Porphyrio is the Latin for "swamphen", and alleni, like the English name, commemorates British naval officer Rear-Admiral William Allen (1792–1864).

Remarkably, this apparently weakly flying bird is not only the only species with a purely sub-Saharan African range to have reached Great Britain, but has done so twice.

The Allen's gallinule has a short red bill, greenish back and purple upperparts.

They have red legs with long toes, and a short tail which is white with a dark central bar underneath.

Allen's gallinules are very secretive in the breeding season, particularly in the dense swamps they favour, and are mostly heard rather than seen.