The Rodrigues rail is believed to have become extinct in the mid-18th century mainly because of predation by introduced cats and hunting.

In 1848, the English zoologist Hugh Edwin Strickland called attention to a bird mentioned in the French traveller François Leguat's 1708 memoir A New Voyage to the East Indies about his stay on the Mascarene island of Rodrigues from 1691–93.

[6][7] Milne-Edwards connected Leguat's account with three bones (a sternum, a tarsometatarsus, and a fragmentary skull) found in caves of the Plaine Corail region, Rodrigues.

[6][5][8] The name Erythromachus was incorrectly explained as referring to the Erythraean sea by the American ornithologist Charles Wallace Richmond in 1908.

[8] In 1875, A. Newton also identified a reference to the bird in the 1725–26 account of the French traveller Julien Tafforet, Relation de l'Ile Rodrigue, which had recently been rediscovered.

[11] In 1921, the American linguist Geoffroy Atkinson questioned the bird's existence, in an article that doubted the veracity of Leguat's memoir.

[3] Today, it is widely accepted that Leguat's memoirs represent credible observations of local birds in life.

[16] More subfossils have since been discovered, including an associated but incomplete skeleton with a complete skull and jaws found in Caverne Poule Rouge in 2005.

Based on geographic location and the morphology of the nasal bones, Olson suggested that they were related to the genera Gallirallus, Dryolimnas, Atlantisia, and Rallus.

According to the British researchers Anthony S. Cheke and Julian P. Hume in 2008, the fact that the red rail lost much of its feather structure indicates it was isolated for a long time.

Hume suggested that the two rails were probably related to Dryolimnas, but their considerably different morphology made it difficult to establish how.

In general, rails are adept at colonising islands, and can become flightless within a few generations in environments without predators, yet this also makes them vulnerable to human activities.

The cranium of the Rodrigues rail was slightly elongated, convex in every direction, and compressed from top to bottom in side-view.

The premaxilla that comprised most of the upper bill was long, shallow in side-view, with a narrow nasal bone, and its total length was almost 60% longer than the cranium.

The humerus (upper arm bone) was very small, its shaft was curved from top to bottom, and it ranged from 45 to 50 mm (1.8 to 2.0 in).

The radius and ulna (lower arm bones) were short, and the latter was and strongly arched from top to bottom, ranging from 37 to 42 mm (1.5 to 1.7 in).

[5][16] The Dutch ornithologist Marc Herremans suggested in 1989 that the Rodrigues and red rails were neotenic, with juvenile features such as weak pectoral apparatuses and downy plumage.

[22][20] The Rodrigues rail was first recorded by Leguat in his 1708 memoir, and his account of the bird reads as follows: Our 'gelinotes' are fat all the year round and of a most delicate taste.

The rails would have fattened themselves seasonally, but at other times of the year, they probably fed on snails and other invertebrates, as well as scavenging sea bird colonies.

The Rodrigues rail probably fed on worms, such as Kontikia whartoni and the now extinct Geonemertes rodericana, by probing leaf-litter or rotting wood.

For at least a century the Rodrigues rail may have coexisted with rats, which were perhaps introduced by a group of sailors from a Dutch ship marooned there in 1644.

Though rats were well established and numerous by the time Leguat and Tafforet stayed on the island, the rails also remained common, perhaps due to their aggressive nature.

[8]The French began settling Rodrigues in 1735 (to supply Mauritius with tortoise meat), and Hume and the British ornithologist Michael Walters stated in 2012 that this must have taken a toll on the rails through hunting and deforestation, but their rapid disappearance was probably caused by cats introduced to control the rats around 1750, and the species may have gone extinct within a decade.

[10][8] Cheke responded in 2013 that there was no deforestation at the time, the species appears to have survived the rats, and that cats were the main culprits, assisted by hunting.