LAROCHE and RICHARDSON: DEVELOPMENT OF LARVAE AND JUVENILES OF ROCKFISHES 



40.1 mm 



Figure 3. — Pelagic juvenile (40.1 mm) and benthic juvenile (74.5 mm) of Sebastes entomelas. 



Laroche and Richardson (1980). Of 79 S. en- 

 tomelas examined 94% had dorsal fin rays ^15 and 

 96% had anal rays ^8. Of 62 S. mystinus 

 examined 92% had dorsal fin rays 2^16 and 90% 

 had & 9 anal fin rays. Only one specimen of S. 

 entomelas had >15 dorsal fin rays and >8 anal fin 

 rays. No S. mystinus had <16 dorsal fin rays and 

 <9 anal fin rays. In specimens with outlyer dorsal 

 or anal fin ray counts, the numbers of lateral line 

 pores and diagonal scale rows below the lateral 

 line resolved any questions in all cases (see 

 Laroche and Richardson 1980, appendix table 1). 

 To insure that no S. mystinus were accidentally 

 included in the developmental series of S. en- 

 tomelas, specimens with either >15 dorsal fin rays 

 or >8 anal fin rays were intentionally excluded. 



Pigment pattern and body morphology were 

 also useful in linking smaller specimens to the 

 developmental series. 



Distinguishing Features. — Characters useful to 

 distinguish S. entomelas larvae (9.9-18 mm) from 

 those of other Sebastes species are fin element 



counts, gill raker counts, moderate pigmentation 

 on pectoral and pelvic fins, presence of pigment 

 along the dorsal body surface beneath the dorsal 

 fin, internal and/or external melanophores above 

 the notochord near the point of flexion, and 

 melanophores along the dorsal and ventral mar- 

 gins of the caudal peduncle. The lack of 

 melanophores at the articulation of anal fin rays 

 helps distinguish S. entomelas from .S. flavidus 

 and S. melanops larvae within this size range. The 

 smaller caudal peduncle depth/caudal peduncle 

 length ratio and presence of 18 pectoral fin rays 

 also help to distinguish S. entomelas from S. 

 melanops. For larvae and juveniles >18 mm, 

 meristic characters, presence of preocular (speci- 

 mens >22 mm) and supraocular (specimens >18 

 mm) spines, flat to convex interorbital space, body 

 and fin pigmentation, and body morphometry to- 

 gether serve to distinguish S. entomelas from 

 other Oregon species. 



General Development. — Notochord flexion is com- 

 pleted by —14 mm in S. entomelas. Transformation 



235 



