The delineation of natural areas in New Zealand: Former faunal areas: some sub-fossil evidence
Any discussion of former faunal areas based on the distribution of fossil or sub- fossil bones is complicated when those bones are of various geological ages. Nevertheless, study of the regions in which the genera and species of moa are found makes possible some tentative conclusions.
The evidence is unevenly distributed because some areas—the best sources are caves, swamps and sandhills—are better suited to the preservation of bones, or have been better explored. The South Island Megalapteryx didinus (Owen) ranged down the west coast to Inangahua Junction, from Takaka to coastal Marlborough, down the East Coast to Southland and the Te Anau-Lake Wakatipu area. Megalapteryx benhami Archey is known only from the Nelson area.
Anomalopteryx didiformis (Owen) has virtually the same South Island distribution as Megalapteryx, but not as far west in Otago and Southland. In the North Island it is not uncommon in Wellington district, ranging up the east coast to Gisborne, is found at Coromandel Peninsula, Whangarei, up the west coast, and in southern Auckland. The smaller Anomalopteryx oweni (von Haast) is most common in North Auckland, but is known from Te Aute swamp (Hawkes Bay), Martinborough (Wellington) and around Wanganui. As Euryapteryx and Zelornis can only be separated if the skull is present, possibly some Euryapteryx gravis (Owen) records may be of Zelornis haasti (Rothschild), and some Euryapteryx tane Oliver may be of Zelornis exilis (Hutton).