TY - JOUR AU - Kotov, Alexey A. AU - Saeheng, Sompop AU - Maiphae, Supiyanit AU - Van Damme, Kay PY - 2013/10/18 Y2 - 2024/03/28 TI - Study of the embryogenesis of Dunhevedia crassa King, 1853 (Cladocera: Chydoridae) and a comparison of embryonic instar durations in different cladocerans JF - Journal of Limnology JA - J Limnol VL - 72 IS - 3 SE - Original Articles DO - 10.4081/jlimnol.2013.e47 UR - https://www.jlimnol.it/jlimnol/article/view/jlimnol.2013.e47 SP - e47 AB - <p class="p1"><em>The aim of this work is to study the embryonic development of a common tropical cladoceran </em>Dunhevedia crassa<em> King, 1853 (Anomopoda:</em><em>Chydoridae) and compare the durations of embryonic instars and growth during embryogenesis in small-sized chydorids and </em><em>other cladocerans. The sequence of events in the embryogenesis of </em>Dunhevedia<em> females was studied by means of i</em>n vitro<em> observation </em><em>in the laboratory at 28.5°C. We found that the general pattern of the sequence of events in chydorid embryogenesis is similar to that in </em><em>other anomopods. However, the relative durations of the embryonic instars I and II+III are markedly short, while that of instar IV is </em><em>long (delayed) when compared with other cladocerans. The observed pattern of ontogenesis in chydorids may therefore be apomorphic </em><em>within the cladocerans and could reflect a neotenic evolution. Another peculiar trait of </em>Dunhevedia<em> is the very small increase of the </em><em>size of the embryo during embryogenesis, which is correlated with a very large size of the egg relative to the mother. Therefore, our </em><em>study revealed some peculiarities in the ontogenesis of small-sized chydorids, which could be a result of family-specific evolution.</em></p> ER -