PRELIMINARY NOTES ON ZOEA AND MEGALOPA OF THE GIANT SPIDER CRAB, MACROCHEIRA KAEMPFERI DE HAAN

Hidetomo Tanase
1967 Publications of the Seto Marine Biological Laboratory  
The giant spider crab, Macrocheira kaempfiri, is the biggest member of all recent Arthropoda and inhabits only the deep waters, ranging 50 to 200 m, off the Pacific coast of Japan. In early spring, a noticeable number of mature individuals come up to shallower place of the southeastern coast of the Kii Channel near our laboratory and are often caught by trawl or trammel nets. Very probably these giant spider crabs belong to the spawning migratory population, because many of captured carbs
more » ... aptured carbs display copulation in the aquarium and most of females collected in the early season are holding eggs. So far as I am aware, the life history of this crab is yet quite unknown except for AIKAWA's paper (1941) which presents the description and figures of its first stage zoea. Fortunately I had some chances to observe the hatching out of larvae of this crab in the laboratory aquarium in these years. Then, I tried to rear those larvae under artificial conditions to contribute somewhat to the study of the life history of this huge crab. In the spring of 1966, about twenty newly hatched zoeae were reared and a single individual of them succeeded to attain the megalopa through two zoean stages. Again in this spring, three individuals of about 140 larvae were grown to the megalopa. Here in this paper, the characteristic features of these larvae are given together with some figures. I wish to express my hearty thanks to Messrs. Ch. ARAGA and S. NISHIMURA of the Seta Marine Biological Laboratory for their valuable advices to this work and also to Prof. H. UnNOMI and Dr. T. ToKIOKA of the Laboratory for their kindness in reading the manuscript. Material and Methods Several ovigerous females were obtained by trawl-net fishery off Minabe, about 5 kilometers north of the Laboratory. These females were kept and observed in a I)
doi:10.5134/175473 fatcat:wmyarmy6tfd3znjleepdaj65oi