly similar genetic sequence to those of harpy and crested eagle, despite these neotropical species being particularly disparate in range from New Guinea (the crested eagle in particular is fairly similar in size and form to the Papuan, but is of more slender form with less extreme elongation of its legs and tail). Therefore, the Papuan eagle forms a clade with the harpy and crested eagles despite each species being distinct enough to retain their own monotypical genera. Behaviour and ecology The Papuan eagle is an elusive forest dweller. Despite old claims that it soars, even claims that it does so frequently, evidence indicates it