Lactarius Subg Research Articles

Morpho-molecular analyses and scanning electron microscopy reveal two new species of genus Lactarius from the northwestern Himalaya, India.

One of the largest subgenera of the genus Lactarius, Lactarius subg. Russularia is abundant in the forests of the Himalayas. This article proposes Lactarius crassostipes sp. nov. and Lactarius flavocorpus sp. nov. under the L. subgenus Russularia. It includes comprehensive macro- and micro-morphological descriptions, scanning electron microscopy (SEM) micrographs, drawings, and comparisons with related species. The taxa's novelty is validated using phylogenetic analyses based on nrITS. RESEARCH HIGHLIGHTS: SEM and subsequent nrITS-based molecular phylogeny revealed two novel species (L. crassostipes and L. flavocorpus) of the genus Lactarius subg. Russularia. To further characterize the size, form, and ornamentation of these novel species' basidiospores, SEM analysis is an additional tool. In L. crassostipes "crasso" means thick and "stipes" indicates stipe. In contrast to L. flavocorpus, where "flavocorpus" refers to the golden yellow fruiting body, the name alludes to its unique thick stipe. L. crassostipes sp. nov. and L. flavocorpus sp. nov have been collected from the coniferous and broad-leaved forests of Union Territory of Jammu and Kashmir, India, respectively. The diagnostic characteristics, habit, habitat, and similarities to related species are given.

Lactarius bhaderwahensis: a new species of Lactarius subg. Plinthogalus (Russulaceae) from coniferous forests of Northwestern Himalayas, India

Lactarius bhaderwahensis sp. nov. is here described as a new species from coniferous forests of Jammu. Morphological and molecular (nrITS) sequence data placed the new species within Lactarius subg. Plinthogalus. It is characterized by its basidiocarps with brown to cinnamon‐brown to greyish brown pileus, abundant white latex that turns light orange to greyish orange, globose to subglobose basidiospores with winged ornamentations having ridges forming a broken reticulum, trichopalisade pileipellis and occurrence under Abies pindrow. A detailed macro‐ and micro‐morphological description along with anatomical photographs, line drawings, phylogenetic analysis and comparisons with similar species are provided.

Russulaceae of the Pakaraima Mountains of Guyana. IV. New species forming a distinct lineage of Lactarius subg. Plinthogalus

ABSTRACT The Neotropics have recently emerged as an important region for studies of tropical ectomycorrhizal (ECM) fungi. Specific neotropical areas with high ECM host tree densities have ECM fungal diversities rivaling those of higher-latitude forests. Some forests of the Guiana Shield are dominated by endemic ECM trees of the Fabaceae, including species of Dicymbe (subfam. Detarioideae), Aldina (subfam. Papilionoideae), and Pakaraimaea (Cistaceae). One of the most species-rich ECM fungal families present in each of these systems is Russulaceae. Long-term sampling in forests in Guyana’s Pakaraima Mountains has revealed a number of species of the Russulaceae genera Lactarius, Lactifluus, and Russula. In this study, we document a previously unknown, distinct lineage of Lactarius subg. Plinthogalus containing eight species from the Guiana Shield. Here, we describe five of these species from Guyana as new to science: Lactarius humiphilus, Lactarius mycenoides, Lactarius guyanensis, Lactarius dicymbophilus, and Lactarius aurantiolamellatus. Morphological descriptions, habit, habitat, and known distribution are provided for each new species. Sequence data for the barcode internal transcribed spacer (ITS) locus are provided for types and most other collections of the new taxa, and a molecular phylogenetic analysis based on the ITS, 28S, and RPB2 (second-largest subunit of the RNA polymerase II) loci across the genus Lactarius corroborates their morphology-based infrageneric placement. The discovery of this lineage changes our insights into the biogeography and evolutionary history of Lactarius subg. Plinthogalus.

Lactarius pseudoaurantiozonatus (Russulales), A New Species of Lactarius subgenus Lactarius from China

Lactarius pseudoaurantiozonatus, belonging to Lactarius subg. Lactarius, is proposed as a new species from Anhui Province, China based on detailed morphology and molecular analyses (nrITS) region. Lactarius pseudoaurantiozonatus, is characterized by a pale yellow to orange-yellow, zonate pileus, subglobose to broadly ellipsoid basidiospores which measure 5.5–7.9 × 4.5–6.5 μm, white latex which quickly turns olive-yellow, indistinct odor and burning-acrid taste.

A New Species of Lactarius subg. Lactarius (Russulaceae) from Baiyun Mountain, China

A new species of Lactarius subg. Lactarius from Baiyun Mountain, Guangdong Province in southern China is described based on phylogeny of the internal transcribed spacer (ITS) and morphological analyses. Lactarius baiyunensis sp. nov. is characterized by a light brown to white, azonate or inconspicuously zonate pileus, irregular brownish spots on the stipe, latex unchanging in color, small globose to subglobose basidiospores with pronounced ornamentation, absence of cheilocystidia and an ixotrichoderm for a pileipellis. The new species is presented with illustrated description, and comparisons of morphology and phylogeny are made with closely related species.

Morphology and Molecular Phylogeny Reveal Three New Records of Wild Mushrooms from India in <i>Lactarius</i> Subgenus <I>Russularia</i>

This paper is a contribution to the Indian mycobiota. During a routine macrofungal survey in the forested areas of Arunachal Pradesh, three members from Lactarius subg. Russularia i.e. L. ambiguus, L. hirtipes and L. kesiyae were collected. Detailed morphological descriptions, illustrations and nrITS-based phylogenetic estimation of these species are presented. All three species are reported for the first time from India.

Fungal Biodiversity Profiles 81-90

In this new series of Fungal Biodiversity Profiles, the authors describe seven new Russulales: five new species of Lactarius subg. Russularia and two new Russulas: descriptions and ITS sequences are provided for L. aurantiobrunneus X.H. Wang, sp. nov., L. collybioides X.H. Wang, sp. nov., L. exilis X.H. Wang, sp. nov., L. flaviaquosus X.H. Wang, sp. nov., and L. resinosus X.H. Wang, sp. nov., from China, as well as for Russula clavatohyphata R.P. Bhatt, A. Ghosh, Buyck & K. Das, sp. nov., from Indian Himalaya, and R. capillaris Buyck, sp. nov., from Madagascar. In addition, first ITS sequences are provided for several specimens of the North American R. burlinghamiae Singer. Two bamboo-inhabiting species are described from Asia: Serpula dendrocalami C.L. Zhao, sp. nov., in Boletales, is described from China, while Hymenochaete sharmae Hembrom, K. Das & A. Parihar, sp. nov., in Hymenochaetales, is described from India. Finally, in Agaricales, Laccaria indohimalayana K. Das, I. Bera & Vizzini, sp. nov., is described from Indian Himalaya.

Lactarius Subg. Lactarius (Russulaceae) in Indian Himalaya: Two New Species with Morphology and Phylogenetic Inferences

The present paper deals with two novel species in Lactarius subg. Lactarius collected from western Himalaya (India): Lactarius indozonarius sp. nov. and Lactarius thindii sp. nov. Morphological descriptions, illustrations and nrITS-based phylogenetic analyses of these species are presented.

Two novel species of Lactarius subgenus Plinthogalus from Uttarakhand Himalaya

Lactarius is a prevalent ectomycorrhizal genus in the forests of Uttarakhand Himalaya. During a macrofungal exploration in the high altitude forests of this region two interesting taxa belonging to Lactarius subg. Plinthogalus were collected. Based on detailed macro- and micromorphological observations along with nrITS-based phylogenetic analysis these taxa are proposed here as new species, Lactarius nodulisporus and Lactarius singeri.

Lactarius subgenus Russularia (Basidiomycota, Russulales): novel Asian species, worldwide phylogeny and evolutionary relationships

Lactarius subg. Russularia is a large group of milkcaps occurring almost worldwide and dominant in many ecosystems. In this study we focus on new diversity, evolutionary relationships, divergence time, and origin of the subgenus. Six conifer symbionts are described as new to science: Lactarius atrii, L. aurantionitidus, L. dombangensis, L. flavigalactus, L. lachungensis, and L. sikkimensis. Species delimitation is assessed based on the concordance between morphological characteristics and an ITS phylogeny. Infrageneric relationships were studied using a phylogeny constructed from concatenated ITS-rpb2 data using Maximum Likelihood and Bayesian inference. Results show that species in this subgenus do not cluster together according to their geographic origin. Intercontinental sister relationships between Europe/Asia/North America are common but actual conspecificity is rare. This result suggests that allopatric speciation has played an important role within this subgenus. Only few morphological characteristics tend to be phylogenetically informative, with the most important being presence or absence of true cystidia and the pileipellis structure. Two datasets were generated in order to estimate the age of L. subg. Russularia. The results suggest the origin of L. subg. Russularia to be in the Mid Miocene period.

Taxonomic relationships among non-macrocystidiate taxa of Lactarius subg. Russularia from Europe with special reference to species from Greece

Members of the ectomycorrhizal genus Lactarius form symbiotic relationships with a wide range of plant species. For the purposes of this study, 29 specimens originally assigned to L. atlanticus, L. serifluus and L. subumbonatus were examined by including all pertinent available material from Greece. The detailed study of macroscopic and microscopic characteristics by using compound optical, differential interference contrast (DIC) and scanning electron microscopy in combination with molecular approaches (ITS1-5.8S-ITS2 rDNA sequencing) permitted a clear separation between L. atlanticus and L. subumbonatus, while their basidiospore shape and height of ornamentation were found to be of diagnostic value. Moreover, the morphological delimitation between the specimens identified as L. serifluus and L. subumbonatus is not clear, and these specimens were intermixed into the same phylogenetic cluster with high support. Thus, the latter name should be considered as a synonym of the former. As concerns other related taxa of L. subg. Russularia, the American L. rubidus and L. subserifluus demonstrated relatively high evolutionary affinity with European collections of L. serifluus/L. subumbonatus and L. atlanticus, respectively.

Lactarius cucurbitoides (Russulales, Basidiomycota), a new species from South Korea supported by molecular and morphological data

A new species belonging to Lactarius subg. Plinthogalus was discovered during a long-term project on the diversity of Korean Lactarius. This species is proposed here as Lactarius cucurbitoides. The status of L. cucurbitoides as a new species is supported by molecular data and morphological features. Phylogenetic analysis based on internal transcribed spacer (ITS) sequences shows that L. cucurbitoides is closely related to L. subplinthogalus, L. friabilis, and L. oomsisiensis, with pairwise distances of 2.8–4.3%. Morphological characters of L. cucurbitoides that distinguish it from these closely related species are a pale yellow to pale orange colored pileus and non-discoloration of white latex. The new species is described and illustrated in the present paper.

Morphology and phylogeny of four new Lactarius species from Himalayan India

Four new species of Lactarius are described from Himalayan India. Lactarius olivaceoglutinus, L. pyriodorus, and L. yumthangensis belong to L. subg. Piperites and L. indochrysorrheus is closely related to some representatives of L. subg. Russularia. An ITS based phylogeny confirms the phylogenetic placement of the four new species, although the monophyly of neither Lactarius subg. Piperites nor L. subg. Russularia can be confirmed. The ITS data also suggest that the Indian species are closely related to some European and American species.

Lactarius subg. Plinthogalus: the European taxa and American varieties of L. lignyotus re-evaluated

The European species Lactarius subg. Plinthogalus were subjected to a molecular phylogenetic analysis based on ITS, LSU and rpb2 sequences. Morphological characters of the species are discussed in the light of the phylogenetic results. In addition to a broad sampling within Europe, some Asian and North American taxa also were included in the analysis. Eight European species are confirmed molecularly: L. lignyotus, L. acris, L. azonites, L. pterosporus, L. ruginosus, L. romagnesii, L. fuliginosus and L. picinus. Except the sibling species L. fuliginosus and L. picinus, all are morphologically distinct. Our results suggest that L. fuliginosus is associated exclusively with broadleaf trees and L. picinus with conifers, but this putative difference in host specificity needs to be investigated further. Lactarius subruginosus turns out to be a synonym of either L. pterosporus or L. ruginosus. The position of Lactarius terenopus remains to be clarified. The North American taxa that are closely related to the European L. lignyotus (L. fallax, L. lignyotus var. canadensis, var. nigroviolascens, var. marginatus) are not resolved. Intercontinental conspecificity was demonstrated between Europe and northern Asia but was not found between Europe and southern Asia or between Europe and North America. A taxonomic subdivision of L. subg. Plinthogalus based on the height of the spore ornamentation should be rejected.

New combinations in Lactifluus . 2. L. subg. Gerardii

In this second of a series of three papers, new combinations in the genus Lactifluus are proposed. This paper treats Lactarius subg. Gerardii (proposed here as new combination in Lactifluus). In this subgenus 17 combinations at species level are proposed.

The Australasian species of Lactarius subgenus Gerardii (Russulales)

This paper provides an overview and identification key of the Australasian species of Lactarius subg. Gerardii. A molecular phylogeny based on the nuc DNA markers ITS, LSU and rpb2, combined with detailed morphological observations resulted in the delimitation of 12 strongly supported and morphologically recognizable species. Five new agaricoid species are described here: Lactarius hora, L. coniculus, L. limbatus, L. leae and L. leonardii. Other agaricoid species belonging to subg. Gerardii are L. atrovelutinus, L. bicolor, L. ochrogalactus and L. reticulatovenosus. Lactarius venosus is also considered as a member but could not be included in the molecular analysis. Two new pleurotoid species are discovered: L. genevievae and L. conchatulus, both close relatives of L. uyedae, but each with distinct characters. Their position within subg. Gerardii is supported in the phylogeny and by their microscopic characters. This study also confirms the existence of multiple cryptic species and species complexes for which species recognition or species delimitation remains problematic as is the case for the Australian species L. wirrabara. In general, detailed macroscopic and microscopic observations are needed to identify species of L. subg. Gerardii.

Critical assessment of the Lactarius gerardii species complex ( Russulales)

This paper investigates species delimitation within the Lactarius gerardii species complex and explores its taxonomic and geographical extent. A combined molecular phylogeny based on ITS, LSU and rpb2 gene sequences is constructed and morphological characters are evaluated. While L. gerardii was originally described from North America, it has later been reported from all over Asia. Therefore a worldwide sampling range was aimed at, including species exhibiting morphological affinities with L. gerardii. The phylogenetic analyses indicate that intercontinental conspecificity in L. gerardii is absent. Thirty strongly supported clades are retrieved of which 18 are morphologically identifiable species. The group is elevated to Lactarius subg. Gerardii stat. nov. It includes, apart from L. gerardii s.l., L. atrovelutinus, L. bicolor, L. ochrogalactus, L. petersenii, L. reticulatovenosus, L. sepiaceus, L. subgerardii and L. wirrabara, as well as the pleurotoid L. uyedae. The paraphyletic nature of the genus Lactarius is confirmed. Lactarius subg. Gerardii appears not affiliated with L. subg. Plinthogalus and this can be substantiated morphologically. No representatives are known from Europe, Africa or South America. The high frequency of intercontinental sister relationships observed between America, Asia and the Australian region, suggests multiple migration and speciation events have occurred across continents.

Spore Ornamentation of North AmericanPhellodonSpecies

Analysis of spore ornamentation in the Basidiomycetes is essential for distinguishing many genera and species (i.e., Inocybe, Laccaria, Lactarius, Russula). Maire (1910) first discussed the value of spore ornamentation in taxonomic studies of the genus Russula. Mueller (1982) used size and shape of spore ornamentation in Laccaria for systematic studies of North American species. Hesler and Smith (1979) found diverse patterns of spore ornamentation within such natural groups as Lactarius subg. Plinthogalus. They stated that this feature is linked with other characters helping to define phylogenetic lines within the genus. Researchers using light microscopy to study North American stipitate hydnums found tuberculate spores in Hydnellum and Sarcodon and echinulate spores in Bankera and Phellodon (Banker, 1906; Coker and Beers, 1951; Miller