Two new toxic yellow Inocybe species from China: morphological characteristics, phylogenetic analyses and toxin detection

Abstract

Some species of Inocybes. str. caused neurotoxic poisoning after consumption around the world. However, there are a large number of species in this genus that have not been studied for their toxicity or toxin content. In this study, we report two new toxic yellow Inocybes. str. species from China based on morphological characteristics, phylogenetic analyses and toxin detection. Among the two species, Inocybe squarrosolutea is reported as a newly recorded species of China. We also describe a new species, I. squarrosofulva, which is morphologically similar to I. squarrosolutea. The new species is characterized by its ochraceous squarrose pileus, distinctly annulate cortina on the stipe, nodulose basidiospores and thick-walled pleurocystidia. Muscarine in the fruitbodies was detected by UPLC–MS/MS, the content in I. squarrosolutea and I. squarrosofulva were 136.4 ± 25.4 to 1683.0 ± 313 mg/kg dry weight and 31.2 ± 5.8 to 101.8 ± 18.9 mg/kg dry weight, respectively.

A New Muscarine-Containing Inosperma (Inocybaceae, Agaricales) Species Discovered From One Poisoning Incident Occurring in Tropical China

“…Brown et al ( 1962 ) found that the contents of muscarine differ in different collections of certain species. Li et al ( 2021b ) detected two toxic Inocybe from China, discovering that the muscarine contents in Inocybe squarrosolutea (Corner & E. Horak) Garrido and Inocybe squarrosofulva (S.N. Li, Y.G.…”

“…Among these diverse groups of poisonous mushrooms, Inocybaceae is supposed to contain a large number of muscarine-containing taxa. The species diversity of Inocybaceae was documented by a series of studies in China (Fan and Bau, 2010, 2014a,b, 2016Bau and Fan, 2018;Yu et al, 2020;Deng et al, 2021a,b;Li et al, 2021b). Inosperma genus only includes a few toxic species, but a high level of muscarine was frequently detected (Kosentka et al, 2013;Sailatha et al, 2014;Latha et al, 2020;Deng et al, 2021a;Patocka et al, 2021) and was reported constantly in mushroom poisoning incidents from tropical Asia (Chandrasekharan et al, 2020;Parnmen et al, 2021;Li et al, 2022).…”

 Pseudosperma arenarium (Inocybaceae), a new poisonous species from Eurasia, based on morphological, ecological, molecular and biochemical evidence

“…Xu et al (2020b) reported that the muscarine content of I. serotina Peck in a poisoning incident was 324.0 ± 62.4 mg/kg wet weight. Li et al (2021b) .23, 11.87 ± 3.02 and [2.08 ± 0.05 (pileus) and 6.53 ± 1.88 (stipes)] g/kg dry weight, respectively. In this study, results showed that P. arenarium is a muscarine-positive species with middle-and upper-level muscarine content and also led to three poisoning incidents with a total of seven patients in northwest China during the past 2 years (Li et al 2021a(Li et al , 2022.…”

“… serotina Peck in a poisoning incident was 324.0 ± 62.4 mg/kg wet weight. Li et al (2021b) reported that the muscarine content in I. squarrosolutea (Corner & E. Horak) Garrido and I.…”

“…Although some studies showed that the toxin amount in the cap is higher than in the stipes ( Hu et al 2012 ; Garcia et al 2015 ; Sun et al 2018 , 2019 ), the mechanism of such difference is still not clear. Li et al (2021b) reported that the muscarine content of Inocybe squarrosolutea varied a lot in different specimens. However, in this study, the muscarine content in the mushroom samples collected from the same or three different places showed no significant difference.…”