Abstract <p>The life cycle features of European bitterling <i>Rhodeus amarus</i> from two ponds near the northeastern edge of the species' geographic range are studied. Several ontogenetic stages are described based on the free embryos and larvae obtained from the swan mussel <i>Anodonta cygnea</i> and reared at natural temperature, as well as on fishes collected in the wild. Following the emergence from the mussels in late June and July, the raised juveniles reach 23.3–24.5 mm fork length on September 9. The secondary sexual characteristics (conical organ in the ovipositor base in the females and red pigment in the anal fin in the males) appear in the juveniles and remain over the entire life of the fish. The fishes spawn from late April to mid-June releasing two main oocyte batches; the first batch contains 10–42 oocytes. Less than half of all oocytes are released during the current spawning season. After the spawning, vitellogenic oocytes are retained and continue to grow for the spawning season of the next year.</p>

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Life History of European Bitterling Rhodeus amarus (Acheilognathidae) in Two Ponds of Central Russia. 1. Ontogenetic Stages and Reproductive Cycle

  • D. A. Pavlov

摘要

Abstract

The life cycle features of European bitterling Rhodeus amarus from two ponds near the northeastern edge of the species' geographic range are studied. Several ontogenetic stages are described based on the free embryos and larvae obtained from the swan mussel Anodonta cygnea and reared at natural temperature, as well as on fishes collected in the wild. Following the emergence from the mussels in late June and July, the raised juveniles reach 23.3–24.5 mm fork length on September 9. The secondary sexual characteristics (conical organ in the ovipositor base in the females and red pigment in the anal fin in the males) appear in the juveniles and remain over the entire life of the fish. The fishes spawn from late April to mid-June releasing two main oocyte batches; the first batch contains 10–42 oocytes. Less than half of all oocytes are released during the current spawning season. After the spawning, vitellogenic oocytes are retained and continue to grow for the spawning season of the next year.