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Fishery Bulletin 91(3), 1993 



agonids by Laroche (1986). For larvae with spines and 

 no named analogous adult spine, terminology follows 

 Moser and Ahlstrom ( 1978) or Richardson and Laroche 

 (1979) for larvae of rockfish Sebastes spp. (another 

 Scorpaeniform) (Table 1, Figs. 3 and 4). 



Results 



Development of Odontopyxis trispinoa 



Morphology Larvae of O. trispinosa are elongate and 

 slender with mean body depth at the pectoral fin ori- 

 gin of 11.7% SL in preflexion specimens decreasing to 

 10.7% SL in flexion and postflexion larvae (Tables 2 

 and 3). Mean head length is 18.4% SL in preflexion 

 larvae and increases to 23.8%< SL in juveniles (Table 

 3). Mean head width is approximately 50.0% HL 

 throughout larval development and decreases to 37.1% 

 HL in juveniles (Table 3). Mean snout length increases 

 from 20.4% HL in preflexion larvae to 27.0% HL in 

 postflexion larvae and eye diameter decreases from 

 33.3% HL in preflexion larvae to 23.3% HL in juve- 

 niles. Mean pectoral-fin length increases from 7.0% SL 

 in preflexion larvae to 19.5% SL in postflexion larvae 

 (Table 3). The gut is moderately long: mean snout to 

 anus distance is 47.9% SL in preflexion larvae and 

 decreases to 33.0% SL in juveniles. 



Pigmentation Pigmentation in O. trispinosa larvae 

 was relatively consistent among specimens and is a 

 useful distinguishing character (Fig. 5). 



Head region Pigmentation on the head of preflexion 

 larvae is present as rows of melanophores on the up- 

 per and lower jaws. A few additional melanophores 

 are present on the snout. Melanophores on the opercu- 

 lar and hyoid regions join the upper and lower jaw 

 pigmentation to form a continuous swath giving lar- 

 vae a "bearded" appearance (Fig. 5A). In flexion lar- 

 vae, additional melanophores appear posterior to the 

 eye. 



Lateral body and gut region The dorsolateral sur- 

 face of the body above the gut is covered with melano- 

 phores with the exception of a patch along the dorsal 

 midline above the pectoral fin. The dorsolateral pig- 

 mentation recedes ventrolaterally toward the gut with 

 development and is completely absent in postflexion 

 larvae. Melanophores cover nearly the entire caudal 

 portion of the body in preflexion larvae. In some speci- 

 mens, the notochord tip is unpigmented. In late flexion 

 and postflexion larvae, pigmentation on the lateral body 

 surface begins to separate gradually into seven bands 

 (Fig. 5D). The first band extends from the posterior 

 region of the first dorsal fin to the ventral body mid- 

 line immediately posterior to the anus. The second 

 band extends between the first two soft rays of the 



