Friday, December 9, 2016

[Fungi • 2016] Amanita castanea • A New Species and Four New Records of Amanita (Amanitaceae; Basidiomycota) from Northern Thailand


Amanita castanea  
Thongbai, Tulloss, Raspé & K.D. Hyde  


Abstract
Mushrooms belonging to the genus Amanita were collected during a fungal biodiversity study in northern Thailand in 2012–2014. Morphological characteristics and molecular phylogenetic analyses were used to identify the mushrooms to species. Amanita castanea is described as new to science and compared with phenetically and phylogenetically similar species. It is assignable to Amanita stirps Citrina within Amanita series Mappae. Four other species, A. concentrica, A. rimosa, A. cf. rubromarginata and A. zangii are first reports for Thailand; detailed morphological and molecular data are provided for the Thai material.

Key words: Amanitaceae, ectomycorrhizal fungi, morphology, phylogeny



FIGURE 1. Basidiomata of Amanita castanea.
  a young and mature basidiomata. b–d basidiospores in 5% KOH. fh basidiospores in congo red. ik basidiospores in Melzer’s reagent. lo basidia and subhymenium at different stages of development. (a–o: BZ201405, holotype) (scale bar: a = 2 cm, b–k = 6 µm, l–o = 10 µm). 

Amanita castanea Thongbai, Tulloss, Raspé & K.D. Hyde, sp. nov.
Index Fungorum number: IF552009; MycoBank: MB 818356; Facesoffungi number: FoF 02074

Etymology:— castanea’ refers to the chestnut color of the pileus.
Holotype:— THAILAND, Chiang Mai Province, Doi-saket District, Thep-sadet Subdistrict, elev. 1300 m, 30 June 2014, B. Thongbai (MFLU15-1424!).

Habitat: scattered on the ground in forest of Fagaceae. 


 Four New Records
Amanita concentrica T. Oda, C. Tanaka & Tsuda, Mycoscience. 43 (1): 81, 2002a (Figure 3) 
Amanita rimosa P. Zhang & Zhu L. Yang, Fungal Diversity. 42: 124, 2010 (Figure 4)

Amanita cf. rubromarginata Har. Takah., Mycoscience. 45 (6): 372, 2004 (Figure 5)
Amanita zangii Zhu L. Yang, T.H. Li & X.L. Wu, Fungal Diversity. 6: 160, 2001 (Figure 6)  


Discussion 
In the present study, we document a novel species and four first records of Amanita species in northern Thailand. Species circumscriptions and identification are supported by both phylogenic and morphological evidence. One interesting exception might be Amanita cf. rubromarginata. The characteristics of the Thai collections, especially the colors of the pileus, agree well with the type description. However, additional collections made in southwestern Japan indicate that the colors of aging A. rubromarginata might be more different from the Thai collections than originally thought. According to illustrations in the recent book of SE Japanese fungi (Terashima et al. 2016), the center of the cap can be nearly black and the margin, olive. These colors were never observed in the Thai material. Therefore, more collections should be made from Thailand to assess the color variation.

 Further molecular studies with multiple genes that avoid loci of the nuclear ribosomal DNA cistron and expanded taxon sampling are needed to resolve the tree topology for some Amanita sections, e.g. Amanita sect. Caesareae (Sánchez-Ramírez et al. 2014, 2015), A. sect. Validae series Mappae (Drehmel et al. 1999, Hughes et al. 2013, Tulloss & Yang 2016d), A. sect. Lepidella sensu Bas (Tulloss et al. 2016) and A. sect. Phalloideae (Cai et al. 2014, Tulloss et al. 2016). A possible set of four protein-coding loci was proposed by Sánchez-Ramírez et al. (2014) and utilized in (Sánchez-Ramírez et al. 2015).


 Benjarong Thongbai, Rodham E. Tulloss, Steven L. Miller, Kevin D. Hyde, Jie Chen, Rui-Lin Zhao and Olivier Raspé. 2016. A New Species and Four New Records of Amanita (Amanitaceae; Basidiomycota) from Northern Thailand.
 Phytotaxa286(4); 211–231. DOI: 10.11646/phytotaxa.286.4.1