追おい星ぼし

noun

nuptial tubercles; breeding tubercles; pearl organs

Zoological term for small white bumps that appear on the skin of male fish during the breeding season, especially on the head and fins.

• 繁はん殖しょく期きのオイカワのオスには、頭とう部ぶに追おい星ぼしが現あらわれる。

  During the breeding season, male pale chub develop nuptial tubercles on their heads.

• 追おい星ぼしは、魚さかなの種しゅ類るいによって形かたちや分ぶん布ぷが異ことなる。

  The shape and distribution of nuptial tubercles vary depending on the fish species.