This member of the Fabaceae family was given this name by René Paul Raymond Capuron in 1968. It is found in northern Madagascar, growing in a well drained limestone soil with quite some water and lots of sun. The stem can grow to 60 centimetres in diameter, the entire plant to ten or even fifteen metres in height. The flowers are pale yellow.
The genera name from Greek delos; 'evident' or 'conspicious' and Greek onyx; 'claw' for the long claw of the petals. The species name means "velvet-like, covered closely with short, soft hairs". The flowers by Solofo Eric Rakotoarisoa, Inaturalist.org. A bad photo of the leaves.

