RICHARDSON and LAROCHE: DEVELOPMENT AND OCCURRENCE OF ROCKFISHES 



mm. By 41.6 mm small external melanophores 

 cover all but the ventralmost one-fourth of the 

 abdominal region including most of the pectoral 

 fin base and the dorsal one-fourth of the gut re- 

 gion. The dorsal saddle and internal gut pigmen- 

 tation still appear as more darkly pigmented 

 areas. The caudal peduncle patch expands to the 

 dorsal and ventral body margins. Specimens >20 

 mm have a few melanophores extending an- 

 teriorly from the peduncle patch along the dorsal 

 body margin under the posteriormost dorsal rays. 

 By 41.6 mm the entire tail region of the body is 

 also covered with small external melanophores, 

 although the caudal peduncle patch and dorsal 

 midline melanophores remain visible. Pectoral 

 and pelvic fins lose all pigment by 41.6 mm, except 

 for a patch of small melanophores on the base of 

 the central pectoral rays. The spinous dorsal fin 

 becomes completely covered with small melano- 

 phores by 41.6 mm and small melanophores cover 

 the proximal one-fourth of the soft dorsal fin. 

 Small melanophores extend onto the bases of the 

 caudal fin rays by 41.6 mm. 



Melanistic pigment is inconspicuous on the 

 benthic juveniles examined. 136 and 183 mm. The 

 caudal peduncle pigment patch is no longer visi- 

 ble. 



Occurrence (Figures 14, 15). — Sebastes hel- 

 vomaculatus ranges from Coronado Bank, off San 

 Diego, Calif, to Albatross Bank, Gulf of Alaska, 

 and occurs in depths from 133 to 456 m (Chen 

 1971). It is apparently primarily a deepwater 

 species judging by some of the older common 

 names given to it, "deep-water scacciatale" and 



"deep-water scratch-tail" (Phillips 1957). The 

 largest numbers and smallest larvae were taken 

 83 and 120 km off Newport beyond the continental 

 shelf break. Most pelagic juveniles were taken at 

 the same locations as the larvae, probably reflect- 

 ing the increased sampling effort in that area. One 

 benthic juvenile, 136 mm, was taken in an otter 

 trawl at a depth of 370 m (lat. 44°47.9' N, long. 

 124°40.9' W). A second juvenile, 183 mm, was col- 

 lected after a seismic profiling explosion on 

 Stonewall Bank ( =lat. 44°30' N, long. 124°25' W). 



JUL 



I 1 1 ihX- 



AU6 



J. 



X-L 



SEP 



OCT 



NOV 



JlL 



-4- 



20 



to 60 80 100 120 140 180 190 



Standard Length (mm) 



Figure 15. — Seasonal occurrence of larvae and juveniles of 

 Sebastes helvomaculatus off Oregon, Data from 1961 to 1976 

 combined. Dashed line separates pelagic and benthic stages. 



FIGURE 14. — Number of specimens and location of capture of larvae and juveniles of Se6as^es helvomaculatus off Oregon (1961-76) 



described in this paper. 



37 



