Abstract. -Reproduction of the 

 false southern king crab (Paralomis 

 granulosa) in two localities of the 

 Beagle Channel, Argentina, was 

 studied by monthly trap sampling 

 during 1989 and 1990. Size at go- 

 nadal maturity in males (50.2-mm 

 cephalothoracic length, CL) and fe- 

 males (60.6-mm CL) was signifi- 

 cantly less than size at morphomet- 

 ric maturity (57.0-mm CL in males; 

 66.5-mm CL in females). Embryonic 

 development lasted 18-22 months. 

 During this period, there was appar- 

 ently a 10-12 month diapause. In 

 one of the two localities, develop- 

 ment of eggs in a given clutch was 

 very heterogeneous, suggesting si- 

 multaneous occurrence of eggs with 

 12- and 22-month development pe- 

 riods. Larval hatching took place 

 mainly during winter. Female P. 

 granulosa molted during November 

 and mated immediately after. Bien- 

 nial reproduction was detected on 

 the basis of ovarian and embryonic 

 development, and on the basis of 

 shell condition. Thus, two different 

 female groups occur in the popula- 

 tion of the Beagle Channel. Fecun- 

 dity increases with size (1,441 to 

 8,110 eggs per female) and is sig- 

 nificantly less at the end than at the 

 start of embryogenesis. Ovaries and 

 brood each represented at most 6- 

 l r 7i of body weight. Paralomis granu- 

 losa is the only representative of its 

 genus that inhabits shallow water 

 and apparently retains some re- 

 productive features of its deep- 

 water relatives. 



Reproductive biology of the false 

 southern king crab [Paralomis 

 granulosa, Lithodidae) in the 

 Beagle Channel, Argentina 



Gustavo A. Lovrich 



Consejo Nacional de Investigationes Cientificas y Tecnicas (CONICET) 



Centra Austral de Investigaciones Cientificas (CADIC) 



CC 92, 94 1 Ushuaia, Tierra del Fuego, Argentina 



Present Address Maurice Lamontagne Institute, Invertebrates and 



Biostatistics Division, 850 Route de la Mer, PO Box 1 000, Mont Joli, 



Quebec G5H 3Z4, Canada 



Julio H. Vinuesa 



Consejo Nacional de Investigationes Cientificas y Tecnicas (CONICET) 

 Centra Austral de Investigaciones Cientificas (CADIC) 

 CC 92, 94 1 Ushuaia, Tierra del Fuego, Argentina 



Manuscript accepted: 11 May 1993. 

 Fishery Bulletin: 91:664-675 1 1993 1. 



Crabs of the genus Paralomis are 

 lithodids that inhabit the Atlantic, 

 Indian, and Pacific Oceans, ranging 

 in depth from 5 to 4152 m. The 

 false southern king crab, or centollon 

 in Spanish, Paralomis granulosa 

 (Jacquinot, 1847), inhabits the Pa- 

 cific Ocean from Paso Tenaun (Chile; 

 40° S) to Cape Horn, and the Atlantic 

 Ocean from 56° S to the Golfo San 

 Jorge (Argentina; 47°S) including the 

 Islas Malvinas (Falkland Islands) at 

 depths of up to 50 m (Macpherson, 

 1988). 



Paralomis granulosa and the 

 southern king crab (Lithodes 

 santolla) constitute the main crusta- 

 cean fisheries off the southern tip of 

 South America. Commercial exploi- 

 tation of P. granulosa started in the 

 early 1970's. The largest catches were 

 recorded in 1986 and amounted to 

 1,300 metric tons for Argentina and 

 Chile. In Argentina, during the last 

 three years, the yield of P. granulosa 

 was at least twice as great as that of 

 L. santolla. Although commercial 

 fishing for P. granulosa began more 

 than 15 years ago, studies on the life 

 history of this species are few. Man- 

 agement studies were conducted in 



Chile which resulted in fishing regu- 

 lations, such as a minimum legal size 

 and gear restrictions (Campodonico 

 et al., 1983). There is virtually no 

 information on the life cycle of P. 

 granulosa in South America, except 

 for reports on larval development 

 (Campodonico and Guzman, 1981), 

 larval ecophysiology (Vinuesa et al., 

 1989), and diets of juveniles and 

 adults (Comoglio et al., 1990). 



In this study we document aspects 

 of the reproductive biology of P. 

 granulosa, from data collected dur- 

 ing monthly sampling in the Beagle 

 Channel during 1989 and 1990. 

 Data on the reproductive cycle, fe- 

 cundity, embryogenesis, and other life 

 history traits were examined to ac- 

 quire basic information on the biol- 

 ogy of this commercially valuable 

 species. 



Materials and methods 



The fishing area was located along 

 the Beagle Channel between Lapa- 

 taia Bay (west) and the Moat Chan- 

 nel (east) (Fig. 1): fishing depths 

 ranged from 10 to 60 m. The Beagle 



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