LAROCHE and RICHARDSON: DEVELOPMENT AND OCCURRENCE OF ROCKFISHES 



Figure 3. — Pelagic juvenile (46.8 mm) and benthic juvenile 173 mml of Sebastes flavidus. 



taken off Yaquina Bay (the area offshore of which 

 most larval and pelagic juvenile S. flavidus were 

 collected), 96% had a pectoral fin ray count of 18 on 

 one or both sides. Of 66 S. melanops taken in 

 Yaquina Bay and adjacent tidepool and shallow 

 subtidal locations (the area offshore of which most 

 larval and pelagic juvenile S. melanops were col- 

 lected), 95% had a pectoral fin ray count of 19 on 

 one or both sides. Mean numbers of lateral line 

 pores were 52.33 ±0.52 (95% confidence) iN = 48) 

 and 49.20 ±0.42 (95% confidence) {N = 66) on the 

 left side of S. flavidus and S. melanops, respec- 

 tively. No significant difference was found be- 

 tween counts made on the left and right sides for 

 either species. Two specimens of S./Za()idus had 19 

 pectoral fin rays on both sides but lateral line 

 pores numbered -50 on both sides. Three speci- 

 mens of S. melanops had 18 pectoral fin rays on 

 both sides but lateral line pores numbered <51 on 

 both sides. Thus the number of pectoral fin rays 

 and lateral line pores allow positive identification 



of S. flavidus in most cases. Although diagonal 

 scale rows below the lateral line were not used in 

 making the initial identifications, they are useful 

 when they can be counted and can help verify 

 identifications when other characters are not con- 

 clusive (see Appendix Table 1). 



Specimens of S. flavidus and S. melanops were 

 selected for the developmental series only if pec- 

 toral fin ray counts on both sides were =sl8 and 

 55 19, respectively, to minimize possible confusion. 

 The presence of discrete melanophores at the ar- 

 ticulation of dorsal and anal fin soft rays and 

 melanophores along the posterior margin of the 

 hypural plate together with counts helped link the 

 developmental series and distinguish the speci- 

 mens from all other Oregon species. The more 

 slender and longer caudal peduncle of S. flavidus 

 and the deeper, shorter caudal peduncle of S. 

 melanops (Table 2) helped tie each series together, 

 confirm identifications, and eliminate confusion 

 between the two species. 



905 



