Yuanjiang River (Red River) is one of the six major water systems in Yunnan Province, which originates from western Yunnan Province. This river system features numerous tributaries, complex terrain, and abundant natural resources. During the investigation on the diversity of lignicolous freshwater fungi in the Yuanjiang River, nine species were collected and identified, five belonging to Dothideomycetes and four to Sordariomycetes. Based on morphology and multigene phylogenetic analyses, four species, namely, Aquadictyospora aquatica, Dictyosporium fluminicola, Myrmecridium submersum, and Neomyrmecridium fusiforme, are described as new species. Dictyocheirospora aquadulcis is reported as a new national record, and Myrmecridium hydei is reported as a new habitat record. Dictyocheirospora rotunda, Halobyssothecium aquifusiforme, and Pseudohalonectria lutea were known earlier from freshwater habitats, but we described them in detail in this paper. This study contributes significantly to the understanding of the diversity of lignicolous freshwater fungi in southwestern China.

Persistently high levels of abiotic stress define extreme environments. Even for adapted extremophiles, we argue this stress remains a continuous physiological challenge, necessitating energetically costly homeostasis. Crucially, this persistent pressure drives a self-reinforcing feedback loop across biological scales: it accelerates genomic evolution and concurrently reshapes ecological network architecture. Genomic innovations provide new traits for network reconfiguration, while the restructured network acts as a selective filter guiding subsequent evolution. This loop underpins extreme ecosystem resilience—the capacity for stress-induced adaptive restructuring. We synthesize mechanisms of this stress-adaptation interplay, propose testable hypotheses and outline experimental evolution approaches to validate this predictive framework for microbial responses to global change.