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Fishery Bulletin 102(3) 



most similar to pygmy rockfish (0.25-0.83%; Fig. 3B). 

 Increased levels of interspecific nucleotide variation, 

 attributable to the faster evolving control region, re- 

 sulted in more pronounced differences between the four 

 specimens and the other species of Sebastes within the 

 subset (range: 0.83-3.00%; Fig. 3B). Additionally, a 

 distance-based analysis (UPGMA) of haplotypes (cyt- 

 fr+CR) clustered all four specimens with pygmy rockfish 

 reference material. 



Discussion 



Postflexion larval pygmy rockfish can be identified 

 through a combination of pigment and meristic char- 

 acters. At approximately 8-10 mm, the larval pigment 

 pattern is similar to only four of the 30 Sebastes spe- 

 cies illustrated in the literature that occur within our 

 geographic area (Matarese et al., 1989; Moser, 1996; 

 Laroche 1 ): yellowtail (S. flavidus), blue (S. mystinus), 

 canary (S. pinniger), and sharpchin rockfish. Yellowtail 

 and blue rockfish can be separated from pygmy rockfish 

 because they exhibit ventral body and hypural pigment 

 at this size — pigment that does not show up in pygmy 

 rockfish until approximately 14 and 15 mm, respectively. 



In canary rockfish, the presence of ventral body pigment 

 and dorsal midline pigment posterior to the soft dorsal 

 fin (instead of at the base of the soft dorsal-fin rays as in 

 pygmy rockfish) can help differentiate this species from 

 pygmy rockfish. Pigmentation patterns of sharpchin 

 rockfish are very similar to pygmy rockfish at 10 mm; 

 however, sharpchin rockfish retain pigmented pelvic fins 

 until 12.7 mm (Laroche and Richardson. 1981). Counts of 

 anal-fin rays often can be used to differentiate these two 

 species because pygmy rockfish have six rays and sharp- 

 chin have rockfish seven rays (Chen, 1986; Matarese et 

 al., 1989; Moreland and Reilly, 1991; Laroche 1 !. There 

 is a small overlap in anal-fin ray counts (approximately 

 1' i I, and, because of this, 100% certainty of identification 

 cannot be reached by anal-fin ray counts alone. There- 

 fore, in order to increase confidence in identifications, a 

 combination of pigmentation and fin-ray counts should 

 be employed. After approximately 15 mm. a full comple- 

 ment of fin rays and gill rakers typically is present and 

 can be used in combination with pigmentation patterns 

 to differentiate pygmy rockfish from most other rockfish 

 species. In these late-stage larvae, only three species 

 (yellowtail. black (S. melanops), and blue rockfish) have 

 a pigment pattern that could be confused with pygmy 

 rockfish (Matarese et al., 1989; Moser, 1996; Laroche 1 ). 



