Lactifluus gymnocarpoides (Ubutuntutuntu)
Lactifluus gymnocarpoides is an edible species of milk cap fungus that form relationships with the roots of certain tropical legume trees and is widespread in tropical Africa.
Lactifluus gymnocarpoides (Photo: Annemieke Verbeken)
Lactifluus gymnocarpoides (Verbeken) Verbeken
Ubutuntutuntu (eastern Burundi), kpahu alama (crackling with milk, Nagot), dikookon (Ditammari), katadji (put on potash for preparation, fulfuldé), geingi (Bariba)
Widespread and not yet evaluated according to IUCN Red List criteria.
Miombo woodland, riparian forest, dry coastal forest, savannah woodland, riverine forest, semi-evergreen forest.
About this species
Lactifluus is a genus of fungus commonly known as milk caps, as they often exude latex (milky fluid) when cut. Until recently they were classified as Lactarius. Lactifluus is well represented in tropical Africa and Madagascar with 58 accepted species, although the full count is probably more than 80.
The genus was recently split from Lactarius after it was demonstrated that Lactarius and Russula (Russulaceae) are paraphyletic (ie some but not all members of the group are descended from the same common ancestor) and that they should be divided among four distinct genera: Russula, Lactarius, Lactifluus and Multifurca.
Lactarius phlebophyllus ss. Morris (1990)
Geography and distribution
Lactifluus gymnocarpoides has been found in Benin, Burundi, Democratic Republic of the Congo, Guinea, Madagascar, Malawi, Senegal, Tanzania, Zambia and Zimbabwe.
The cap (pileus) is thick and usually measures 6–9 cm in diameter. The outer skin (pellis) is dry and smooth or finely felty, wrinkled to crackling. It is greyish orange to orange when young, becoming light orange later. The latex is not abundant, white and mild to astringent.
Microscopic features used in Lactifluus identification include morphology (especially ornamentation) of the spores and anatomy of the pileipellis (uppermost layer of the fruiting body).
The symbiotic relationship with its host plant
Lactifluus gymnocarpoides is a species of ectomycorrhizal fungus, meaning it must associate with the roots of its host plants in order to develop and survive.
Ectomycorrhizal fungi forge symbiotic relationships with their hosts by forming a sheath around the root tips of their hosts. The fungus takes organic compounds from the plant and in return provides the plant with water and nutrients absorbed from the soil. Other benefits to the plant may include protection against herbivores and resistance to toxins and pathogens.
Ectomycorrhizal relationships are common in both temperate and tropical forests. All members of one group of tropical legumes, the Berlinia clade (such as Isoberlinia doka, Gilbertiodendron dewevrei and Berlinia razzifera), are thought to form ectomycorrhizal relationships with fungi. Lactifluus gymnocarpoides has also been recorded in Tapia (Uapaca bojeri) woodland in Madagascar.
Association with legumes
Ectomycorrhizal symbiotic relationships have been recorded between Lactifluus gymnocarpoides and Isoberlinia doka, I. tomentosa, Anthonotha crassifolia and Brachystegia bussei (all species in the Berlinia clade of the family Leguminosae).
Threats and conservation
Lactifluus gymnocarpoides is considered widespread in tropical Africa and not threatened.
Lactifluus gymnocarpoides is eaten in rural areas in eastern Burundi, Tanzania and Benin. It is a popular food in some localities and can be harvested in large quantities, up to 100 kg per hectare per year.
This species at Kew
Preserved specimens of Lactifluus gymnocarpoides from Malawi and Zambia are maintained in the Kew Mycology Herbarium and, although not accessible to the general public, are available for study by researchers worldwide.
Buyck, B., Hofstetter, V., Eberhardt, U., Verbeken, A. & Kauff, F. (2008). Walking the thin line between Russula and Lactarius: the dilemma of Russula subsect. Ochricompactae. Fungal Diversity 28: 15-40.
Morris, B. (1990). An annotated check-list of the macrofungi of Malawi. Kirkia, 13: 323-364.
Petersen, R. H. (1977). Some brief reflections on C.H. Persoon. Kew Bulletin 31: 695-698.
Van Rooij, P., De Kesel, A. & Verbeken, A. (2003). Studies in tropical African Lactarius species (Russulales, Basidiomycota) 11. Records from Benin. Nova Hedwigia 77: 221-251.
Verbeken, A. (1995). Studies in tropical African Lactarius species. 1. Lactarius gymnocarpus Singer ex R.Heim and allied species. Mycotaxon 55: 515-542.
Verbeken, A. & Walleyn, R. (2010). Fungus Flora of Tropical Africa Volume 2: Monograph of Lactarius in Tropical Africa. National Botanic Garden of Belgium, Meise.
Kew Science Editor: Malin Rivers
Kew contributors: Martin Bidartondo
Copyediting: Nicola Merrett
Kew would like to thank the following contributors: Annemieke Verbeken
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