Lactifluus bicapillus (Russulales, Russulaceae), a new species from the Guineo-Congolian rainforest

Abstract

The milkcap genus Lactifluus is one of the most common ectomycorrhizal genera within Central African rainforests. During a field trip to the Dja Biosphere Reserve in Cameroon, a new Lactifluus species was found. Molecular and morphological analyses indicate that the species belongs to LactifluussectionXerampelini and we formally describe it here as Lactifluusbicapillussp. nov.

A short story of nearly everything in Lactifluus (Russulaceae)

“…However, the genus also appears to be well-represented in South America, as new species are being discovered since more South American habitats are being explored ( Henkel et al 2000 , Miller et al 2002 , Smith et al 2011 , Sá et al 2013 , Sá & Wartchow 2013 , Crous et al 2017 , Delgat et al 2019 , Delgat et al 2020 , Duque Barbosa et al 2020 ), and the majority of the proposed South American Lactarius species turns out to belong in Lactifluus ( Pegler & Fiard 1979 , Singer et al 1983 , Miller et al 2002 ). Since 2010, 78 new Lactifluus species have been described: 34 from Asia ( Stubbe et al 2012a , Van de Putte et al 2012 , Wang et al 2012 , Wang et al 2015 , Morozova et al 2013 , Latha et al 2016 , Li et al 2016 , Uniyal et al 2016 , Zhang et al 2016 , Das et al 2017 , Hyde et al 2017 , Song et al 2017 , De Crop et al 2018 , Liu et al 2018 , Song et al 2018 , Bera & Das 2019 , Dierickx et al 2019a , b , Phookamsak et al 2019 ), 16 from Africa ( De Crop et al 2012 , Maba et al 2014 , Maba et al 2015a , b , De Crop et al 2016a, b , De Crop et al 2019 , Delgat et al 2017 , De Lange et al 2018 ), 20 from the Neotropics ( Miller et al 2012 , Montoya et al 2012 , Sá et al 2013 , Sá &...…”

“… Dierickx et al (2019b) dismiss the idea that these cells represent basidioles or cystidia. They are known to occur in a handful of species ( Delgat et al 2017 , De Crop et al 2019 , Dierickx et al 2019b ), but due to their unremarkable shape and content, they might be overlooked and thus more common than currently known.…”

“…A. Thin-walled, cylindrical, and septate sterile elements, sometimes with clamp-like bulges under the septum, of Lf. bicapillus (EDC 12-169, adapted from De Crop et al 2019 ). B. Cylindrical, septate, and slightly thick-walled sterile elements of the hymenium in Lf.…”

Updated taxonomy of Lactifluus section Luteoli: L. russulisporus from Australia and L. caliendrifer from Thailand

“…Even though this type of cell is frequently present in Lactifluus (pers. observations), these cells are only rarely reported in species descriptions (De Crop et al 2019;Delgat et al 2017), probably often being dismissed as basidioles and/or of limited taxonomic value. This problem presented itself during the description of the two new species and a consensus between the authors of this paper was pursued.…”