Acheilognathus elongatus

The elongate bitterling, <em>Acheilognathus elongatus</em>, is a freshwater fish belonging to the family Acheilognathidae. It inhabits rivers and streams across East Asia, where it is associated with slow to moderate currents and substrates suitable for mussel hosts, as bitterlings are known for their unique reproductive strategy of depositing eggs inside freshwater bivalves. This species reaches a maximum recorded length of approximately 19.8 cm, making it one of the larger members of its genus. Like other acheilognathins, <em>Acheilognathus elongatus</em> typically feeds on algae, plant material, and small invertebrates. The species is native to freshwater systems in China, where it shares habitat with numerous cyprinid relatives. Seasonal variation in water temperature and flow influences its activity and reproductive behavior. Details of specific habitat preferences and precise geographic range for this species remain limited in the ichthyological literature.