Chen J., Callac P., Parra L.A., Karunarathan S.C., He M.-Q., Moinard M., De Kesel A., Raspé O., Wixitrassameewong K., Hyde K.D., Zhao R.-L. (2017). Study in Agaricus subgenus Minores and allied clades reveals a new American subgenus and contrasting phylogenetic patterns in Europe and Greater Mekong Subregion. Persoonia 38: 170-196

Abstract: Within Agaricus subg. Minores, A. sect. Minores remains a little-studied section due generally to its
delicate sporocarps often lacking taxonomically relevant morphological characters. To reconstruct the section,
using the recent taxonomic system based on divergence times, and to evaluate the species diversity of A. sect.
Minores in the Greater Mekong Subregion, 165 specimens were incorporated in phylogenetic analyses. A dated
tree based on nuclear ITS, LSU and tef1-α sequence data allowed us to better circumscribe A. subg. Minores and
to propose a new subgenus, A. subg. Minoriopsis, which is only known from tropical and subtropical regions of the
Americas. A larger tree based on ITS sequences indicated that, with 81 phylogenetic species, the reconstructed
section Minores is now one of the largest sections in the genus. Within A. subg. Minores, a new section, A. sect.
Leucocarpi, and eleven new species are described from the Greater Mekong Subregion. Thirty-eight species of
A. sect. Minores from this region of Asia were distributed in multiple clades that successively diverged over the past
24 million years. In contrast, species reported from Europe mostly grouped in a single non-tropical clade, suggesting
a major species diversification following the middle Miocene climatic optimum.