RESUMO
The large genus Leucoagaricus (Basidiomycota) is poorly studied in Pakistan, where the northern parts of the country are considered hot spots for biodiversity. Based on morphological and molecular data, five new species are described: Leucoagaricus badius, L. lahorensiformis, L. pakistaniensis, L. sultanii, and L. umbonatus. Descriptions and illustrations are given for the new taxa. A phylogeny based on morphology and four DNA regions, including the internal transcribed spacers (ITS1-5.8S-ITS2 = ITS) and D1-D2 domains of the 28S gene of the nuc rDNA, the gene for RNA polymerase II second largest subunit (RPB2), and the translation elongation factor 1-α gene (TEF1-α), shows that the new taxa are clustered in a clade representing Leucoagaricus section Rubrotincti subgenus Sericeomyces.
Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Agaricales/genética , Agaricales/crescimento & desenvolvimento , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Microscopia , Paquistão , Fator 1 de Elongação de Peptídeos/genética , Filogenia , RNA Polimerase II/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNARESUMO
Parasola is a genus of small, veil-less coprinoid mushrooms in the family Psathyrellaceae (Agaricales). The genus is not well documented in Asia, specifically in Pakistan. In this study we describe two new species Parasola glabra and P. pseudolactea from Pakistan, based on morphological and molecular data. Phylogeny based on three DNA regions: nuc rDNA region encompassing the internal transcribed spacers 1 and 2 along with the 5.8S rDNA (ITS), nuc 28S rDNA D1-D2 domains (28S) and translation elongation factor 1α gene (TEF1α) show that the new taxa are clustered in a clade formed by the members of section Parasola of genus Parasola. Parasola glabra with grayish pileus, slightly depressed pileal disc, lamellae separated from the stipe by pseudocollarium, basidiospores 14.5-16.5 × 9.5-11.5 × 8.0-10.5 µm, in front view broadly ovoid to oblong, some with rhomboidal outline, in side view ellipsoid, with eccentric germ-pore of 1.5 µm diameter. Parasola pseudolactea with yellowish brown to dull brown pileus, disc indistinctly umbonate, lamellae free, pseudocollarium absent, basidiospores 13.5-14.5 × 10.5-12.0 × 9.5-10.5 µm, in face view rounded triangular to heart shaped, rarely ovoid to subglobose, in side view ellipsoid to oblong, with eccentric germ-pore of 1.5 µm diam. In addition to these new species, P. auricoma and P. lilatincta were also studied. Morphological descriptions for the new species and comparison with known Parasola species are provided. Our observations highlight the diversity of Parasola in northern Pakistan and further document the need for additional systematic focus on the region's fungi.
RESUMO
The genus Agaricus is known for its medicinal and edible species but also includes toxic species that belong to section Xanthodermatei. Previous phylogenetic reconstruction for temperate species, based on sequence data of nuc rRNA gene (rDNA) internal transcribed spacers (ITS), has revealed two major groups in this section and a possible third lineage for A. pseudopratensis. Recent research in Agaricus has shown that classifications need improving with the addition of tropical taxa. In this study we add new tropical collections to section Xanthodermatei. We describe three species from collections made in Pakistan and Thailand and include them in a larger analysis using all available ITS data for section Xanthodermatei. Agaricus bisporiticus sp. nov. and A. fuscopunctatus sp. nov. are introduced based on molecular and morphological studies, whereas A. microvolvatulus is recorded for the first time in Asia. Specimens from Thailand however have a much larger pileus than the type specimens from Congo. In maximum likelihood (ML) and maximum parsimony (MP) phylogenetic analyses these three species cluster with A. pseudopratensis from the Mediterranean area and A. murinocephalus recently described from Thailand. In Agaricus section Xanthodermatei this new group is monophyletic and receives low bootstrap support whereas the two previously known groups receive strong support. Within the new group, the most closely related species share some traits, but we did not find any unifying morphological character; however the five species of the group share a unique short nucleotide sequence. Two putatively toxic species of section Xanthodermatei are now recognized in Pakistan and six in Thailand.
