Named after Sir Jahleel Brenton, who declared Knysna a harbour in 1818, the area is home to the endangered Brenton Blue butterfly.
Three species are recognized, D. pulchra Hoeg 1930 (from the Bloukrans River in the Knysna district, Ceres Subgroup, Lower Bokkeveld Group), D. alfreda Plumstead 1967 (Port Alfred, Weltevrede Subgroup, Lower Witteberg Group) and D. maraisia Plumstead 1967 (Howisons Poort, Witpoort Sandstone, Middle Witteberg Group).
Knysna National Lake Area is a part of the Garden Route National Park in South Africa.
The southern limit is at Cape St. Francis, east of Port Elizabeth in the Eastern Cape Province, where the KwaZulu-Cape forests transition to the Knysna-Amatole montane forests.
Maerua cafra (DC.) Pax is a small Southern African tree belonging to Capparaceae, the caper family, occurring eastwards along the coast from Knysna, then further inland and northwards through KwaZulu-Natal and Swaziland to the Transvaal, southern Mozambique and southern Zimbabwe.
The family emigrated from Stavanger, Norway to Knysna, South Africa in 1869, and founded the company Thesen and Company.
Psychotria capensis (Eckl.) Vatke is a Southern African evergreen shrub or small tree occurring along the east coast from Knysna through the Eastern Cape and KwaZulu-Natal, Mpumalanga, Northern Cape, Mozambique and Zimbabwe.
Graham spent nine months in South Africa, calling on ports along the southern edge of the continent including East London, South Africa, Port Elizabeth, Plettenberg Bay, Knysna, Stilbaai, Struisbaai, Gordon's Bay and finally Cape Town.
James Bowie, the King's Botanical Collector, first collected specimens and seeds of this plant in 1818 near Knysna on the estates of George Rex and sent these to Kew, asking that the plant be named after the legendary Rex.
Thomas married Caroline Rex the daughter of the founder of Knysna, George Rex.
The Dark Grass Blue or African Grass Blue (Zizeeria knysna), is a species of blue butterfly found in Africa, on Cyprus and the Iberian Peninsula.