Adzebill

The adzebills are two species of gruiform birds belonging to the genus Aptornis, the sole member of the extinct family Aptornithidae, which were endemic to New Zealand. The species were divided between the North and South islands of the country, with Aptornis otidiformis being the North Island adzebill, and Aptornis defossor being the South Island adzebill. Additional material from the Saint Bathans fauna may represent a third species.

==Taxonomy== Adzebills were first scientifically described by biologist Richard Owen in 1844, who mistook them for a small species of moa; the type species was initially named Dinornis otidiformis with the specific epithet referring to its comparable size with the great bustard (Otis tarda; otis + formis). Later on, the specimens' distinction were recognised, and so the genus Aptornis was erected to accommodate them; Aptornis is noted to be a syncope of Apterygiornis, an apparent allusion to the genus Apteryx. The alternate spelling Apterornis was coined a week earlier, though it was considered a likely typographical error and was not coined by nor ever used by Owen; a 1997 ICZN ruling rendered it invalid and conserved Aptornis, rendering it the valid name for this taxon.