Abstract
Postlarvae of the genus Penaeus were collected with the aid of light attraction inside Ohara fishing port, Chiba Prefecture, Japan, from May to October, over a 3-year period, 1982-1984. A total of 1,130 individuals were collected consisting of three species. Among them, postlarvae of P. japonicus were by far the most dominant species representing 93.5% of the total catch, followed by P. semisulcatus (3.8%) and P. monodon (2.7%), and their modal carapace lengths were 1.7, 1.7 and 2.6 mm, respectively. A period of their major occurrence was from mid-July to mid-September.
