Atypical Autumn Spawning of Smooth Lumpsucker Aptocyclus ventricosus (Cyclopteridae) in Peter the Great Bay (Sea of Japan)

For the first time, a case of autumn spawning has been recorded for the smooth lumpsucker Aptocyclus ventricosus. Larvae were caught in the Zhitkov Bay (Peter the Great Bay, Sea of Japan). A comparison of larvae with similar-sized individuals described earlier from other habitats is given, hatching and spawning dates are calculated in the considered hydrological conditions, and possible reasons are considered for the transition of this species from the usual spring spawning in this region to autumn spawning.