Figure 



28. — Length frequency of the Caribbean spiny 

 lobster (P. argus ). 



Figure 29. — Weight frequency of the Caribbean spiny 

 lobster (P. argus ). 



Pacific Sand Lobster (Evibacus princeps) 



E. princeps belongs to a family of crustaceans 

 composed of at least eight genera that have a 

 worldwide distribution. E. princeps has been 

 reported from lower California to Ecuador 

 (Rathbun, 1910). It has been called by an 

 assortment of common names such as sand 

 lobster, rock lobster, shovel lobster, Spanish 

 lobster, and bulldozer. On the Pacific side of 

 Panama it is usually referred to locally as the 

 Chinese lobster. 



There is little indication that sand lobsters 

 are used commercially in the Western Hemi- 

 sphere. This might result from either un- 

 familiarity with its edibility or its unavail- 

 ability in commercial quantities. In the Gulf 

 of Mexico, a sand lobster ( Scyllarus nodifer )is 

 occasionally taken in shrimp and fish trawls; 

 few are caught and the fishermen eat them 

 all. E_. princeps is available in commercial 

 quantities in Panama and is caught regularly 

 in the trawls of the local shrimp fishermen. 

 Because no local or export market exists, 

 however, the fishermen throw it back in the 

 water. 



The sand lobster is distinctly different in 

 appearance from the spiny lobster (fig. 15). 

 Its heavy, rigid shell is more depressed than 

 that of the spiny lobster and its last two sets 

 of legs, when extended, reach only slightly 

 beyond the edge of the carapace. Its bilobed 

 antennae are short and flattened and are as 

 wide as the anterior portion of the head. The 

 outer margins of the antennae are rounded. 

 It is from these appendages that some of the 

 common names such as shovel lobster and 

 bulldozer are derived. 



The same characteristics for the identifica- 

 tion of the sexes which were given for the 

 spiny lobster are true for the sand lobster. 

 The genital duct opening for the male is at the 

 base of the fifth pair of legs and for the female 

 at the base of the third pair of legs. The 

 swimmerettes of the male are small and do not 

 overlap while the female swimmerettes are 

 large and do overlap. 



The larval development has been described 

 for a related species, S. arctus , as reported by 

 Gurney (1942), and closely parallels the larval 

 development of the spiny lobster. However, 

 the extremely limited amount of study devoted 

 to this family of lobsters prevents any com- 

 prehensive discussion of their life history. 



The weight-length relation of the male and 

 female sand lobster shows that the female, 

 after it reaches a weight of 5 to 6 ounces, 

 becomes larger and heavier than a male of the 



24 



