Two new species of Penicillium (Eurotiales, Aspergillaceae) and the first record of P. danzhouense from mangrove sediment in Thailand, with notes on antibacterial activity

213 Two new species of Penicillium (Eurotiales, Aspergillaceae) and the first record of P. danzhouense from mangrove sediment in Thailand, with notes on antibacterial activity Vassana Supapongsri1, Ananya Sahathippayakul1, Wanchat Sirisarn2, Mohit Chand3, Jui-Yu Chou4, Piyangkun Lueangjaroenkit1,5 1 Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand 2 Department of Microbiology, Faculty of Medicine, Kasetsart University, Bangkok, 10900, Thailand 3 International Program for Master of Science in Materials and Biological Technology, and Science Education, National Changhua University of Education, Changhua 500, Taiwan 4 Department of Biology, National Changhua University of Education, Changhua 500, Taiwan 5 Biodiversity Center Kasetsart University (BDCKU), Bangkok 10900, Thailand Corresponding author: Piyangkun Lueangjaroenkit (piy[email protected]) Copyright: © Vassana Supapongsri et al. This is an open access article distributed under terms of the Creative Commons Attribution License (Attribution 4.0 International – CC BY 4.0). Research Article Abstract Two novel species of Penicillium, comprising P. chanthaburiense sp. nov. and P. buranakarlianum sp. nov., were isolated from mangrove sediment collected at the King Rama IX International Mangrove Botanical Garden in Chanthaburi Province, Thailand. Morphological characterization combined with multilocus phylogenetic analyses of the internal transcribed spacer (ITS), β-tubulin (TUB), calmodulin (CaM), and RNA polymerase II second largest subunit (RPB2) genes placed P. chanthaburiense sp. nov. as a new member of section Exilicaulis, series Erubescentia, while P. buranakarlianum sp. nov. was assigned to section Lanata-Divaricata, series Janthinella. In addition, this study reports the first record of P. danzhouense from mangrove sediment in Thailand. Diagnostic morphological and molecular features distinguishing these taxa from their closest phylogenetic relatives are presented. These findings enrich the taxonomic framework of Penicillium and contribute to the understanding of fungal biodiversity in mangrove ecosystems. Furthermore, P. chanthaburiense sp. nov. exhibited antibacterial activity against several clinically relevant Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus (MRSA), highlighting the potential of mangrove-derived Penicillium species in antimicrobial research. Key words: Exilicaulis, Lanata-Divaricata, mangrove sediment, new species, Penicillium, phylogenetic analysis Introduction The genus Penicillium was first established by Johann Heinrich Friedrich Link in 1809 based on the characteristic brush-like conidiophores that define this morphologically distinct group. It is currently classified within the family Aspergillaceae, order Eurotiales, class Eurotiomycetes, and phylum Ascomycota (Houbraken et al. 2020). Species of Penicillium are globally Academic editor: Rajesh Jeewon Received: 27 September 2025 Accepted: 3 December 2025 Published: 22 December 2025 Citation: Supapongsri V, Sahathippayakul A, Sirisarn W, Chand M, Chou J-Y, Lueangjaroenkit P (2025) Two new species of Penicillium (Eurotiales, Aspergillaceae) and the first record of P. danzhouense from mangrove sediment in Thailand, with notes on antibacterial activity. MycoKeys 126: 213–238. https://doi. org/10.3897/mycokeys.126.172211 MycoKeys 126: 213–238 (2025) DOI: 10.3897/mycokeys.126.172211 214 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity distributed and commonly found in soil, decaying vegetation, and air, as well as in various indoor and food environments. They play essential ecological roles as decomposers and are also renowned for their industrial applications. For instance, P. chrysogenum is historically significant as the original source of the antibiotic penicillin (Gaynes 2017), while P. camemberti and P. roqueforti are indispensable in cheese ripening and flavor development (Ropars et al. 2020; Cleere et al. 2024). More recently, several Penicillium species have attracted attention as sources of novel bioactive compounds, industrial enzymes, and fermentation agents, highlighting their expanding biotechnological potential (Ifunanya et al. 2023; Shaaban et al. 2023; Lv and Zeng 2024). Recent advancements in fungal systematics, particularly the use of multilocus phylogenetic analyses combined with detailed morphological observations, have refined the taxonomy of this large genus. Houbraken et al. (2020) proposed a comprehensive revision dividing Penicillium into two subgenera, Penicillium and Aspergilloides. This subgeneric structure is relatively uncommon among filamentous fungi and reflects deep evolutionary divergence within the genus. Each subgenus encompasses multiple sections that group species based on both phylogenetic relationships and shared morphological traits. The genus is further divided into 34 sections and 102 series (Thitla et al. 2025), providing a hierarchical framework that facilitates species identification, nomenclatural stability, and the recognition of cryptic diversity. Among these, section Exilicaulis represents a taxonomically complex and morphologically variable group. The section was first formally established by Pitt (1980), with P. restrictum designated as the type species. It was originally defined to include species characterized by monoverticillate conidiophores and non-vesiculate stipes, traits that differentiated them from species with more elaborate or vesiculate structures. However, subsequent molecular studies have significantly broadened this definition. Recent multilocus phylogenetic analyses have demonstrated that species with biverticillate conidiophores, as well as those possessing solitary phialides, also belong within the phylogenetic boundaries of section Exilicaulis. As currently circumscribed, this section comprises six well-supported series: Lapidosa, Corylophila, Restricta, Citreonigra, Alutacea, and Erubescentia, reflecting the evolutionary diversity within the group (Thitla et al. 2025). Section Lanata-Divaricata of the genus Penicillium was originally proposed by Thom (1930) and later reinstated by Houbraken and Samson (2011) based on phylogenetic evidence. This section is currently subdivided into five series: Dalearum, Janthinella, Oxalica, Rolfsiorum, and Simplicissima (Visagie et al. 2024). Species within this section are predominantly isolated from soil (Visagie et al. 2015; Diao et al. 2019), although they have also been recovered from various other substrates including air (Visagie et al. 2015), house dust (Visagie et al. 2014), pollen (Barbosa et al. 2022), and leaf litter (Houbraken et al. 2011). Members of section Lanata-Divaricata are typically characterized by divaricate to biverticillate conidiophores and colonies that tend to spread broadly on culture media (Nóbrega et al. 2024). Mangrove ecosystems are recognised hotspots of fungal diversity, yet their microbial communities remain underexplored compared to terrestrial habitats. Investigating fungi from mangrove environments not only enriches our 215 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity understanding of fungal taxonomy and ecology but also holds great promise for discovering novel bioactive compounds. Such natural products may serve as valuable sources of new antibiotics, particularly against resistant bacterial pathogens, addressing urgent global health challenges. Therefore, the present study aims to isolate and identify fungi of the genus Penicillium from the King Rama IX International Mangrove Botanical Garden in Chanthaburi, Thailand. Mangrove sediments were collected and subjected to fungal isolation, leading to the discovery of two novel Penicillium species and a new record of P. danzhouense from mangrove sediments in Thailand. Based on morphological observations combined with multilocus phylogenetic analyses of ITS, TUB, CaM, and RPB2 sequences, two new species, P. chanthaburiense sp. nov. and P. buranakarlianum sp. nov., are described. Notes on their antibacterial activity are also provided, highlighting the potential of mangrove-derived Penicillium species for future antimicrobial research. Materials and methods Fungal isolation Mangrove sediments from the surface (0 cm) to a depth of 10 cm were collected from the King Rama IX International Mangrove Botanical Garden, Ban Samet Ngam, Nong Bua Subdistrict, Mueang District, Chanthaburi Province, Thailand (Fig. 1A) during the dry season (24–25 April 2023) and the rainy season (11–13 June 2023). A total of twelve sampling sites were designated using GPS coordinates (Fig. 1B–E and details shown in Table 1). The mangrove sediments were placed in sterile plastic bags, labelled with site information, and stored in an insulated box. All samples were transported to the laboratory under cool conditions (4–10 °C). Table 1. Sampling locations of the twelve sites within the study area, including associated environmental parameters (temperature, pH, and salinity) recorded during both the dry and rainy seasons. Sample sites Latitude, Longitude Temperature (°C) pH Salinity (PSU) dry rainy dry rainy dry rainy 1 12°31'43.9"N, 102°05'55.1"E 28.1 27.6 6.05 5.90 100 25 2 12°31'42.0"N, 102°05'57.6"E 29.0 27.8 5.32 5.58 85 15 3 12°31'39.9"N, 102°05'59.9"E 28.7 28.2 7.31 7.13 70 25 4 12°31'37.0"N, 102°05'57.5"E 31.7 28.4 5.69 5.87 115 30 5 12°31'40.0"N, 102°05'56.8"E 30.9 29.0 6.32 5.64 70 30 6 12°31'42.7"N, 102°05'54.1"E 30.5 28.3 5.57 5.44 80 35 7 12°31'40.8"N, 102°05'52.5"E 30.7 28.4 5.89 5.70 50 35 8 12°31'38.9"N, 102°05'55.5"E 33.0 28.5 5.54 5.40 105 40 9 12°31'35.6"N, 102°05'56.8"E 33.1 29.6 6.53 5.93 45 30 10 12°31'33.6"N, 102°05'55.6"E 33.7 31.1 4.89 5.83 40 15 11 12°31'37.4"N, 102°05'50.3"E 35.9 30.8 6.22 5.88 50 25 12 12°31'39.5"N, 102°05'49.1"E 35.0 32.9 6.00 5.19 60 35 216 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Mangrove sediment samples were air-dried under shade and subjected to serial dilution plating, with dilution levels ranging from 1:100 to 1:1,000 in sterile distilled water. From each dilution, 100 µL aliquots were spread onto Potato Dextrose Agar (PDA) and Martin’s Rose Bengal Agar (MRBA). Both media were supplemented with streptomycin (100 µg/mL) to inhibit bacterial growth. The salinity and pH of the media were adjusted using sodium chloride (NaCl) to match the measured values of the corresponding sediment samples. Plates were incubated at room temperature (28–32 °C) for 3–5 days. Fungal colonies with distinct morphological characteristics were selected and purified using the hyphal tip isolation technique on PDA. The pure cultures were deposited and permanently preserved in a metabolically inactive state in two culture collection at the Thailand Bioresource Research Centre (TBRC) in Thailand and the NITE Biological Resource Centre (NBRC) in Japan. Morphological characterisation Colony morphology, growth rate, sporulation, and pigment production were recorded after 7 days of incubation at 25 °C in darkness on various media, including malt extract agar (MEA), Czapek yeast extract agar with 20% sucrose (CY20S), Czapek yeast extract agar with 5% NaCl (CYAS), Czapek’s agar (CZ), oatmeal agar (OA), and creatine sucrose agar (CREA). In addition, growth on Czapek yeast extract agar (CYA) was also performed at 25 °C, 30 °C, and 37 °C in darkness for 7 days to determine the macroscopic colony characteristics. Colony colours (both obverse and reverse) were assessed using the Methuen handbook of colour (Kornerup and Wanscher 1967). The microscopic features of the fungal isolates were assessed using a compound light microscope (Nikon Instech Co., Ltd., Tokyo, Japan). Specimens were stained with lactophenol cotton blue and observed for structural details. The characteristics of conidiophores, stipes, conidiogenous cells, conidia, and other relevant structures were examined. Digital images and morphometric data were captured and analysed using the NIS-Elements D imaging software (Nikon Instech Co., Ltd., Tokyo, Japan). To examine surface ultrastructure, scanning electron microscopy (SEM) was performed following the protocol outlined by Haranto et al. (2024). Fungi were cultured on potato dextrose agar (PDA) plates for 7–14 days, after which fungal colonies were cut into 1 × 1 cm sections. The samples were fixed overnight at 4 °C in 2% (v/v) glutaraldehyde prepared in 100 mM phosphate buffer (pH 7.2). After fixation, the samples were rinsed three times with the same buffer and then dehydrated through a graded ethanol series (10% to 100%) at one-hour intervals. The dehydrated specimens were subjected to critical point drying, sputter-coated with gold, and examined using a Quanta 450 scanning electron microscope (FEI, USA). DNA sequencing and phylogenetic analysis Fungal isolates were grown on PDA at room temperature (25 ± 2 °C) for 3–5 days. Fresh mycelia (~50 mg) were harvested and transferred into 1.5 mL microcentrifuge tubes containing 700 µL of extraction buffer composed of 100 mM TrisHCl (pH 8.0), 20 mM EDTA (pH 8.0), 1.4 M NaCl, 2% (w/v) cetyltrimethylammonium bromide (CTAB), and 4% (w/v) polyvinylpyrrolidone (PVP). The samples 217 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Figure 1. The King Rama IX International Mangrove Botanical Garden, Chanthaburi Province, Thailand. A. Map showing all 12 sampling sites; B–E. Representative sampling sites where the novel Penicillium species were frequently isolated; B. Sediment at sampling site 6; C. sampling site 7; D. sampling site 9; E. sampling site 12. Remarkably, both newly described Penicillium species were consistently recovered from sample sites 6 and 7. Photograph 1A courtesy of the Department of Marine and Coastal Resources (DMCR). 218 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity were homogenised using sterile micropestles and incubated at 65 °C for 30 minutes in a water bath. Following incubation, 700 µL of chloroform:isoamyl alcohol (24:1) was added and mixed thoroughly. The mixture was centrifuged at 12,000 rpm for 10 minutes, and the aqueous phase was transferred to a new tube. An equal volume of cold isopropanol was added to precipitate the DNA, followed by centrifugation at 12,000 rpm for 2 minutes. The resulting DNA pellet was washed with 300 µL of cold 70% ethanol, centrifuged again at 12,000 rpm for 2 minutes, and air-dried. The purified DNA was resuspended in 30 µL of deionised water and stored at −20 °C until use. Genomic DNA extracted from fungal isolates was used as a template to amplify four genetic loci: the ITS region, TUB, CaM, RPB2. PCR amplification was performed using the following primer pairs: ITS1/ITS4 for ITS (White et al. 1990), Bt2a/Bt2b for TUB (Glass and Donaldson 1995), CMD5/CMD7 for CaM (Hong et al. 2006), and 5F/7CR for RPB2 (Liu et al. 1999). The annealing temperatures for ITS, TUB, CaM, and RPB2 were 52 °C, 52 °C, 58 °C, and 56 °C, respectively. Each PCR reaction was carried out in a final volume of 50 μL, containing 1× PCRBIO Taq Mix Red (PCR Biosystems, UK) and 0.5 μM of each primer. Thermal cycling conditions followed the protocol described by Leetanasaksakul et al. (2024). PCR products were visualised on 1.5% agarose gels and subsequently purified using the MEGAquick-spin™ Plus Total Fragment DNA Purification Kit (iNtRON Biotechnology, Korea). Bidirectional sequencing was conducted by Bionics Inc. (Seoul, South Korea). Forward and reverse reads were assembled using MEGA version 11 (Tamura et al. 2021). The resulting consensus sequences were compared to existing sequences in the GenBank database using the BLASTn algorithm (Altschul et al. 1997) to determine similarity with known fungal taxa. For phylogenetic analyses, ITS, TUB, CaM, and RPB2 sequences of type strains and representative species of Penicillium (subgenus Aspergilloides) from sections Exilicaulis and Lanata-Divaricata were retrieved from GenBank (Suppl. material 1). Phylogenetic trees were reconstructed separately for each section based on concatenated alignments of the four loci (ITS, TUB, CaM, and RPB2) using the maximum likelihood (ML) method General Time Reversible (GTR) model implemented in MEGA11 (Tamura et al. 2021). Clade support was assessed by bootstrap analysis with 1,000 replicates (Felsenstein 1985). P. anatolicum (section Citrina) and P. glabrum (section Aspergilloides) were used as outgroup taxa for the trees of sections Exilicaulis and Lanata-Divaricata, respectively. Crude extract preparation The three Penicillium species were each cultivated in 100 mL of Potato Dextrose Broth (PDB) in six individual Erlenmeyer flasks and incubated for one month at room temperature under shaking conditions at 200 rpm. Each flask was inoculated with approximately 105 spores/mL of the respective fungal isolate. Following incubation, the cultures were filtered through Whatman No.1 filter paper to separate the mycelial biomass from the culture supernatant. The supernatant was extracted three times with an equal volume of ethyl acetate (1:1, v/v per extraction) (Díaz-González et al. 2025). The pooled ethyl acetate fractions were concentrated to dryness using a rotary evaporator at 40 °C. 219 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity The remaining aqueous phase was freeze-dried to obtain the water-soluble fraction. Both ethyl acetate and aqueous extracts were stored and subsequently used for antibacterial activity assays. Antibacterial activity assay by agar well diffusion The antibacterial activity of the fungal extracts was evaluated using the agar well diffusion method (Mousa et al. 2024). The crude extracts obtained from the ethyl acetate fraction were dissolved in 20% dimethyl sulfoxide (DMSO), while the aqueous extracts were dissolved in sterile distilled water. Both types of extracts were prepared at a final concentration of 10 mg/mL. A total of 13 bacterial strains, including standard strains and clinical isolates, were used for the assay: Staphylococcus aureus ATCC 25923, S. aureus ATCC 29213, methicillin-resistant S. aureus (clinical isolate), Bacillus subtilis ATCC 6051, B. subtilis 7988 (clinical isolate), Bacillus cereus ATCC 11778, Escherichia coli ATCC 25922, E. coli O157:H7 (clinical isolate), Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063, Shigella enterotidis (clinical isolate), Salmonella enterica serotype Typhi (clinical isolate), and Vibrio cholerae (clinical isolate). Each bacterial suspension was adjusted to a turbidity equivalent to 0.5 McFarland standard (1.5 × 108 CFU/mL) and uniformly spread onto the surface of Mueller-Hinton agar plates using a sterile cotton swab. Wells with diameter of 6 mm were aseptically punched into the agar, and 100 µL of each extract solution was carefully loaded into the wells. Streptomycin at a concentration of 10 mg/mL was used as a positive control, while 20% DMSO served as a negative control. The plates were then incubated at 37 °C for 18 to 24 hours. The antibacterial activity was assessed by measuring the diameter of the clear inhibition zones around each well in millimetres. All experiments were conducted in triplicate to ensure reproducibility. Results A total of 160 fungal isolates were recovered from mangrove sediments at the King Rama IX International Mangrove Botanical Garden, Chanthaburi, Thailand. Among these, Penicillium was the dominant genus, comprising 68 isolates (42.5%). Sixteen isolates were preliminarily identified as Penicillium based on morphology and were of particular interest because they displayed distinct morphological traits that differed from known species in the genus. Sequences of ITS, TUB, CaM, and RPB2, combined with multilocus phylogenetic analyses, provided a framework to assess their taxonomy and supported the recognition of new species within sections Exilicaulis and Lanata-Divaricata. Novel species delineation and identification Multilocus sequence comparisons revealed distinct patterns among the 16 isolates. Six fungal isolates—two from the rainy season (DMKU-RS6P10, DMKU-RS7P10) and four from the dry season (DMKU-SS6P3T, DMKU-SS7M1, DMKU-SS9P12, DMKU-SS11P5)—showed ITS sequences that were identical or differed by only two nucleotides. TUB and RPB2 sequences were identical or varied by a single nucleotide, while CaM sequences were completely identical. 220 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Compared with P. dimorphosporum NRRL 52071, ITS and TUB sequences shared 97.9% similarity (11 and 9 nucleotide differences, respectively), CaM sequences showed 96.0% similarity (28 differences), and RPB2 sequences were 99.0% similar (9 differences). Phylogenetic analysis was conducted on 73 Penicillium taxa from section Exilicaulis, including the six isolates using a combined dataset of ITS, TUB, CaM, and RPB2 sequences. Maximum likelihood analysis placed the six new isolates in a distinct phylogenetic position, separate from other recognised species, with strong bootstrap support (100%). These strains formed a sister clade with P. dimorphosporum NRRL 52071 and belonged to the series Erubescentia. (Fig. 2), supporting their recognition as a novel species. Another six fungal isolates collected during the dry season (DMKU-SS6M3, DMKU-SS7M2, DMKU-SS7P3, DMKU-SS9M4, DMKU-SS11P3, and DMKU-SS12P2) showed identical sequences across all four loci (ITS, TUB, CaM, and RPB2). BLASTn searches indicated 100% similarity of ITS and TUB with Penicillium danzhouense CGMCC 3.25204, while CaM showed 99.8% similarity (1 nucleotide difference). Phylogenetic analysis of section Exilicaulis using a concatenated ITS, TUB, CaM, and RPB2 dataset confirmed that all six isolates belong to P. danzhouense within the Series Erubescentia clade, representing the first report of this species from mangrove sediments in Thailand. Notably, while P. danzhouense was previously reported based on a single isolate from tidal flat sediments in China, the recovery of six independent isolates in the present study provides strong evidence for its establishment and adaptation in mangrove sediment ecosystems. Finally, four isolates—three fungal isolates collected during the rainy season (DMKU-RS5M3T, DMKU-RS6P1, and DMKU-RS12P5) and one from the dry season (DMKU-SS7P5). Phylogenies of series Janthinella within section Lanata-Divaricata were reconstructed from individual datasets of the ITS, TUB, CaM, and RPB2 genes (Suppl. material 2), as well as from a concatenated dataset of these genes comprising 112 representative taxa across five recognized series (Janthinella, Rolfsiorum, Dalearum, Simplicissima, and Oxalica), with P. glabrum (section Aspergilloides, series Glabra) as the outgroup. In both the single-gene and combined analyses, the four isolates formed a strongly supported clade closely related to, but distinct from, P. ehrlichii, P. melanosporum, P. meloforme, and P. siccitolerans (Fig. 3). The combined phylogeny further indicated that these strains belong to series Janthinella (section Lanata-Divaricata) and supports their recognition as a novel species. Taxonomy Penicillium chanthaburiense Supapongsri, Sahathippayakul & Lueangjaroenkit, sp. nov. MycoBank No: 859666 Remark. In: subgenus Aspergilloides, section Exilicaulis series Erubescentia. Etymology. The specific epithet “chanthaburiense” refers to the type locality, which is in Chanthaburi Province in Thailand. Holotype. Thailand • Chanthaburi Province, Mueang District, Nong Bua Subdistrict, Ban Samet Ngam, King Rama IX International Mangrove Botanical Garden; isolated from mangrove sediment during the dry season, 24 April 2023, 221 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Figure 2. Maximum likelihood (ML) phylogenetic tree of Penicillium species in section Exilicaulis, based on a concatenated dataset of ITS, TUB, CaM, and RPB2 sequences. The tree illustrates the phylogenetic positions of the newly described species relative to closely related taxa. Bootstrap support values ≥ 70% are indicated at the nodes. Strain numbers follow species names, with GenBank accession numbers for ITS, TUB, CaM, and RPB2 provided in parentheses. Penicillium anatolicum CBS 479.66 was used as the outgroup. Scale bar: patristic distance of 0.050. 228 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity undulate margins; mycelium white (1A1), velvety; sporulation very sparse, conidia en masse not determined; sclerotia and exudate absent; no soluble pigments produced; reverse pale yellow (4A3) (Fig. 6I). On CYA at 37 °C after 7 days, colonies were umbonate with undulate margins; mycelium white (1A1), velvety; sporulation absent to very sparse, conidia en masse not determined; sclerotia and exudate absent; no soluble pigments produced; reverse champagne (4A4) (Fig. 6J). Micromorphology. Conidiophores monoverticillate, unbranched, smooth-walled, hyaline, measuring 7.0–24.0 × 1.0–2.0 µm (Fig. 7A, B). Phialides ampulliform, occurring singly or in groups of up to seven per conidiophore, smooth-walled, hyaline, measuring 5.0–10.5 × 1.5–3.0 µm (Fig. 7C). Conidia globose measuring 2.0–3.0 µm. Under scanning electron microscopy (SEM), conidia appear globose and distinctly rugose (Fig. 7D). Sclerotia not observed. Sexual morph absent. Figure 7. Morphological features of Penicillium danzhouense DMKU-SS7M2. A, B. Conidiophores are monoverticillate, unbranched, smooth-walled, and hyaline; C. Phialides are ampulliform, occurring singly or in groups of up to seven per conidiophore, smooth-walled, and hyaline; D. Conidia are globose with distinctly rugose surfaces as shown by SEM. Scale bars: 20 µm (A); 15 µm (B); 5 µm (C); 2 µm (D). 229 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Habitat and distribution. Tidal flat sediment in Hainan Province, China in 2020 and Mangrove sediment in Chanthaburi Province, Thailand in 2023. Note. Penicillium danzhouense was isolated from Thailand and represents the first record of this species in the country, and only the second report worldwide. Phylogenetic analysis based on a multilocus dataset placed our isolates within the same clade as P. danzhouense CGMCC 3.25204, the ex-type strain (Fig. 2), with strong statistical support. The morphological characteristics of our isolates closely correspond to the description of P. danzhouense by Liu et al. (2023), particularly in conidial size (2–3 μm), colony colours on CYA, MEA and PDA (white), reverse colony colours (light yellow), and colony diameter on PDA, all of which fall within the known range of the species. The environmental conditions of the sampling sites were also comparable, as the species was previously reported from tidal flat sediment in China and is here isolated from mangrove sediment in Thailand. However, minor morphological deviations were observed when compared with the holotype. The conidiophores of our isolates tend to be shorter (7– 24 μm vs. 12–40 μm in the holotype), whereas the phialides are slightly larger (5–10.5 μm vs. 4.6–8.7 μm). The number of phialides per conidiophore also varied slightly (1–7 in our isolates vs. 2–5 in the holotype). Growth characteristics on different media additionally showed subtle differences: colonies on CYA grew more slowly than the holotype (18–19 mm vs. 21–24 mm), whereas growth on MEA (20–23 mm vs. 14–17 mm) and on CYA at 37 °C (10–12 mm vs. 6–7 mm) was comparatively faster. Overall, the congruence of phylogenetic evidence and morphological similarity, with only minor intraspecific variations, supports the identification of these isolates as Penicillium danzhouense. Penicillium buranakarlianum Supapongsri, Sahathippayakul & Lueangjaroenkit, sp. nov. MycoBank No: 859669 Remark. In: subgenus Aspergilloides, section Lanata-Divaricata series Buranakarliana. Etymology. The specific epithet “buranakarlianum” is named in honour of Associate Professor Dr. Lerluck (Buranakarl) Chitadon, a senior faculty member of the Department of Microbiology, Faculty of Science, Kasetsart University. She served as the academic advisor for Assistant Professor Dr. Piyangkun Lueangjaroenkit from his undergraduate through to doctoral studies. Her guidance, knowledge, and unwavering support profoundly shaped his academic journey and she continues to encourage and inspire the authors. Holotype. Thailand • Chanthaburi Province, Mueang District, Nong Bua Sub-district, Ban Samet Ngam, King Rama IX International Mangrove Botanical Garden; isolated from mangrove sediment during the rainy season, 11 June 2023, V. Supapongsri, A. Sahathippayakul & P. Lueangjaroenkit; holotype, TBRC 18803, isotype NBRC 116999, ex-type living culture, DMKU-RS5M3, metabolically inactive culture preserved state, TBRC 18803 and NBRC 116999. GenBank accession numbers. ITS: LC796823; TUB: LC871416; CaM: LC871417; RPB2: LC871418. Colony diam. (in mm) 7 days, 25 °C: CYA 40-46, MEA 48-54, CY20S 41-46, CYAS 16-18, CZ 23-26, OA 43-47, CREA 33-35 and PDA 40-50. 7 days, 30 °C: CYA 40-46. 7 days, 37 °C: CYA no growth. 230 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Culture characteristics. On CYA at 25 °C after 7 days, colonies were slightly umbonate with undulate margins; mycelium yellowish white (4A2) at the centre and white (1A1) toward the margins, velvety in texture; sporulation very sparse, conidia en masse not determined; sclerotia absent; exudate absent; no soluble pigments produced; reverse pale yellow (4A3) (Fig. 8A). On MEA at 25 °C after 7 days, colonies were slightly umbonate with undulate margins; mycelium white (1A1), velvety in texture; sporulation very sparse, conidia en masse not determined; sclerotia abundant, white (1A1); exudate hyaline; no soluble pigments produced; reverse champagne (4A4) (Fig. 8B). On CY20S at 25 °C after 7 days, colonies were slightly raised with undulate margins; mycelium white (1A1), velvety in texture; sporulation very sparse, conidia en masse not determined; sclerotia and exudate absent; no soluble pigments produced; reverse pale yellow (4A3) (Fig. 8C). On CYAS at 25 °C after 7 days, colonies were slightly raised with filiform margins; mycelium white (1A1), velvety in texture; sporulation very sparse, conidia en masse not determined; sclerotia and exudate absent; no soluble pigments produced; reverse pale yellow (4A3) (Fig. 8D). On CZ at 25 °C after 7 days, colonies were umbonate with undulate margins; mycelium white (1A1), velvety in texture; sporulation very sparse, conidia en masse not determined; sclerotia and exudate absent; no soluble pigments produced; reverse yellowish white (4A2) (Fig. 8E). On OA at 25 °C after 7 days, colonies were plain with entire margins; mycelium white (1A1), granular in texture; sporulation absent to very sparse; sclerotia abundant, white (1A1); exudate absent; no soluble Figure 8. Penicillium buranakarlianum DMKU-RS5M3T. A–H. Colonies grown for 7 days at 25 °C on CYA, MEA, CY20S, CYAS, CZ, OA, CREA, and PDA, respectively; I. Colonies grown for 7 days on CYA at 30 °C; J. No growth on CYA at 37 °C. 231 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity pigments produced; reverse white (1A1) (Fig. 8F). On CREA at 25 °C after 7 days, colonies showed poor growth; no acid production observed (Fig. 8G). On PDA at 25 °C after 7 days, colonies were slightly umbonate with undulate margins; mycelium white (1A1), granular in texture; sporulation very sparse, conidia en masse not determined; sclerotia abundant, white (1A1); exudate absent; no soluble pigments produced; reverse pale yellow (3A3) at the centre, white (1A1) at the margins (Fig. 8H). On CYA at 30 °C after 7 days, colonies were slightly umbonate with undulate margins; mycelium white (1A1), velvety in texture; sporulation very sparse, conidia en masse not determined; sclerotia and exudate absent; no soluble pigments produced; reverse pale yellow (4A3) (Fig. 8I). On CYA at 37 °C after 7 days, no growth were observed (Fig. 8J). Asexual spores were rarely observed, while abundant sclerotia were produced on PDA and MEA (Fig. 9D, E). Micromorphology. Conidia and Conidiophores were rarely produced (Fig. 9A–C). Abundant Sclerotia were produced (Fig. 9D, E). Conidiophores were monoverticillate to diverticillate, hyaline, smooth-walled, measuring 8.0–93.5 × 2.5–5.0 µm. Phialides ampulliform, borne singly or in groups of up to four per conidiophore, smooth-walled, hyaline, measuring 8.0–19.0 × 3.0–5.0 µm. Conidia were subglobose to ovoid, measuring 3.0–6.0 × 2.5–5.0 µm. Under scanning electron microscopy, conidia appear with delicate surface ornamentation consisting of very short ridges (Fig. 9F). Sexual morph was not observed. Habitat and distribution. Mangrove sediment; only known from Chanthaburi Province, Thailand. Figure 9. Morphological features of Penicillium buranakarlianum DMKU-RS5M3T. A–C. Conidia and conidiophores were rarely observed. Conidiophores are monoverticillate to diverticillate, hyaline, and smooth-walled. Phialides are ampulliform, borne singly or in groups of up to four per conidiophore, smooth-walled, and hyaline; D, E. Abundant sclerotia were produced; F. Under scanning electron microscopy, conidia appear subglobose to ovoid with delicate surface ornamentation consisting of very short ridges. Sexual morph was not observed. Scale bars: 15 µm (A–D); 10 µm (E); 2 µm (F). 232 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Notes. Penicillium buranakarlianum is classified in section Lanata-Divaricata, series Janthinella. Phylogenetic analyses resolved it in a clade with P. ehrlichii (Stolk and Scott 1967), P. melanosporum, P. siccitolerans (Rodriguez-Andrade et al. 2021) and P. meloforme (Udagawa and Horie 1973). However, sexual morphs (cleistothecia) are absent in P. buranakarlianum but present in P. ehrlichii and P. meloforme. Moreover P. melanosporum further differs by producing conidia that are olive-green to dark brown and enveloped by a dark brown sheath at maturity. Although both P. buranakarlianum and P. siccitolerans produce abundant sclerotia, the latter can grow at temperatures of up to 40 °C, whereas P. buranakarlianum is unable to grow at 37 °C. Antibacterial activity against pathogenic bacteria The antibacterial activity of the Penicillium species is presented in Table 2. The ethyl acetate fraction of the crude extract from P. chanthaburiense DMKU-SS6M3T exhibited inhibitory activity against Gram-positive bacteria, particularly S. aureus, B. subtilis, and B. cereus (Fig. 10). Notably, it also showed activity against MRSA. However, this extract showed no activity against any of the tested Gram-negative bacteria. Furthermore, the aqueous phase obtained after the ethyl acetate extraction of P. chanthaburiense DMKU-SS6M3T did not exhibit any antibacterial activity (Fig. 10). In addition, the ethyl acetate and aqueous fractions from P. danzhouense DMKU-SS7M2 and P. buranakarlianum DMKU-RS5M3T showed no antibacterial activity against any of the tested bacterial strains. Discussion The genus Penicillium is one of the most morphologically diverse and ecologically widespread fungal genera, encompassing taxa that thrive across a variety of terrestrial and aquatic ecosystems (Houbraken et al. 2020). Mangrove ecosystems, characterised by high salinity, tidal fluctuation, and organic-rich substrates, have emerged as promising but underexplored habitats for discovering novel fungal Table 2. Antibacterial activity of ethyl acetate extract from three Penicillium species isolated from mangrove sediment in Thailand. Bacterial strains Size of inhibition zone (mm.) P. chanthaburiense DMKU-SS6M3T P. danzhouense DMKU-SS7M2 P. buranakarlianum DMKU-RS5M3T Methicillin resistance Staphylococcus aureus (Clinical isolate) 12.79 ± 0.57 0.00 ± 0.00 0.00 ± 0.00 Staphylococcus aureus ATCC 25923 14.70 ± 0.33 0.00 ± 0.00 0.00 ± 0.00 Staphylococcus aureus ATCC 29213 12.50 ± 0.19 0.00 ± 0.00 0.00 ± 0.00 Bacillus subtilis ATCC 6051 16.50 ± 0.30 0.00 ± 0.00 0.00 ± 0.00 Bacillus subtilis 7988 (Clinical isolate) 14.42 ± 0.56 0.00 ± 0.00 0.00 ± 0.00 Bacillus cereus ATCC 11778 16.12 ± 0.07 0.00 ± 0.00 0.00 ± 0.00 Escherichia coli ATCC 25922 0.00 ± 0.00 0.00 ± 0.00 0.00 ± 0.00 Escherichia coli O157:H7 (Clinical isolate) 0.00 ± 0.00 0.00 ± 0.00 0.00 ± 0.00 Psudomonas aeruginosa ATCC 27853 0.00 ± 0.00 0.00 ± 0.00 0.00 ± 0.00 Klebsiella pneuminiae ATCC 70063 0.00 ± 0.00 0.00 ± 0.00 0.00 ± 0.00 Shigella enterotidis (Clinical isolate) 0.00 ± 0.00 0.00 ± 0.00 0.00 ± 0.00 Salmonella enterica serotype Typhi (Clinical isolate) 0.00 ± 0.00 0.00 ± 0.00 0.00 ± 0.00 Vibrio cholerae (Clinical isolate) 0.00 ± 0.00 0.00 ± 0.00 0.00 ± 0.00 233 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity diversity (Norphanphoun et al. 2019; Apurillo et al. 2025,). This study introduces two new species of Penicillium (P. chanthaburiense, and P. buranakarlianum) and first record P. danzhouense recovered from mangrove sediment samples collected at the King Rama IX International Mangrove Botanical Garden in eastern Thailand. These findings underscore the high and yet underestimated diversity of Penicillium species inhabiting mangrove ecosystems. Previous studies have suggested that saline, organic-rich environments such as mangroves may serve as specialised niches driving fungal diversification (Jones et al. 2011; Lee et al. 2019). The consistent recovery of two new taxa from multiple sampling sites, particularly sample sites 6 and 7, further suggests that these species are not atypical or sporadic occurrences but may play active ecological roles in the microbial community in mangrove sediment. Previously, only two species in section Exilicaulis (P. laeve and P. terrae) had been reported from Thailand, both isolated from forest soil (Ando et al. 1998; Thitla et al. 2025). The identification of P. chanthaburiense from mangrove sediment not only expands the known habitat range of this section but also represents the third species of Exilicaulis recorded in the country. Similarly, the description of P. buranakarlianum in section Lanata-Divaricata adds a third species to this section in Thailand, following P. singorense from house dust (Visagie et al. 2014) and P. chaingmaiense from a forest dump site (Thitla et al. 2025). Figure 10. Antibacterial activity of Penicillium chanthaburiense DMKU-SS6M3T. A. Methicillin resistance Staphylococcus aureus (Clinical isolate); B. Staphylococcus aureus ATCC 25923; C. Staphylococcus aureus ATCC 29213; D. Bacillus subtilis ATCC 6051; E. Bacillus cereus ATCC 11778; F. Escherichia coli ATCC 25922. “ea” indicates the crude extract from the ethyl acetate phase; “aq” indicates the crude extract from the aqueous phase; “+” denotes the positive control (streptomycin, 10 mg/mL); “−” denotes the negative control (20% DMSO). 234 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity In conclusion, the description of P. chanthaburiense and P. buranakarlianum adds to the growing inventory of mangrove-associated fungi and highlights the ecological breadth of Penicillium in saline habitats. Further exploration of these ecosystems will undoubtedly continue to yield novel fungal lineages and refine our understanding of the evolution and taxonomy of Penicillium. Among these three Penicillium species, only P. chanthaburiense DMKU-SS6MT showed notable antibacterial activity, specifically against several Gram-positive bacteria, including S. aureus, B. subtilis and B. cereus, when extracted with ethyl acetate. In contrast, aqueous extracts of P. chanthaburiense and all extracts of P. danzhouense and P. buranakarlianum showed no activity. These findings highlight not only the strain-specific nature of antibacterial activity but also the importance of the extraction method. Ethyl acetate is a semi-polar organic solvent capable of extracting a wide range of non-polar to moderately polar secondary metabolites, including many bioactive compounds such as polyketides and alkaloids. In contrast, aqueous extractions are more likely to capture polar compounds, which may lack antibacterial properties or may not effectively penetrate bacterial membranes. The observed selectivity toward Gram-positive bacteria further supports this, as their cell walls consist of a thick peptidoglycan layer without an outer membrane, making them more accessible to many hydrophobic or amphipathic compounds. On the other hand, Gram-negative bacteria possess an outer membrane rich in lipopolysaccharides that can restrict the entry of such compounds, potentially explaining the lack of activity. Collectively, these results underscore the potential of P. chanthaburiense as a promising source of bioactive metabolites, particularly against Gram-positive pathogens, and emphasize the critical role of the extraction strategy in bioactivity-guided screening. The ability of P. chanthaburiense to inhibit MRSA is of particular interest given the global concern over antimicrobial resistance. Mangrove-derived fungi have been increasingly recognised as a valuable source of novel bioactive compounds due to their adaptation to stressful, nutrient-variable environments (Xu et al. 2015). The findings in this study suggest that P. chanthaburiense may contribute to this potential and underscore the utility of exploring underexplored habitats such as mangrove sediments in the search for new antimicrobial agents. Future studies should aim to isolate and chemically characterise the specific secondary metabolites responsible for the observed antibacterial activity. Identifying and elucidating the structure of these compounds could provide valuable information for the development of new antibiotics, particularly against resistant bacterial strains. The discovery of bioactivity in P. chanthaburiense thus opens an exciting avenue for future research at the interface of fungal taxonomy, natural product chemistry, and drug discovery. Additional information Conflict of interest The authors have declared that no competing interests exist. Ethical statement No ethical statement was reported. 235 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Use of AI No use of AI was reported. Funding This research was supported financially by the National Research Council of Thailand (NRCT) under Grant No. N25A660324. This research is funded by Faculty of Science, Kasetsart University through the Graduate Fellowship Programme, which provided funding to Ms. Vassana Supapongsri for her Master’s degree research. The authors also gratefully acknowledge the SciKU Summer Internships 2025 programme, Faculty of Science, Kasetsart University, and Kasetsart University International College for supporting Mr. Mohit Chand, a Master’s student in the International Programme in Materials and Biotechnology, National Changhua University of Education (NCUE), Taiwan, to conduct experiments in Thailand during his three-month research internship. Author contributions Vassana Supapongsri: Funding, Data analysis, Writing and Editing; Ananya Sahathippayakul: Data analysis; Wanchat Sirisarn: Data analysis; Mohit Chand: Data analysis; Jui-Yu Chou: Writing Review and Editing; Piyangkun Lueangjaroenkit: Funding, Principal investigation, Supervision, Data analysis, Writing Review and Editing. Author ORCIDs Wanchat Sirisarn https://orcid.org/0000-0002-9290-0238 Jui-Yu Chou https://orcid.org/0000-0002-4770-3702 Piyangkun Lueangjaroenkit https://orcid.org/0000-0002-1362-2971 Data availability All of the data that support the findings of this study are available in the main text or Supplementary Information. References Altschul SF, Madden TL, Schäffer AA, Zhang J, Zhang Z, Zhang Z, Miller W, Lipman DJ (1997) Gapped BLAST and PSI-BLAST: A new generation of protein database search programs. Nucleic Acids Research 25(17): 3389–3402. https://doi.org/10.1093/nar/25.17.3389 Ando K, Nawawi A, Manoch L, Pitt JI (1998) Three new species and a new combination in the genus Torulomyces from soil. Mycoscience 39(3): 313–318. https://doi. org/10.1007/BF02464014 Apurillo CCS, Phukhamsakda C, Hyde KD, Thiyagaraja V, Jones EBG (2025) New fungal genus, three novel species and one new record from mangroves, with reclassification of Melanconiella (Melanconiellaceae) species. MycoKeys 116: 25–52. https://doi. org/10.3897/mycokeys.116.137351 Barbosa RDN, Santos JEF, Bezerra JDP, Istel Ł, Houbraken J, Oliveira NT, Souza-Motta CM (2022) Brazilian Atlantic Forest and Pampa Biomes in the spotlight: an overview of Aspergillus, Penicillium, and Talaromyces (Eurotiales) species and the description of Penicillium nordestinense sp. nov. Acta Botanica Brasilica 36: e2021abb0390. https://doi.org/10.1590/0102-33062021abb0390 Cleere MM, Novodvorska M, Geib E, Whittaker J, Dalton H, Salih N, Hewitt S, Kokolski M, Brock M, Dyer PS (2024) New colours for old in the blue-cheese fungus Penicillium roqueforti. Npj Science of Food 8: 3. https://doi.org/10.1038/s41538-023-00244-9 236 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity Diao YZ, Chen Q, Jiang XZ, Houbraken J, Barbosa RN, Cai L, Wu WP (2019) Penicillium section Lanata-divaricata from acidic soil. Cladistics : The International Journal of the Willi Hennig Society 35(5): 514–549. https://doi.org/10.1111/cla.12365 Díaz-González S, Andrés MF, González-Sanz C, Sacristán S, González-Coloma A (2025) Nematicidal and antifeedant activity of ethyl acetate extracts from culture filtrates of Arabidopsis thaliana fungal endophytes. Scientific Reports 15: 11332. https://doi. org/10.1038/s41598-025-94939-6 Felsenstein J (1985) Confidence limits on phylogenies: An approach using the bootstrap. Evolution; International Journal of Organic Evolution 39(4): 783–791. https://doi. org/10.2307/2408678 Gaynes R (2017) The discovery of penicillin—New insights after more than 75 years of clinical use. Emerging Infectious Diseases 23(5): 849–853. https://doi.org/10.3201/ eid2305.161556 Glass NL, Donaldson GC (1995) Development of primer sets designed for use with the PCR to amplify conserved genes from filamentous ascomycetes. Applied and Environmental Microbiology 61(4): 1323–1330. https://doi.org/10.1128/aem.61.4.1323-1330.1995 Haranto T, Khunnamwong P, Wongkamhaeng K, Lueangjaroenkit P (2024) Exophiala amphawaensis sp. nov., a novel black yeast isolated from the gut of amphipods in Thailand. International Journal of Systematic and Evolutionary Microbiology 74(5): 006363. https://doi.org/10.1099/ijsem.0.006363 Hong SB, Cho HS, Shin HD, Frisvad JC, Samson RA (2006) Novel Neosartorya species isolated from soil in Korea. International Journal of Systematic and Evolutionary Microbiology 56(2): 477–486. https://doi.org/10.1099/ijs.0.63980-0 Houbraken J, Samson RA (2011) Phylogeny of Penicillium and the segregation of Trichocomaceae into three families. Studies in Mycology 70(1): 1–51. https://doi. org/10.3114/sim.2011.70.01 Houbraken J, Lopez-Quintero CA, Frisvad JC, Boekhout T, Theelen B, Franco-Molano AE, Samson RA (2011) Penicillium araracuarense sp. nov., P. elleniae sp. nov., P. penarojense sp. nov., P. vanderhammenii sp. nov. and P. wotroi sp. nov., isolated from leaf litter. International Journal of Systematic and Evolutionary Microbiology 61(6): 1462–1475. https://doi.org/10.1099/ijs.0.025098-0 Houbraken J, Kocsubé S, Visagie CM, Yilmaz N, Wang XC, Meijer M, Kraak B, Hubka V, Bensch K, Samson RA, Frisvad JC (2020) Classification of Aspergillus, Penicillium, Talaromyces and related genera (Eurotiales): An overview of families, genera, subgenera, sections, series and species. Studies in Mycology 95: 5–169. https://doi. org/10.1016/j.simyco.2020.05.002 Ifunanya RA, Ikenna VC, Emmanuel CO, Francis AG, Deborah OE, Oge NO (2023) Penicillium species as chassis for biomanufacturing and environmental sustainability in the modern era: Progress, challenges, and future perspective. Fungal Biology Reviews 46: 100326. https://doi.org/10.1016/j.fbr.2023.100326 Jones EBG (2011) Are there more marine fungi to be described? Botanica Marina 54(4): 343–354. https://doi.org/10.1515/bot.2011.043 Kornerup A, Wanscher JH (1967) Methuen Handbook of Colour. 3rd ed. Methuen & Co. Ltd., London, 252 pp. Lee NLY, Huang D, Quek ZBR, Lee JN, Wainwright BJ (2019) Mangrove-associated fungal communities are differentiated by geographic location and host structure. Frontiers in Microbiology 10: 2456. https://doi.org/10.3389/fmicb.2019.02456 Leetanasaksakul K, Roytrakul S, Kittisenachai S, Lohmaneeratana K, Jantasuriyarat C, Lueangjaroenkit P (2024) Exploring the impact of endophytic fungus Aspergillus cejpii 237 MycoKeys 126: 213–238 (2025), DOI: 10.3897/mycokeys.126.172211 Vassana Supapongsri et al.: New Penicillium and Thai record of P. danzhouense with antibacterial activity DMKU-R3G3 on rice: Plant growth promotion and molecular insights through proteomic analysis. Agronomy (Basel) 14(3): 498. https://doi.org/10.3390/agronomy14030498 Liu YJ, Whelen S, Hall BD (1999) Phylogenetic relationships among ascomycetes: Evidence from an RNA polymerase II subunit. Molecular Biology and Evolution 16(12): 1799–1808. https://doi.org/10.1093/oxfordjournals.molbev.a026092 Liu C, Wang XC, Yu ZH, Zhuang WY, Zeng ZQ (2023) Seven new species of Eurotiales (Ascomycota) isolated from tidal flat sediments in China. Journal of Fungi 9(10): 960. https://doi.org/10.3390/jof9100960 Lv F, Zeng Y (2024) Novel Bioactive Natural Products from Marine-Derived Penicillium Fungi: A Review [2021–2023]. Marine Drugs 22(5): 191. https://doi.org/10.3390/md22050191 Mousa AA, Abouelela ME, Al Ghamidi NS, Abo-Dahab Y, Mohamed H, Abo-Dahab NF, Hassane AMA (2024) Anti-Staphylococcal, anti-Candida, and free-radical scavenging potential of soil fungal metabolites: A study supported by phenolic characterization and molecular docking analysis. Current Issues in Molecular Biology 46(1): 221–243. https://doi.org/10.3390/cimb46010016 Nóbrega JP, do Nascimento Barbosa R, Lima JMS, de Medeiros Bento D, de Souza-Motta CM, Melo RFR (2024) Six new Penicillium species in the section Lanata-Divaricata from a cave in Amazon rainforest, Brazil. Mycological Progress 23: 71. https://doi. org/10.1007/s11557-024-02007-6 Norphanphoun C, Jayawardena RS, Chen Y, Wen TC, Meepol W, Hyde KD (2019) Morphological and phylogenetic characterization of novel pestalotioid species associated with mangroves in Thailand. Mycosphere : Journal of Fungal Biology 10(1): 531–578. https://doi.org/10.5943/mycosphere/10/1/9 Pitt JI (1980) The Genus Penicillium and its Teleomorphic States Eupenicillium and Talaromyces. Academic Press, London, 634 pp. Rodriguez-Andrade E, Stchigel AM, Cano-Lira JF (2021) New xerophilic species of Penicillium from soil. Journal of Fungi (Basel, Switzerland) 7(2): 126. https://doi. org/10.3390/jof7020126 Ropars J, Didiot E, Rodríguez de la Vega RC, Bennetot B, Coton M, Poirier E, Coton E, Snirc A, Le Prieur S, Giraud T (2020) Domestication of the emblematic white cheese-making fungus Penicillium camemberti and its diversification into two varieties. Current Biology : CB 30(22): 4441–4453.e4. https://doi.org/10.1016/j.cub.2020.08.082 Shaaban R, Elnaggar MS, Khalil N, Singab ANB (2023) A comprehensive review on the medicinally valuable endosymbiotic fungi Penicillium chrysogenum. Archives of Microbiology 205(6): 240. https://doi.org/10.1007/s00203-023-03580-2 Stolk AC, Scott DB (1967) Studies on the genus Eupenicillium Ludwig I. Taxonomy and nomenclature of Penicillia in relation to their sclerotioid ascocarpic states. Persoonia - Molecular Phylogeny and Evolution of Fungi 4(4): 391–405. Tamura K, Stecher G, Kumar S (2021) MEGA11: Molecular evolutionary genetics analysis version 11. Molecular Biology and Evolution 38: 3022–3027. https://doi.org/10.1093/ molbev/msab120 Thitla T, Monkai J, Meng W, Khuna S, Xie N, Hongsanan S, Lumyong S (2025) Two new species of Penicillium and a new genus in Xylariomycetidae from the forest dump-sites in Chiang Mai, Thailand. MycoKeys 116: 275–301. https://doi.org/10.3897/mycokeys.116.150635 Thom C (1930) The Penicillia. The Williams & Wilkins Company, Baltimore. Udagawa SI, Horie Y (1973) Some Eupenicillium from soils of New Guinea. Nippon Kingakkai Kaiho 14: 370–387. Visagie CM, Hirooka Y, Tanney JB, Whitfield E, Mwange K, Meijer M, Amend AS, Seifert KA, Samson RA (2014) Aspergillus, Penicillium and Talaromyces isolated from house