Research Publication Details

Abstract

Abstract Akanthomyces Lebert belongs to the family Cordycipitaceae (Hypocreales, Sordariomycetes), which is regarded as one of the most important groups of entomopathogenic fungi (EPF). Despite the high fungal diversity in Sabah, Malaysia, the systematics and phylogeny of Akanthomyces in this region is still lacking. This study aimed to characterize entomopathogenic fungal specimens collected from Sabah using morphological and molecular phylogenetic approaches to determine their taxonomic status. During surveys of entomopathogenic fungi, two specimens infecting lepidopteran host were collected and examined using morphological characterization and molecular phylogenetic analyses. Five genetic markers, including the internal transcribed spacer (ITS) region, small subunit ribosomal RNA (SSU), translation elongation factor 1-alpha (TEF1-α), RNA polymerase II largest subunit (RPB1), and RNA polymerase II second largest subunit (RPB2), were amplified and sequenced to infer phylogenetic relationships. Phylogenetic analyses were conducted using Maximum Likelihood (ML) and Bayesian Inference (BI) based on individual and concatenated datasets (ITS–SSU–TEF1-α-RPB1–RPB2). The analyses consistently recovered the Bornean isolates as a distinct, well-supported lineage. Morphologically, the isolates are distinguished by robust, cream to pale-yellow branched synnemata, smaller perithecia, larger ellipsoidal conidia and filiform, multiseptate ascospores that disarticulate at maturity into cylindrical to slightly barrel-shaped part-spores at maturity compared with closely related species. Based on the combined morphological and phylogenetic evidence, Akanthomyces infaproensis sp. nov. is described from Sabah, Malaysia. The discovery of this new species expands the known diversity of Akanthomyces and highlights the tropical rainforests of Sabah as reservoirs of undescribed fungal diversity. Key words: Lepidoptera, molecular phylogeny, Sabah, taxonomy, new taxa