Several species of silkmoths are involved in this form of sericulture. They belong to the genera Anaphe and Epanaphe (Gaede 1928). Some entomologists consider these genera to belong to the family Thaumetopoeidae (Pinhey 1979), the processionary caterpillars, but others consider that group to be a subfamily (Thaumetopoeinae) of Notodontidae. The caterpillars construct communal bagnests and these are the source of the silk. They have been greatly over-exploited in the 20th century, which coupled with deforestation, resulted in this type of sericulture becoming a thing of the past. Today the silk is substituted by kugu, which is cotton that has been dyed to resemble the wild silk. Garments made of the prestigious silk (and now the brown-dyed cotton) have great ceremonial significance in Yoruba culture, and the pieces are worn primarily on special occasions such as weddings, funerals, etc. Collectors seeking genuine sanyan silk must obtain vintage (pre-1970) or antique pieces, which are occasionally offered on the internet. Some of the foodplants commonly cited for the caterpillars include wild coffee (Bridelia micrantha), tamarind (Tamarindus indica), and obeche (Triplochiton scleroxylon). The obeche is one of the most important timber trees in West Africa.