マツカサガイのグロキディウム幼生の流下生態
2004 年 54 巻 2 号 p. 85-94
詳細
2004 年 54 巻 2 号 p. 85-94
Seasonal and diel flow patterns of glochidia of the freshwater unionid mussel Pronodularia japanensis in a paddy field ditch were investigated by using drift nets (5×20cm frame, 0.113mm mesh). The glochidia were collected from May to September, maximally in July, mainly during the daytime and equally at both the surface and bottom layers of the study ditch. The flow distance was estimated to be less than about 180m. Dead glochidial shells were collected until October, equally during the day and night. Consequently, the use of drift nets was found to be valuable for investigating the flow patterns and spawning seasons of Pronodularia japanensis glochidia.
