Investigation on the Distribution of in Yuanshui Unique Fish Species National Aquatic Germplasm Resources Reserve Using Environmental DNA Technology.

Freshwater ecosystems face unprecedented challenges as the cumulative impact of human activities intensifies. While protected areas and species-specific conservation policies are widely implemented, their effectiveness remains difficult to gauge using traditional catch-based surveys. This research employed environmental DNA (eDNA) technology to assess the distribution of the endangered fish, , within the Yuanshui Unique Fish Species National Aquatic Germplasm Resources Reserve (YUFRR) in Hunan, China.

Formation of the synaptonemal complex in a gynogenetic allodiploid hybrid fish.

The correct pairing and separation of homologous chromosomes during meiosis is crucial to ensure both genetic stability and genetic diversity within species. In allodiploid organisms, synapsis often fails, leading to sterility. However, a gynogenetic allodiploid hybrid clone line (GDH), derived by crossing red crucian carp ( ♀) and common carp ( ♂), stably produces diploid eggs.

Immunoglobulin heavy-chain loci in ancient allotetraploid goldfish.

As an ancient allotetraploid species, goldfish (Carassius auratus) have two sets of subgenomes. In this study, immunoglobulin heavy-chain (IGH) genes were cloned from the red crucian carp (Carassius auratus red var.), and the corresponding loci were identified in the gynogenetic diploid red crucian carp (GRCC) genome as well as the genomes of three other goldfish strains (Wakin, G-12, and CaTCV-1).

A Novel Allotriploid Hybrid Derived From Female Goldfish × Male Bleeker's Yellow Tail.

Hybridization is a traditional and effective strategy to alter the genotypes and phenotypes of the offspring, and distant hybridization is a useful strategy to generate polyploids in fish. In this study, goldfish (, GF, 2n = 100) and Bleeker's yellow tail ( Bleeker, YT, 2n = 48), which belong to different subfamilies, were crossed with each other. The cross of female GF × male YT successfully obtained hybrid offspring (GFYT hybrids), while the cross of female YT × male GF was lethal, and all the fertilized eggs stopped developing before the neurula stage of embryogenesis.