抄録
Association of pontoniid shrimp, Periclimenes soror NOBILI, with four species of starfish was observed in the lagoon of Kuroshima Island (24°15′N, 124°O′E) during a period from April to September, 1985. Compositions of the carapace length of the shrimp were different by sex of the shrimp and host species. Females were generally larger than males. The females associated with the crown-of-thorns starfish, Acanthaster planci LINNE, were larger than the shrimps associated with other three starfish species. The color of the shrimp was divisible into four types. The females changed their color types with growth. On a host, at maximum 53 shrimps were observed, and the numbers of males and females of them were random. We released forty-nine tagged starfish without shrimps, and ten days after, recaptured the four starfish with ovigerous female shrimps. This result indicates that they move from one host to another. P. soror uses a starfish as a shelter, and probably eats mucus of the host. But, it seems that the association of P. soror with their host is not so close as that of other associated shrimps, such as coral associates.
