Lactifluus is a monophyletic genus of ectomycorrhizal fungi with about 200 described species classified in four subgenera: L. subg. Gymnocarpus, L. subg. Lactariopsis, L. subg. Lactifluus, and L. subg. Pseudogymnocarpus. Currently L. subg. Lactariopsis is considered monophyletic with approximately 57 species described and classified in four sections: Albati, Edules, Lactariopsis, and Russulopsidei. There are few species of L. subg. Lactariopsis described from the Neotropical region, however local mycologists commonly collect specimens of this subgenus during their mycological surveys. The goals of the present study are to evaluate the phylogenetic and morphological relationships of the species from L. subg. Lactariopsis found in Brazil, to contribute to the knowledge of Lactifluus in Neotropical ecosystems by describing a new section in this subgenus and two new species from Brazil, and to document L. neotropicus as a new record from Brazil. Based on morphological and phylogenetic evidence we propose Lactifluus sect. Neotropicus as a new section and Lactifluus catarinensis and L. marielleae as two new species in this section. We provide a key to the species of L. sect. Neotropicus, which is shown to be a monophyletic group of Neotropical species within L. subg. Lactariopsis. The most striking characteristic of several species in L. subg. Lactariopsis is the secondary angiocarpic development, not present in the other subgenera. Species with a secondary veil can be found in two lineages that diversified more recently than the rest of the genus: L. sect. Lactariopsis and L. sect. Neotropicus. Species that show morphological affinities with the two new species in L. sect. Neotropicus described here are commonly found and we expect a greater diversity to be revealed of this section in the Neotropical region.

中文翻译：

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一个新的部分，Lactifluus 部分 Neotropicus (Russulaceae)，以及来自巴西大西洋森林的两个新 Lactifluus 物种

Lactifluus 是外生菌根真菌的单系属，有大约 200 个描述的物种，分为四个亚属：L. subg。Gymnocarpus, L. subg. Lactariopsis, L. subg. Lactifluus 和 L. subg。Pseudogymnocarpus。目前 L. subg。Lactariopsis 被认为是单系的，大约有 57 个物种被描述并分为四个部分：Albati、Edules、Lactariopsis 和 Russulopsidei。L. subg 的种类很少。Lactariopsis 从新热带地区描述，然而当地真菌学家通常在他们的真菌学调查中收集这个亚属的标本。本研究的目的是评估 L. subg 物种的系统发育和形态关系。在巴西发现的乳杆菌 通过描述该亚属的一个新部分和来自巴西的两个新物种，为新热带生态系统中 Lactifluus 的知识做出贡献，并将 L. neotropicus 记录为来自巴西的新记录。基于形态学和系统发育证据，我们提出乳杆菌属。Neotropicus 为新科，Lactifluus catinensis 和 L. marielleae 为该科的两个新种。我们提供了 L. sect 物种的钥匙。Neotropicus，它被证明是 L. subg 内的一个新热带物种的单系群。乳杆菌。L. subg 中几个物种最显着的特征。Lactariopsis 是次生的 angiocarpic 发育，在其他亚属中不存在。具有次级面纱的物种可以在两个谱系中找到，这些谱系最近比该属的其他部分更加多样化：L. sect。Lactariopsis 和 L. sect。新热带鱼。与 L. sect 中的两个新物种表现出形态亲缘关系的物种。此处描述的 Neotropicus 很常见，我们预计在新热带地区的这一部分会显示出更大的多样性。