Limin Yang

Underground coal extraction alters aquatic ecosystems. Quantitative evaluation of microbial responses serves as an indicator for ecological security. High-throughput amplicon sequencing and structural equation modeling were applied to analyze aquatic bacterial and fungal communities before and after operations at the Talahao coal mine. Mining activities correlated with altered physicochemical water properties and reduced microbial community evenness. Environmental variables, including ion accumulation and suspended solid concentrations, mediated the indirect effects of mining on microbial restructuring based on structural equation models. Taxonomic composition shifted across domains following extraction. Pre-mining bacterial communities contained higher proportions of the genera Devosia and Acidovorax. Post-mining bacterial communities experienced an enrichment of the genus Malikia and the family Methylomonadaceae. Pre-mining fungal communities included Cladosporium and Aspergillus. Post-mining fungal communities exhibited a subterranean response pattern dominated by unclassified lineages and taxa belonging to Basidiobolaceae diverging from surface soil reference frameworks. Functional predictions indicated divergent stability between the two domains. Bacterial inferred functional profiles remained stable despite taxonomic restructuring. Fungal assemblages underwent compositional shifts in trophic guilds. These data provide a baseline regarding the divergent functional stability between bacterial and fungal communities in water bodies before and after underground coal extraction and establish biological indicators for environmental assessment.

Gephyrocharax atracaudatus is a rare freshwater fish in Panama. This study provides a comprehensive analysis of the mitochondrial genome of G. atracaudatus, highlighting its gene composition, codon usage, evolutionary pressures, and phylogenetic relationships. The findings reveal unique evolutionary patterns and divergence times of G. atracaudatus that enhance the understanding of the genetic diversity within Characiformes. The increasing availability of genomic data has prompted taxonomic revisions for numerous Characiformes species, encompassing corrections to species names, subfamily, and family classifications. This study reconfirmed the classification of G. atracaudatus as “Gephyrocharax, Stevardiinae, Stevardiidae, Characiformes”. A cross-analysis model for species differentiation and tracking was established using divergence time comparison and phylogenetic analysis. The results show that G. atracaudatus, Hyphessobrycon roseus and Pristella maxillaris converge on one branch, indicating that the genetic relationship may be the most similar, and it occurred approximately 90.45 Mya in the Cretaceous. This study establishes a robust model framework for understanding the evolution of G. atracaudatus, and correctly determines the biological classification status of G. atracaudatus, providing basic data support for clarifying the evolution mode of Characiformes.

In the present study, the mitochondrial genomic characteristics of Acanthopsetta nadeshnyi have been reported and have depicted the phylogenetic relationship among Pleuronectidae. Combined with a comparative analysis of 13 PCGs, the TN93 model was used to review the neutral evolution and habitat evolution catalysis of the mitogenome to verify the distancing and purification selectivity of the mitogenome in Pleuronectidae. At the same time, a species differentiation and classification model based on mitogenome analysis data was established. This study is expected to provide a new perspective on the phylogenetic relationship and taxonomic status of A. nadeshnyi and lay a foundation for further exploration of environmental and biological evolutionary mechanisms.