RICHARDSON and LAROCHE DEVELOPMENT AND OCCURRENCE OF ROCKFISHES 



smallest juvenile taken in a bottom trawl was 46.8 

 mm. 



Morphology (Tables 4, 5). — Measurements of var- 

 ious body parts were made on 53 selected speci- 

 mens of S. crameri, ranging from 8.0 to 130.5 mm 

 long, to examine developmental morphology. Rel- 

 ative body depth at the pectoral fin base and at the 

 anus increases somewhat, 32 to 34% SL and 24 to 

 28'7f SL, respectively, during development from 

 flexion larvae to benthic juveniles. A more marked 

 change occurs in snout to anus distance which 

 increases from 54 to 65'7f SL. The distance from the 

 snout to the pelvic fin base increases slightly. 



Head length decreases somewhat during de- 

 velopment from 39 to 369c SL, while major de- 

 creases occur in eye diameter (40-33% HL), upper 

 jaw length (56-41% HL), and interorbital distance 

 (36-23% HL). Snout length first increases slightly 

 and then decreases with respect to head length. 

 The length of the angle gill raker increases from 9 

 to 16% HL. 



Fin Development (Tables 3, 4, 5). — Pectoral fins 

 are formed in 8 mm larvae of S. crameri and the 

 adult complement of 18 to 20 (usually 19) fin rays 

 (or ray elements) are countable in 9 mm speci- 

 mens. The fins become more elongate with de- 

 velopment, increasing from 17% SL in flexion lar- 

 vae to a maximum of 32% SL in pelagic juveniles. 

 Depth of the pectoral fin base decreases from 13 to 

 10% SL. 



Pelvic fin buds are present on 8 mm lai'vae and 

 the forming spines and rays (1,5) can be counted in 

 9 mm larvae although they are not fully developed 

 until the larvae reach about 10 mm. Length of the 

 pelvic fins increased from 7 to 21% SL during the 

 larval and juvenile periods. Length of the pelvic 

 spine, which is less than the longest ray, increases 

 from 5%' SL in flexion larvae to 19% during trans- 

 formation, and then decreases to an average of 

 13% in benthic juveniles. 



In 8.0 mm larvae the adult complement of 8 -i- 7 

 principal caudal rays can be counted although 

 notochord flexion does not appear to be complete 

 until larvae are >9.3 mm. Counts of superior and 

 inferior secondary caudal rays made on one 

 stained juvenile, 38.2 mm, were 12 and 13, respec- 

 tively. 



Bases of some dorsal and anal fin rays and 

 spines are visible on 8 mm larvae. Development of 

 the second dorsal and anal soft rays occurs simul- 

 taneously with the central rays forming first and 



the posteriormost rays last. Developing soft ray 

 elements are visible and adult complements can 

 be counted on 9 mm larvae although rays do not 

 appear fully formed until larvae are >10 mm. 

 Dorsal spines begin to form slightly after initia- 

 tion of soft ray formation at =9 mm. The third, 

 fourth, and fifth dorsal spines develop first. The 

 12th spine is not formed until larvae are >13 mm 

 long. The second anal spine is formed at 10.6 mm 

 and the first is formed by 12 mm. The transition of 

 dorsal and anal fin "prespines" to spines is com- 

 plete at around 22 mm. The longest dorsal spine 

 increases from 22 to 45% HL during the pelvic 

 phase, and decreases to 37% in benthic juveniles. 

 The longestdorsal ray increases from 26 to 41-43% 

 HL during development. The longest anal spine 

 increases from 16 to 37 or 38% HL. 



Spination (Tables 4, 6). — Spines visible on the left 

 side of the head of an 8.0 mm larva of S. crameri 

 consist of the parietal; the second, third, and 

 fourth preopercular spines of the posterior series; 

 the first, second, and third preopercular spines of 

 the anterior series; the postocular; and the pterot- 

 ic. Another more developed 8.0 mm specimen has a 

 developing nuchal spine bump; the inferior post- 

 temporal; the first spine of the inferior infraorbital 

 series, and the first spine on the superior infraor- 

 bital series. 



The parietal spine is relatively short, averaging 

 6.5 to 6.6% HL in larvae and decreasing to 3.0% 

 HL in pelagic juveniles. The nuchal spine in- 

 creases in length from 1% HL in flexion larvae to 

 4% in postflexion and transforming specimens 

 then decreases to 3% in pelagic juveniles. Parietal 

 and nuchal spines begin to fuse near their bases at 

 10.7 mm, gradually fusing towards the tips until 

 in specimens >38 mm the parietal tip is no longer 

 visible. In benthic juveniles the nuchal and 

 parietal spines are fused and their relative lengths 

 are =2% HL; however, increased pigment and 

 musculature allowed measurement only from tip 

 to body junction. The parietal spine and ridge are 

 not serrated in larvae <9 mm. Serrations first 

 appear at the center of the parietal ridge at 9 mm 

 and persist until =39 mm. 



The posterior series of preopercular spines are 

 among the most prominent in the larvae. The first 

 through fifth spines of the series are present in 

 larvae >10 mm. The third spine of the series is the 

 largest, averaging 17 or 18% HL in larvae and 

 then decreasing to 7% HL in benthic juveniles. 

 Spines in the posterior preopercular series never 



11 



