[3] The spot-flanked gallinule weighs between 154 and 225 grams, with an average length of 28 cm, often described as a small waterfowl-like bird.

[4][5] Its head, chin, neck and breast feathers are a slate gray, contrasting with the black forehead and crown, extending to the top of the nape.

[4] Juveniles do not have any contrasting plumage and are typically entirely black before developing brown feathers followed by the other distinctive mature features.

Its iris changes from black as juvenile, to different shades of brown to its eventual, mature, vibrant red color.

[3][6] Previous research dictated that this difference meant it belonged in Genus Porphyrio but recent research on chromosomal data has shown very few similarities to P. porphyrio and instead, closely related to Gallinula chloropus, describing the spot-flanked gallinule into Genus Gallinula.

[5] The spot-flanked gallinule has a general distribution across South America although larger populations can be found within Brazil, Argentina, Chile, Paraguay and Uruguay.

[2] Both males and females partake in the construction and caring of the nest, with only one breeding pair found per body of water.

The developed chicks will be fed and protected by the parents for the next 50 days but they have full swimming and diving capabilities within a few hours of hatching.