International Journal of Aquaculture, 2025, Vol.15, No.2, 88-98 http://www.aquapublisher.com/index.php/ija 95 mapping morphological, physiological and ecological traits onto molecular phylogenetic trees, researchers can find out which characteristics are inherited from common ancestors (conservative evolution) and which are independently generated by different lineages (parallel or convergent evolution). Siluriformes fish show rich diversity in habitats (such as caves, rapids, seawater, etc.) and morphological characteristics (such as tentacles, blind, bony plates). With the help of a reliable phylogenetic framework, adaptive features that have evolved independently multiple times can be identified. For example, cave adaptation has appeared in unrelated lineages (such as the genus Cave Catfish in East Asia and the genus Blind Catfish in Africa), indicating that different catfish have evolved similar strategies under similar ecological pressures. For example, marine invasions occurred in at least two major lineages: the marine scorpion family and the catfish family, respectively. The phylogenetic tree shows that they come from two independent freshwater ancestors, reflecting the biogeographic response of convergent evolution (Vega and Wiens, 2012). These understandings all rely on accurate phylogenetic tree scaffolds, otherwise they are easily misled by surface similarities. 7.2 Speciation mechanisms and adaptive evolution In terms of biodiversity research and species conservation, the latest phylogenetic studies continue to reveal underestimated species diversity and phylogenetic diversity in Siluriformes fish. For example, the multiple evolutionary branches hidden in the genus Silurus mentioned above, as well as some populations neglected by traditional classification under the genus Whipcatus, represent genetic diversity units that actually exist but have not been named or valued. This is crucial for biodiversity conservation. Many catfish live in specific aquatic ecosystems. If cryptic species are not identified, they may face the risk of extinction without being noticed. Therefore, phylogenetic studies can guide us to re-evaluate the conservation value of species and populations (Shao et al., 2021). Identifying lineages with high evolutionary uniqueness (such as single-genus, single-species families or endangered genetically isolated species) through molecular systematics methods can help to formulate "evolutionarily significant" conservation priorities. For example, the discovery that the family of Forked Tongue Catfish is a phylogenetic sister of the American Catfish family and only one species remains suggests that this family and its species should be given higher conservation attention because their extinction will lead to the loss of an entire unique lineage. For example, for widespread species, independent management units should be determined based on genetic differentiation. For example, different cryptic lineages of the genus Silurus should be treated as independent units in fishery management and conservation actions to maintain overall genetic diversity. 7.3 Applications of phylogenetic studies in endangered species conservation Phylogeny and taxonomic reconstruction can also directly serve the fishery and aquaculture industries. Accurate classification is the basis for aquaculture variety improvement and disease prevention and control. Some aquaculture objects that were misclassified in the past (such as the alien species "channel catfish" that was once farmed as native catfish) have been corrected through molecular identification, thus avoiding the ecological risks caused by species confusion (Yen et al., 2023). Understanding the relationship between closely related species can also help to utilize hybrid advantages for variety breeding and predict the possible impact of invasive alien species. From a taxonomic perspective, phylogenetic studies provide an objective basis for the revision of the classification system of Siluriformes fish. For example, based on the molecular phylogenetic tree, taxonomists have processed some paraphyletic groups and split or merged non-monophyletic taxa to make the classification reflect natural evolutionary relationships. This series of reconstruction work has made the classification of Siluriformes more stable and predictable, and also facilitated the communication of subsequent research. In this process, molecular evidence and traditional morphological evidence corroborate and complement each other: for most families and genera, the two types of evidence are consistent (increasing confidence); for the few cases of conflict, in-depth research is prompted to find out the cause, either morphological misjudgment or molecular tree misleading, thereby advancing cognition. It can be said that the process of classification reconstruction is also a process of deepening the understanding of the evolution of the catfish family. 8 Concluding Remarks The large-scale mitochondrial genome analysis not only verifies many traditional classification hypotheses (such
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