LARVAL DEVELOPMENT IN LABORATORY OF CANCER AMPHIOETUS RATHBUN, IN COMPARISON WITH THOSE OF SEVEN OTHER SPECIES OF CANCER (DECAPODA, BRACHYURA)

Abstract

Recently the larval development has been described in detail successively in the following seven species of Cancer (Decapoda, Brachyura): Cancer magister Dana, C. productus Randall, C. gracilis Dana, C. antennarius Stimpson and C. anthonyi Rathbun from the Pacific coast of North America and C. irroratus Say and C. borealis Stimpson from the Atlantic coast of North America (Poole, 1966; Trask, 1970; Ally, 1975; Roesijadi, 1976; Sastry, 1977a, b; Anderson, 1978). Cancer amphioetus Rathbun used for the present study is a dweller on the Pacific coast of Hokkaido, North Japan. The first zoea of this species has been observed already under laboratory conditions (Iwata, 1973). In the present study, the complete larval development including five zoeal stages and a megalopa are described in detail and the larval characters in the present species are compared with those in seven Cancer species hitherto reported.