Two novel soil-derived Beauveria species from eastern China: integrative taxonomy and pathogenicity against Ostrinia furnacalis

Species delimitation in Beauveria is challenging because of conserved asexual morphologies and extensive cryptic diversity. Three soil-derived Beauveria isolates from Anhui, Jiangsu, and Shandong Provinces, China, were investigated using a concatenated four-locus dataset comprising ITS, Bloc, TEF , and RPB1 . Detailed cultural and microscopic morphological characterization was performed on GDMCC 3.1077 (AH08D02) and GDMCC 3.1078 (JS02A02), the designated type strains of the two proposed novel species. Their separation was further supported by differences in conidial dimensions and pairwise nucleotide sequence identities of 520/539 bp (96.47%; 12 gap positions) for ITS, 925/997 bp (92.78%; 52 gap positions) for Bloc, 250/263 bp (95.06%; 23 gap positions) for TEF , and 919/926 bp (99.24%; no gaps) for RPB1 between two strains. The concordance of multilocus phylogenetic placement, nucleotide differentiation, and microscopic morphological characteristics supports their recognition as two novel species, described here as Beauveria anhuiensis sp. nov. and B. shunxiangii sp. nov. Laboratory immersion bioassays against third-instar larvae of Ostrinia furnacalis demonstrated concentration-dependent mortality for both type strains. At 1 × 10 8 conidia/mL, day-9 mortality was nearly 100% for GDMCC 3.1077 and 90.0% for GDMCC 3.1078. The day-9 LC 50 were 0.763 × 10 6 and 2.018 × 10 6 conidia/mL for GDMCC 3.1077 and GDMCC 3.1078, respectively, while the corresponding LT 50 at 1 × 10 8 conidia/mL were 5.06 and 6.01 days. Although GDMCC 3.1077 yielded numerically lower lethal concentration and lethal time estimates, the overall difference in day-9 mortality between the two strains was not statistically significant. These findings demonstrate the pathogenic activity of both type strains under laboratory conditions and support their further evaluation as potential biological-control resources.