Introduction

Eurotiales is a species-rich order comprising several taxonomically and economically important genera, such as Aspergillus P. Micheli ex Haller, Penicillium Link, and Talaromyces C.R. Benj. (Houbraken et al. 2020; Visagie et al. 2024). Species identification in these genera has historically been challenging due to morphological convergence and limited diagnostic characters (Peterson 2006; Visagie et al. 2024). Recently, integrative taxonomy combining morphological characters and multilocus phylogenetic analyses has improved species delimitation and classification in Penicillium and related genera, resulting in a more stable taxonomic framework (Visagie et al. 2014, 2016a; Houbraken et al. 2020).

The genus Penicillium is one of the most geographically widespread and species-rich genera of filamentous fungi and is commonly isolated from soil and other environments (Park et al. 2019; Hao et al. 2020). In recent years, more than 500 species of Penicillium have been formally described worldwide (Houbraken et al. 2020). The genus is divided into two subgenera, Aspergilloides and Penicillium, further subdivided into sections and series (Houbraken et al. 2020).

Section Lanata-Divaricata (belonging to subgenus Aspergilloides) was introduced by Thom (1930) and later reinstated based on molecular phylogenetic evidence (Houbraken and Samson 2011; Houbraken et al. 2020). This section is subdivided into five series (Dalearum, Janthinella, Oxalica, Rolfsiorum, and Simplicissima) and comprises more than 90 species (Houbraken et al. 2020; Visagie et al. 2024). Members of this section are characterised by divaricate conidiophores and colonies with broadly spreading margins, although phenotypic characters may overlap among species (Houbraken and Samson 2011; Visagie et al. 2014; Houbraken et al. 2020). Therefore, multilocus phylogenetic analyses, especially using ITS, BenA, CaM, and RPB2, or combined datasets of ITS, BenA, CaM, and RPB2, have been widely used for species delimitation and phylogenetic placement in this section (Visagie et al. 2014; Diao et al. 2019; Houbraken et al. 2020; Visagie et al. 2024).

Isolates of this section have been obtained from a broad range of substrates—including soil, pollen, and endophytic plant tissues—with soil being the dominant habitat (Houbraken and Samson 2011; Visagie et al. 2016b; Barbosa et al. 2018; Diao et al. 2019; Pangging et al. 2021; Torres-Garcia et al. 2022). Several species of Penicillium section Lanata-Divaricata have been reported from acidic, humus-rich or organic matter-rich substrates, particularly soils and decaying plant materials (Johnson 1998; Gross and Robbins 2000; Dhakar et al. 2014; Visagie et al. 2015; Diao et al. 2019). Yunnan Province is characterised by complex mountainous and plateau topography, where pronounced vertical zonation of soil types generates strong environmental heterogeneity in pH, organic matter content, and nutrient availability (Ming and Tang 2016; Xiao et al. 2021). Such heterogeneous forest ecosystems, enriched with organic matter inputs, provide diverse microhabitats that may facilitate the ecological differentiation and diversification of soilborne Penicillium lineages (Song et al. 2024).

During a survey of Penicillium diversity in agricultural soils from mountainous regions of Yunnan Province, China (including Baoshan and Pu’er cities), eight isolates were obtained and found to represent three previously undescribed species. Multi-locus phylogenetic analyses based on ITS, BenA, CaM, and RPB2, combined with detailed morphological observations, supported their placement in Penicillium section Lanata-Divaricata. These species are here described as Penicillium longyangense (series Janthinella), Penicillium longlingense (series Dalearum), and Penicillium zhenyuanense (series Rolfsiorum). This study expands the known diversity of section Lanata-Divaricata and provides new insights into the taxonomy, ecology, and geographic distribution of soilborne Penicillium species in Yunnan Province, China.