Prionospio ehlersi FAUVEL, 1928 (多毛類:スピオ科)の分布と生活史
1988 年 1988 巻 33-34 号 p. 25-31
詳細
1988 年 1988 巻 33-34 号 p. 25-31
TAMAI, KYOICHI (Nansei Regional Fisheries Research Laboratory, Kochi). 1988. Distribution and life history of Prionospio ehlersi FAUVEL, 1928 (Polychaeta: Spionidae) in Japan. Benthos Research (Bull. Jap. Assoc. Benthology), 33/34; 25-32. Prionospio ehlersi was a common spionid polychaete in benthic communities of soft bottom sediments ifl western Japan. It favoured the muddy or sandy mud sediment in oxidized environments, whereas it scarcely occurred at the areas with reduced conditions (D.O. saturation percentage of the bottom water was less than 50%). The population generally had a biased sex ratio to female (1:2), and the worms did not mature until they had grown into the body size with 0.38mm in the width of peristomium or 4.4mg in wet weight. This polychaete was annual species, and had a extended breeding season as a population. For example, in Tosa Bay, mature individuals with eggs or sperm were observed from April to November, and newly recruited individuals were collected from August to December. The egg size ranged from 95 to 105μm in diameter.
