Sequestrate Lactarius species from tropical Africa: L-angiocarpus sp nov and L-dolichocaulis comb. nov

Lactarius angiocarpus sp. nov. is described from miombo woodlands in Zambia. It is the third sequestrate representative of the Russulaceae described from tropical Africa. Morphological characters and DNA sequence data support its placement in Lactarius subgen. Plinthogali. Molecular kinship analyses confirm a multiple origin of sequestrate Russulaceae spp. As none of the previously sequenced sequestrate Russulaceae spp. has been assigned to the Plinthogali clade, the placement of L. angiocarpus indicates an additional point of origin of derivative sporocarp types within the Russulaceae. Within the same subgenus, another tropical African sequestrate species, L. dolichocaulis comb. nov. (syn. Arcangeliella dolichocaulis) is recognized.