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Fishery Bulletin 94(2). 1996 



tween 100-149 fathoms off the central California 

 coast (Gunderson and Sample, 1980). This study de- 

 scribes the development of S. saxicola from pre-ex- 

 trusion larvae to the pelagic juvenile stage and de- 

 scribes the age and growth of larval S. saxicola. 



Methods 



Specimens of pelagic larval and juvenile S. saxicola 

 were obtained from cruises conducted aboard the 

 NOAA RV David Starr Jordan and the Moss Land- 

 ing Marine Laboratories RV Ed Ricketts. Specimens 

 were taken with Manta nets (0.505-mm mesh), bongo 

 nets (0.505-mm mesh), a 5-nr Methot-Isaacs-Kidd 

 (MIK) trawl (2-mm mesh and a 0.505-mm codend), 

 and a 26 x 26 m midwater trawl ( 12.7-mm stretched 

 mesh codend liner). Manta nets were used during 

 surveys in January and February 1992, bongo nets 

 in January and February 1992 and January 1994, 

 MIK trawls in March 1992 and 1993, and midwater 

 trawls in May and June 1990-93. Specimens taken 

 with Manta nets, bongo nets, and MIK trawls were 

 preserved in 95% EtOH, whereas specimens from 

 midwater trawls were frozen. Pre-extrusion larvae 

 were obtained from three adult females in February 

 1994 and preserved in 95% EtOH. All samples were 

 collected off central California between Cypress Point 

 (36°35'N) and Salt Point (38°35'N). 



We examined and measured 197 S. saxicola lar- 

 vae and juveniles from 3.3 mm notochord length (NL) 

 to 43.9 mm standard length (SL). Specimens greater 

 than 19.9 mm SL were identified by meristic charac- 

 ters (Chen, 1986; Matarese et al., 1989; Moreland 

 and Reilly, 1991; Laroche 4 ); melanophore patterns 

 were recorded. Specimens less than 20 mm SL were 

 initially identified by pigment patterns developed 

 from a size-series based on pre-extrusion pigment 

 patterns and patterns of the smallest positively iden- 

 tifiable individuals with complete meristic charac- 

 ters. Whenever possible, dorsal-, anal-, and pecto- 

 ral-fin ray counts and the number of gill rakers on 

 the first gill arch were recorded and subsequently 

 used in identifications. Gill-raker counts were taken 

 only on fish larger then 15 mm SL. 



We measured snout to anus length, head length, 

 snout length, eye diameter, body depth at the pecto- 

 ral-fin base, pectoral-fin length, pectoral-fin base 

 depth, and parietal spine length on 28 specimens from 

 3.3 mm NL to 20.9 mm SL. Terminology for morpho- 

 metries followed Richardson and Laroche ( 1979). 



4 Laroche, W. A. 1987. Guide to larval and juvenile rockfishes 

 iSebastes) of North America. Box 216, Enosburg Falls, VT 

 05450. Unpubl. manuscr., 311 p. 



Eighteen specimens from 6.2 mm NL to 20.9 mm 

 SL were stained with Alizarin Red S and examined 

 for head spination. Terminology for head spination 

 followed Richardson and Laroche ( 1979). 



Otoliths were removed from 58 S. saxicola larvae 

 (4.2 mm NL to 19.7 mm SL) and aged according to 

 procedures in Laidigetal. (1991). In addition, otoliths 

 from five species (S. atrovirens, S. auriculatus, S. 

 maliger, S. rastrelliger, and S. semicinctus) and two 

 species complexes (the copper complex \S. atrovirens, 

 S. carnatus, S. caurinus, and S. chrysomelas] and 

 the gopher complex [S. carnatus andS. chrysomelas]) 

 were removed for comparison of otolith characters 

 with S. saxicola (Laidig and Ralston, 1995). These 

 five species and two complexes were chosen for simi- 

 larity in pigment patterns with preflexion S. saxicola; 

 S. rastrelliger was also selected for its similar pig- 

 mentation in postflexion fish. In addition, otoliths 

 were removed and examined from 15 Sebastes lar- 

 vae of unknown species with pigment patterns simi- 

 lar to S. saxicola, but with pigment present on the 

 axillary surface of the pectoral fins. 



Results 



General development 



Larvae were extruded at a size of 3.3-5.2 mm NL. 

 Notochord flexion began at approximately 5.8 mm 

 NL and was completed by 8.0 mm SL. The full adult 

 complement of pectoral-fin rays developed during 

 late-stage flexion and early postflexion ( 16 rays, Table 

 1). By 7.0 mm NL, anal-fin rays had begun to form 

 and a full adult complement (7 rays, Table 1) was 

 present in 90% of the fish by 8.0 mm SL. The dorsal, 

 pectoral, and pelvic fins began to form around 7.5 

 mm NL and a full adult complement (dorsal= 12 rays, 

 pectoral=16, pelvic=5, Table 1) was present by ap- 

 proximately 9.0 mm SL. Lateral line pores first ap- 

 peared around 17 mm SL and a complete series was 

 apparent by approximately 38 mm SL. Because we 

 had only a few specimens above 38 mm SL, we were 

 unable to obtain accurate lateral line pore counts. 



Morphometries 



Changes in body shape in S. saxicola were related to 

 notochord flexion (Table 2). As the larvae began flex- 

 ion, they became more stout-bodied, as evidenced by 

 the increase in body depth at the pectoral-fin base. 

 During flexion, the pectoral-fin length increased as 

 the full adult complement of fin rays was attained 

 (Table 2). The parietal spine length increased until 

 approximately 10 mm SL when spine growth ap- 



