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Fishery Bulletin 98(2) 



forming specimens of the two 

 species (e.g. a longer serrate 

 third preopercular spine in S. 

 constellatus , more infraorbit- 

 als in S. ensifer only visible 

 after staining) may be due to 

 ontogenetic stage or individ- 

 ual variation (Table 3). How- 

 ever, the relatively longer fin 

 rays in S. ensifer appear to be 

 a species difference. The rel- 

 ative size and position of the 

 parietal and nuchal spines 

 differs in the two transform- 

 ing specimens; however, this 

 may be due to difference in 

 stage of development. In the 

 S. ensifer series the nuchal 

 spine gradually replaces the 

 parietal spine as the ter- 

 minus of the parietal ridge 

 and this may also occur in 

 S. constellatus. Transforming 

 specimens of the two species 

 differ slightly in pigmenta- 

 tion (e.g. wider dorsal saddle 

 and peduncle patch in S. ensi- 

 fer); however, this difference 

 can not be confirmed without 

 additional specimens. 



Transforming specimens and 

 pelagic juveniles of S. ensi- 

 fer and 5. helvomaculatus 



The species differ markedly 

 in morphometry (Table 1). 

 S. ensifer has a deeper-body 

 than field-caught S. helvo- 

 maculatus described and 

 illustrated in Richardson and 

 Laroche (1979), as shown by 

 the greater relative body 

 depth measured at the anus 

 (Table 1; Figs. 2 and 3). The 



two species are different in other morphometric fea- 

 tures. Eye diameter, jaw length, and fin ray and 

 spine lengths in the dorsal and anal fins are rela- 

 tively greater in transforming specimens and pelagic 

 juveniles of S. ensifer compared with S. helvomacu- 

 latus, whereas relative snout length is greater in S. 

 helvomaculatus. In pelagic juveniles, relative head 

 length is greater in S. helvomaculatus than in S. ensi- 

 fer, whereas relative interorbital length is less com- 

 pared with that in S. ensifer. The two species differ 

 in stage of development at length. The illustrated 



// / 



Figure 2 



Pelagic young of two species of Sebastes tSehastomust from localities off southern Cali- 

 fornia: (A) S. constellatus, transforming larva, 1.5.0 mm SL; (Bl S. ensifer, transforming 

 larva, 19.8 mm SL; (C) S. ensifer. pelagic juvenile, 27.3 mm SL. 



18.4-mm transforming specimen of S. helvomacu- 

 latus lacks a melanistic saddle on the trunk, and 

 the caudal peduncle bar is just beginning to form, 

 whereas these features are well established in the 

 19.8-mm specimen of S. ensifer (Figs. 2 and 3). The 

 pigment saddle is present in the 22.4-mm pelagic 

 juvenile of S. helvomaculatus but does not extend 

 ventrad more than about half-way to the lateral line. 

 Moreover, the complex pattern of bars and clear areas 

 present on late-stage pelagic juveniles of S. ensifer is 

 not present on S. helvomaculatus (Fig. 3). Also, the 



