Previous plant

Dioscorea cayenensis

Next plant

I fail to see the double "n".

Author:  J.B.A.P. de Monnet de Lamarck, 1789
Origin:  Benin, Burkina, Cameroon, Central African Republic, Congo, Gambia, Ghana, Guinea, Guinea-Bissau, Gulf of Guinea Island, Ivory Coast, Liberia, Mali, Niger, Nigeria, Senegal, Sierra Leone, Togo (South Africa, Africa, Caribbean Islands)
Soil:  Clay - Organic
Water:  Maximum
Sun:  Medium - Maximum
Thickness:  10 (20) Centimetres
Height:  12 Metres
Flower:  White
Propagate:  Seeds/Roots
Names:  Yellow Yam
Synonyms:  Dioscorea cayennensis: See below*

This member of the Dioscoreaceae family was given this name by Jean Baptiste Antoine Pierre de Monnet de Lamarck in 1789. It is found in central Africa (and introduced to Brazil and the Caribbean), growing in a clayish soil with organic matter, receiving plenty of water and some to lots of sun. The caudex can grow to ten or even twenty centimetres in diameter, the entire plant to twelve metres in height. The flowers are white.

The leaves are extremely  varied, from deeply cordate to almost orbicular.

Dioscorea is named after Pedianos Dioscorides, a Greek physician if the 1st century A.D. The species is named after Cayenne, the capital of French Guiana.

*Strangely enough, MoBot have both spellings, both referring to Encyclopédie Méthodique, Botanique 3: 233. 1789. However, I fail to see the double "n".