The nape (or hind neck) was ferruginous (rust-coloured), the breast was grey, and it had a black band across the lower throat.

[3][5] In 1844 the German naturalist Hinrich Lichtenstein published J. R. Forster's account of the discoveries made during the journey, including his description of the Tahiti rail.

[4] In 1972 the ornithologist Phillip L. Bruner stated the bird was last recorded on Mehetia about fifty years earlier.

[3] In 2001 the English writer Errol Fuller stated that unlike some other "hypothetical extinct species" only known from old accounts, the Tahiti rail was sufficiently well documented for there to be no doubt that it existed.

In his 1783 description of the Tongan bird (wherein it was named Rallus eucaudata), the English ornithologist John Frederick Miller erroneously gave its locality as Tahiti, which led the Tahiti rail to be regarded as a junior synonym of the extant bird.

The 1844 publication of Forster's description listed the Tongan bird as a variety of the Tahitian species, and similar schemes were suggested by later writers until 1953, when the New Zealand biologist Averil Margaret Lysaght pointed out Miller's locality mistake, which had been overlooked until that point, and kept the two birds separate.

In 1973 the American ornithologist Storrs L. Olson argued that many insular flightless species of rails were descended from still extant flighted rails, that flightlessness had evolved independently and rapidly in many different island species, and that this feature is therefore of no taxonomic importance.

Flightlessness can be advantageous (especially where food is scarce) because it conserves energy by decreasing the mass of flight muscles; the absence of predators (particularly mammalian) and a reduced need for dispersal are factors that allow this feature to develop in island birds.

[15] J. R. Forster stated the Tahiti rail was 9 inches (23 cm) long, which is small for a member of its genus.

The nape (or hind neck) was ferruginous (rust-coloured), the breast was grey, and it had a black band across the lower throat.

[4][16] Forster's original description of the bird follows below, in a translation from Latin published by the English naturalist Walter Rothschild in 1907: Black with white spots or bars; abdomen, throat, and eyebrow white; hind neck ferruginous; breast grey; bill blood-red; iris red.

The mandibles subequal, pointed; the upper slightly curved, with the tip pale fuscous; gape medium.

The middle one almost as long as the Tibia, the side ones of equal length shorter, the back one short, raised from the ground.

[16] Forster's plate (which Fuller described as "rather crude" yet "explicit") became the basis for other depictions of the bird, by artists such as John Gerrard Keulemans (1907), Fenwick Lansdowne (1977), and Hume (2012).

Keulemans' illustration was made for the 1907 book Extinct Birds (before Forster's original had been published) by Rothschild, who pointed out that the legs had been painted too brightly red in the new adaptation, when they should instead have been flesh-coloured.

Its diet appears to have consisted mainly of insects found in grass, and it occasionally fed on copra (coconut meat).

The small, outlying islands off Tahiti also have rats, though there were no cats on Mehetia at the time of Greenway's writing in 1967.

[4] According to Olson, it is possible that hundreds of rail populations have become extinct from islands following the arrival of humans within the past 1500 years.