full complement of 8 + 7 principal caudal rays is under- 

 going initial ossification in a larva 5.2 mm long. Second- 

 ary caudal rays begin ossifying in 5-mm larvae. In the 

 largest stained specimen (6.5 mm) there are 4 superior 

 and 4 inferior secondary elements ossifying. 



The pelvic fins appear when the larvae are about 4.0 

 mm long and increase in relative length to 10% of the 

 body length at the completion of notochord flexion. 

 There is a gradual elongation of the fin during later lar- 

 val stages to a maximum of 20% of the body length in our 

 largest larva. Pelvic fin rays begin ossifying in 5-mm lar- 

 vae and the full complement of 1 spinous ray and 5 soft 

 rays is ossifying before the larvae reach 6.0 mm. 



The dorsal and anal fins begin to form simultaneously 

 in larvae about 4.5 mm long. Ossification begins in 5-mm 

 larvae and the full complements of III, 5 or 6 anal rays 

 and XII, 8 to 10 dorsal rays is present in 6-mm larvae. 



Larvae of S. guttata are characteristically pigmented. 

 Pigmentation of larvae less than 3.0 mm long has been 

 described by other investigators and is summarized 

 above. Notable changes occur in the initial pigment pat- 

 tern in larvae larger than 3.0 mm. Melanophores first ap- 

 pear on the posterior margin of the pectoral fin in early 

 larvae and when the larvae are 3.2 mm long, the distal 

 half of the fin is covered. At 4.0-mm length, the entire fin 

 is covered with melanophores as is the medial surface of 

 the fin base. As the rays develop, the pigment becomes 

 restricted to the membrane between the rays and 

 becomes strikingly heavy. In 6-mm larvae the distal mai- 

 gin of each fin begins to lose pigment and this clear zone 

 widens to about 20% of the length of the fin in the largest 

 larva. Gut pigment was originally on the dorsolateral sur- 

 face of the gut, but spreads ventrally to cover all sur- 

 faces of the gut when the larvae reach 4.0 mm. There is a 

 gradual reduction in the number of pigment spots in the 

 ventral tail series. In larvae about 3.0 mm long the num- 

 ber of melanophores in this series ranges from 2 to 7 with 

 a mean of 4. 15 ± 1.62 SD for 50 larvae. In larvae between 

 3.0 and 8.0 mm there is a general decline in this number 

 but the average number for the whole size range is 

 2.64 ± 1.12 for 11 larvae. Larvae longer than 9.0 mm had 

 no ventral tail melanophores. 



When the larvae reach 4.0 mm, a small blotch of pig- 

 ment develops just anterior to the cleithral symphysis. 

 This remains throughout the larval period and is aug- 

 mented by several more melanophores in larvae larger 

 than 9.0 mm. Melanophores develop on the head region 

 in larvae of about 4.5 mm in length. A single melano- 

 phore is embedded at the nape and persists through the 

 remainder of the larval period. It is augmented by several 

 more melanophores in larvae 8.0 mm and longer. A pair 

 of melanophores appears above the optic lobes of the 

 brain in 4. 5-mm larvae and to these are added other 

 melanophores until the optic lobes are covered in larvae 

 larger than 9.0 mm. A pair of melanophores forms above 

 the olfactory lobes in larvae about 6.0 mm long and per- 

 sists throughout the remainder of the larval period. 

 Several melanophores form around the base of the pel- 

 vic fins in larvae about 6.0 mm long, but the fins them- 

 selves remain unpigmented until late in the larval 



period. Melanophores begin to form in the epaxial 

 myosepta above the pectoral fin in some larvae as small 

 as 6.2 mm and cover an extensive area in larvae larger 

 than 10.0 mm. Melanophores appear on the cheek and 

 below the eye in 9-mm larvae and become more exten- 

 sive in larger larvae. 



Distribution. — Adults of S. guttata are known from 

 Santa Cruz, Calif., southward to Uncle Sam Bank, Baja 

 California (about lat. 24°35'N). This species also occurs 

 at Guadalupe Island, Baja California, and in the 

 northern part of the Gulf of California (Miller and Lea 

 1972). Distribution of S. guttata larvae was analyzed for 

 the 1966 and 1969 CalCOFI cruises. Larvae were taken 

 from June to November in 1966 and from July to Sep- 

 tember in 1969. Spawning appears to peak in August, as 

 44% of the total occurrences and 67% of the larvae for 

 1966 were taken during this month (Table 34). 



Table 34. Numbers of occurrences and standardized numbers of larvae of 

 Scorpaena guttata taken by CalCOFI in 1966. 



Latitude of most shoreward station. 



Larvae of S. guttata occur in the southern portion of 

 the CalCOFI pattern, from about the Mexican border 

 south to line 137, just north of Magdalena Bay (Table 

 34). The greatest concentration of positive hauls was off 

 central Baja California in the area around Punta 

 Eugenia (Fig. 32). 



Scorpaena Type A, Figvire 33 



Literature. — This larval form of Scorpaena has not 

 been previously described or illustrated. 



Distinguishing features. — Egg masses of Scorpaena 

 species other than S. guttata have not been reported in 

 the eastern Pacific and yolk-sac stages of Type A larvae 

 are not present in our collection. Type A larvae are 

 similar morphologically to those of S. guttata, but are 

 comparatively more slender prior to notochord flexion. 

 Body depth at this stage averages 27% of body length for 

 Type A larvae (Table 35) and 36% for S. guttata. Body 

 depth for Type A larvae undergoing notochord flexion 

 averages 29% of body length, and for postflexion stages 

 the mean is 38%. Comparative percentages for S. gut- 

 tata larvae are 30% and 40%. 



57 



