RICHARDSON and LAROCHE: DEVELOPMENT AND OCCURRENCE OF ROCKFISHES 



spines develop, melanophores are added to the 

 nape patch along the dorsal midline and posteri- 

 orly along the dorsolateral body surface. The large 

 stellate melanophores extending from the nape 

 patch to the gut disappear by 12 mm. A few exter- 

 nal melanophores appear along the anterior mar- 

 gin of the middle of the cleithrum beneath the gill 

 cover in 12 or 13 mm larvae. 



In the tail region the ventral midline melano- 

 phores gradually become embedded, anterior ones 

 first, and are obscured by overlying musculature 

 by the time larvae are 13 mm long. A melanophore 

 is sometimes present near the tip of the notochord. 



The pigmentation of the paired fins increases m 

 intensity throughout the larval period, although 

 the di.stal base of the pectoral fin remains unpig- 

 mented. As the pelvic fins develop, melanophores 

 line the rays giving a striated appearance similar 

 to that of the pectoral fins. 



Melanophores appear on the anterior portion of 

 the spinous dorsal fin by the time larvae are 11 

 mm long, and the anterior two-thirds of the fin 

 remains rather heavily pigmented throughout 

 larval development. The soft dorsal and anal fins 

 remain unpigmented. 



One to several internal, vertically elongate 

 melanophores appear at the base of the caudal fin 

 posterior to the hypural elements on most larvae 

 >9 mm long, but the fin base is never completely 

 lined with pigment. 



During the transformation period, 16 to 21 mm, 

 pelagic juvenile pigmentation begins to develop. 

 On the head, pigment increases around the post- 

 temporal spines and joins with the nape pigment. 

 Internal and external melanophores are added on 

 the dorsal part of the opercle forming a patch 

 which expands ventrally on specimens >19 mm. 

 Scattered melanophores appear along the dorsal 

 surface of the snout and the anterior portion of the 

 upper lip (internal and external) on specimens 

 >18.5 mm long. Pigment increases around the 

 orbit, lining the dorsal, posterior, and ventral 

 margin of the orbit by 19 mm. In the abdominal 

 region, an increase in musculature over the gut 

 cavity obscures the internal gut pigment although 

 scattered external melanophores persist. The 

 nape patch extends anteriorly joining the head 

 pigment, laterally toward the body midline, and 

 posteriorly to the 12th dorsal spine. Two saddles of 

 intensified melanistic pigment begin to develop 

 beneath the first dorsal fin late in the transforma- 

 tion period. An anterior saddle joins the head pig- 

 ment and another saddle located midfin expands 



ventrolaterally. Melanophores are added dorsally 

 and ventrally along the anterior margin of the 

 cleithrum beneath the gill cover, eventually ap- 

 pearing as a line of pigment. In the tail region, 

 melanophores appear beneath the middle of the 

 second dorsal fin in 16 mm specimens. They ex- 

 pand anteriorly to join the pigment beneath the 

 spinous dorsal, posteriorly over the caudal pedun- 

 cle, and laterally towards the body midline ap- 

 pearing as a saddle by 20 mm. Some melanophores 

 at the base of the second dorsal fin become concen- 

 trated along muscles surrounding the dorsal 

 pterygiophores giving the appearance of vertical 

 lines of pigment by 20 mm. An additional 

 melanophore may appear at the point of articula- 

 tion of each dorsal soft ray 4 through 10 beginning 

 on 18 mm specimens. Pigment is added internally 

 and externally along the lateral midline of the 

 caudal peduncle. On the first dorsal fin pigmenta- 

 tion increases extending posteriorly to the 1 1th or 

 12th dorsal spine. 



In pelagic juveniles >22 mm long, small 

 melanophores appear over the surface of the head. 

 Melanophores almost entirely ring the orbit by 31 

 mm. Pigment increases on the snout and upper 

 and lower jaws. The two pigment saddles beneath 

 the first dorsal fin become more pronounced and 

 extend moi-e ventrolaterally. A third saddle forms 

 beneath the first dorsal fin posterior to the first two 

 in specimens about 22 to 25 mm long. In the tail 

 region, the saddle beneath the second dorsal fin 

 extends to the lateral midline by 24 mm and even- 

 tually reaches the ventral body margin in a 57 mm 

 specimen. The number of melanophores increases 

 on the caudal peduncle until dorsal and lateral 

 pigment are joined forming a fifth pigment saddle 

 in juveniles about 25 mm long. This fifth saddle 

 eventually extends to the ventral body margin as 

 does the saddle beneath the spinous dorsal fin. An 

 increase in the number of melanophores occurs 

 along the lateral midline of the caudal peduncle 

 giving the appearance of a distinguishable, but 

 not heavy, line of pigment. Small melanophores 

 are added between saddles 3 and 4 and 4 and 5, 

 along the myosepta first. The pectoral and pelvic 

 fins remain heavily pigmented, although the 

 amount of pigment on the base of the rayed portion 

 of the pectoral fin decreases. Pigmentation on the 

 spinous dorsal fin decreases in intensity between 

 spines III and V, and between spines VIII and IX, 

 corresponding to areas between the first, second, 

 and third pigment saddles on the body. On speci- 

 mens >38 mm long, pigment on the dorsal fin 



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