Polyptychus affinis is a moth

Moth

A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

 of the Sphingidae

Sphingidae

Sphingidae is a family of moths , commonly known as hawk moths, sphinx moths and hornworms, that includes about 1,200 species . It is best represented in the tropics but there are species in every region . They are moderate to large in size and are distinguished among moths for their rapid,...

 family. It is known from forest up to 6000 feet (1,828.8 m) from Sierra Leone

Sierra Leone

Sierra Leone , officially the Republic of Sierra Leone, is a country in West Africa. It is bordered by Guinea to the north and east, Liberia to the southeast, and the Atlantic Ocean to the west and southwest. Sierra Leone covers a total area of and has an estimated population between 5.4 and 6.4...

 to the Congo

Congo Basin

The Congo Basin is the sedimentary basin that is the drainage of the Congo River of west equatorial Africa. The basin begins in the highlands of the East African Rift system with input from the Chambeshi River, the Uele and Ubangi Rivers in the upper reaches and the Lualaba River draining wetlands...

, Uganda

Uganda

Uganda , officially the Republic of Uganda, is a landlocked country in East Africa. Uganda is also known as the "Pearl of Africa". It is bordered on the east by Kenya, on the north by South Sudan, on the west by the Democratic Republic of the Congo, on the southwest by Rwanda, and on the south by...

 and western Kenya

Kenya

Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...

.

The length of the forewings is 28–30 mm (1.1–1.2 ) for males. The forewings are grey with a prominent black basal spot, and wavy transverse dark lines. The body is grey with a median blackish streak on the head and thorax. The hindwings are grey with a black streak near the inner margin and one or two black spots near the tornus. Females are larger. They have purplish chocolate forewings, mottled with lighter brown. The hindwings are darker than the forewings. The black inner marginal streak and tornal spots are present.

The larvae feed on Detarium senegalense

Detarium senegalense

Detarium senegalense, commonly known as the Sweet Detar, is a species of flowering plant in the pea family, Fabaceae. This fruit is mostly enjoyed in West Africa. Still a traditional food plant in Africa, this little-known fruit has the potential to improve nutrition, boost food security, foster...

and Albizia

Albizia

Albizia is a genus of about 150 species of mostly fast-growing subtropical and tropical trees and shrubs in the subfamily Mimosoideae of the legume family, Fabaceae. The genus is pantropical, occurring in Asia, Africa, Madagascar, Central, South, and southern North America and Australia, but mostly...

species.