First record of Chlorophyllum molybdites (G. Mey.) Massee (Basidiomycota, Agaricales, Agaricaceae) from Bucaramanga, Department of Santander, Colombia

Colombia is a megadiverse country with many macrofungi species. Despite their ecological, anthropological, and economic importance, the distribution of many macrofungal species is still scarcely known in this country. Chlorophyllum molybdites (G. Mey.) Massee is a poisonous macrofungus common in urban settings of tropical and subtropical regions. In Colombia it has only been reported in three of 32 departments. To fill this gap in knowledge we morphologically describe for the first time C. molybdites from the city of Bucaramanga, Department of Santander, extending the known distribution of this macrofungus in Colombia.


Introduction
Macrofungi include ascomycetes and basidiomycetes with large, easily observed fruiting bodies. They are an ecologically important group of organisms due to their essential roles as decomposers of organic material, in mutualistic associations with plants, and as parasites or pathogens of other fungi, plants, and animals (Pérez-Moreno et al 2020). In a developing country such as Colombia, macrofungi not only fulfill ecologically important roles but are also crucial for certain anthropological and economical activities. For example, the cultivation of edible macrofungi is an important economic activity that generates income for marginalized groups (Vargas et al. 2020) and a biotechnological alternative to obtain compounds of medical use (Suárez-Arango and Nieto 2013). Therefore, surveying and monitoring macrofungi distribution and biodiversity in this developing country is essential to support ecological, biotechnological, and ethnobiological research.
Colombia is a megadiverse country thanks to its position in the Equatorial region (Fig. 1A) and its complex geography. Although the number of studies on Colombia's biodiversity has been increasing, studies on fungal biodiversity are scarce when compared to other taxa (Arbeláez-Cortés 2013). However, a systematic study of Colombian macrofungi reported a staggering 1239 species, with more than 85% of those reported belonging to Basidiomycota (Vasco-Palacios and Franco-Molano 2013). Despite this incredible diversity, surveys on the distribution of macrofungi in Colombia are geographically biased (Franco-Molano et al. 2010). For example, Colombia is politically divided into 32 departments, and only in 24 of these have macrofungal collections been reported (Vasco-Palacios and Franco-Molano 2013). Therefore, descriptive studies that document the presence of macrofungi in neglected regions of Colombia are important to explore macrofungi distribution at the local scale. One of these neglected regions is the Department of Santander in which only 23 species of macrofungi have been reported, a small number compared to more than 300 reported in other well-studied departments (Vasco-Palacios and Franco-Molano 2013).
Chlorophyllum molybdites (G. Mey.) Massee is a poisonous macrofungus belonging to the order Agaricales, family Agaricacea (Vellinga et al. 2003). In South America, it has been reported in Argentina (Romano et al. 2013 (Pegler 1983;Guzmán 1986), Guyana (Pegler 1983;Guzmán 1986), Trinidad (Dennis 1952;Pegler 1983), and Venezuela (Dennis 1970). It has been reported as the most common cause of mushroom poisoning in Argentina (Romano et al. 2013), and in Brazil severe gastrointestinal symptoms have been reported after its consumption; these symptoms include vomiting, abdominal pain, overall weakness, and diarrhea (Remi de Meijer et al. 2007). As in North America (Blayney et al. 1980), poisoning in South America seems to be due to the misidentification of this mushroom for edible species which in South America include Macrolepiota bonaerensis (Speg.) Singer and Chlorophyllum hortense (Murrill) Vellinga (Remi de Meijer et al. 2007). Chlorophyllum molybdites has only been reported from three Colombian departments (  tropical and subtropical areas (Vellinga 2003), its correct identification is important for preventing possible poisoning in humans. In this study we morphologically describe the first specimens of C. molybdites from the urban setting of the city of Bucaramanga, the most populated city of the Department of Santander (Fig. 1B), and we extend the known distribution of this macrofungus in Colombia.

Methods
At the beginning of April 2019 several basidiocarps with typical morphological features of agaricoid mushrooms of large size were observed in the District of Mejoras Públicas, Commune 13, in the city of Bucaramanga, Department of Santander, Colombia (Fig. 1B). The basidiocarps were found in a small grassy area that separates a cycling path from a busy street. Planted Italian cypress trees (Cupressus sempervirens L.) were also found in the grassy area. Photographs of the individuals were taken on site with a digital camera, and five basidiocarps were collected on 5 April 2019, using wax paper to wrap each individual. The colors of each macroscopic feature were recorded using the CMYK color model, following the Pantone Plus Series CMYK Guide set GP5101. This color guide set is based on the concept that all colors are a combination of four basic colors: Cyan (C), Magenta (M), Yellow (Y) and Black (K). Therefore, each color is represented by four numbers separated by commas which indicate the color values of C, M, Y and K, respectively.

Discussion
In this study we observed several basidiocarps, recorded their macroscopic (Fig. 2) and microscopic (Fig. 3) morphological features, and followed the key by Ge et al. (2018). We concluded that this macrofungus belongs to the species Chlorophyllum molybdites. Although molecular methods can be used in the identification of this species (Wang et al. 2021), C. molybdites has several key morphological attributes that make it distinct from other mushroom species. The observed specimens had all these characteristics including cream-colored agaricoid basidiocarps growing in grass (Fig. 2B), brown scales on the pileus ( Fig. 2A), basidiospores with germ pore (Fig. 3C), a representative green spore print (Fig.  2F), and lamellae that turn completely greenish with age (Fig. 2D). Therefore, in this study we describe for the first time C. molybdites from the city of Bucaramanga, in the Department of Santander (Fig. 1B) and extend the known distribution of this species to a region of Colombia where macrofungal biodiversity is poorly explored (Vasco-Palacios and Franco-Molano 2013).
Chlorophyllum molybdites is commonly reported from urban settings, where it can be one of the most commonly encountered macrofungus species (Esqueda-Valle et al. 1995). We report this species in the city of Bucaramanga, the most populated municipality in the Department of Santander (DANE 2020). We found the specimens in a small patch of grass next to a busy street showing that this species can thrive in a highly disturbed area. In Medellin, Department of Antioquia (Fig. 1B), another highly populated city of Colombia and in southern Brazil, it has also been reported in similar urban areas (Somenzi Rother and Borges da Silveira 2008; Lopez-Quintero et al. 2011). As this species is poisonous and readily reported from urban settings, its rapid morphological identification is important to avoid confusing it with other edible species (Romano et al. 2013).
We observed basidiocarps between 3 April and 12 May 2019, which coincides with the first rainy season of the year in this area (IDEAM 2010). In other South American cities, this species has also been reported during the rainy season (Lopez-Quintero et al. 2011;Alves et al. 2019). We report this species from a lower elevation (1013 m above sea level) than previously known in Colombia (1450-1550 m above sea level: Vasco-Palacios and Franco-Molano 2013) and in a city with a warmer average temperature (22.6 °C: IDEAM 2010) than another city where this species has been previously reported in this country (20 °C: Lopez-Quintero et al. 2011).