A second type of Sebastes larva is represented by the 

 subspecies S. p. pachycephalus and S. p. nigricans. Lar- 

 vae of the two subspecies are extruded at lengths of 5.5 to 

 6.4 mm and 6.2 to 6.3 mm notochordal length, respec- 

 tively, slightly larger than in eastern Pacific species. 

 They also develop a striking pattern of melanophores. 

 The first pigment to appear in embryos is a patch over 

 the dorsal surface of the gut and a patch directly above 

 this over the trunk. With further embryonic develop- 

 ment, a large patch forms on the dorsal surface of the 

 head and the base and blade of the pectoral fin is covered 

 solidly with melanophores. As in the S. oblongus group, 

 larvae of S. pachycephalus do not develop the series of 

 ventral midline melanophores that is present in eastern 

 Pacific and Atlantic Sebastes. At hatching, the heavy 

 trunk band is augmented and melanophores have spread 

 to the lateral and ventral surfaces of the gut. With fur- 

 ther development, melanophores are added to the oper- 

 cular region and the pectorals become solidly black. 



The two subspecies differ in the pigmentation of the 

 trunk and tail. Larvae of S. p. pachycephalus augment 

 the anterior trunk band throughout larval development 

 but develop no pigmentation on the posterior trunk and 

 tail (Fig. 22D). Late in the larval period, two wide bands 

 develop on the tail, one below the soft dorsal fin and one 

 at the caudal peduncle. In preflexion larvae of S. p. nig- 

 ricans, a line of melanophores extends posteriorly from 

 the heavy trunk band to the caudal region (Fig. 221). In 

 later larval stages, melanophores are added to the lateral 

 trunk and tail to form a continuous mass of pigment 

 along the lateral body surface. The pelvic fins are solidly 

 pigmented in both subspecies. 



A third type of pigment pattern in Japanese Sebastes 

 larvae is similar to that found in some species of the 

 eastern Pacific and Atlantic. Late intraovarian larvae of 

 S. steindachneri (Fig. 22E), S. taczanowskii (Fig. 22F), 

 and S. schlegeli (Fig. 22G) all have a row of 

 melanophores on the ventral midline of the tail, an op- 

 posing row along the dorsal midline, a patch on the dor- 

 sal surface of the brain, and a solid shield over the gut. 

 They differ in the number of melanophores in each of the 

 rows. Mean values for the number in the vental row of S. 

 steindachneri, S. taczanowskii, and S. schlegeli are 16.3, 

 9.9, and 9.5, respectively, and for the dorsal row 18.7, 9.3, 

 and 10.3, respectively. Size ranges in notochordal length 

 for full-term larvae of the three species are 3.4 to 4.6 mm, 

 4.2 to 5.2 mm, and 4.8 to 6.8 mm, respectively. 



A fourth species that falls into this group is S. iner- 

 mis. Larvae are born at about 4 to 5 mm in length and 

 Harada (1962) shows only dorsal head and gut pigment 

 at this stage. His illustrations of 6- to 10-mm larvae show 

 a short row of ventral and dorsal midline melanophores, 

 but no numbers are given (Fig. 22H). No pectoral fin pig- 

 ment is present on this species nor on the preceding 

 three. 



Helicolenua Goode and Bean 



Literature. — Larvae of Helicolenus dactylopterus 

 have been described and illustrated by a number of 



workers. Fage (1918) described a series of larvae 5.5 to 14 

 mm long from the Mediterranean Sea and illustrated the 

 largest and smallest individuals of the series. Sparta 

 (1942, 1956) described more completely the larval and 

 early juvenile stages of H. dactylopterus from the 

 Mediterranean and illustrated numerous larval stages 

 and some juveniles. Haigh (1972) described the os- 

 teological development of a larval series from off South 

 Africa. A series of excellent illustrations of H. dactylop- 

 terus are included with Taning's (1961) description of 

 redfish larvae from the North Atlantic. 



Distinguishing features.— Larvae of Helicolenus can 

 be differentiated from those of other scorpaenid genera 

 by a combination of characters. Like Sebastes, larvae of 

 H. dactylopterus have a small pectoral fin base (Table 

 3). Depth of the fin base averages 11% of the body length 

 in larvae before notochord flexion, 12.5% during flexion, 

 and 12% after flexion is completed. The range for the en- 

 tire larval period is 9 to 14%. The blade of the fin is short 

 and rounded. Fin length averages 11% of the body length 

 in preflexion larvae, 15% during flexion, and 18% fol- 

 lowing flexion. Another distinctive feature is the mass of 

 spongy tissue which forms at the dorsal midline of the 

 trunk. It appears within the dorsal finfold in 4-mm 

 larvae in the region to be occupied by the spinous 

 dorsal fin. In later stages the spinous dorsal rays form 

 within the mass and erupt from it. Such tissue has 

 not been described for larvae of any other scorpaenid 

 genus. 



Larvae of the species of Helicolenus from the eastern 

 Pacific off Chile, H. lengerichi, were not available for 

 study. For comparative purposes, a brief description of a 

 series of the North Atlantic species, H. dactylopterus, is 

 given below and accompanied by the illustrations of Poul 

 Winther (Taning 1961). 



Helicolenus dactylopterus (Delaroche), Figure 23 

 Literature. — See above. 



Distinguishing features. — Planktonic eggs of H. dac- 

 tylopterus have not been described, and there is uncer- 

 tainty about the mode of reproduction of this species. 

 Krefft (1961) reported that ovaries of reproductively 

 mature females contained developing embryos em- 

 bedded in a gelatinous matrix. Thus, Helicolenus may be 

 ovoviviparous as in the subfamily Sebastinae or may pro- 

 duce a gelatinous egg balloon as in many genera of the 

 Scorpaeninae. Krefft (pers. commun.) has suggested 

 that the ovoviviparity may be facultative. Larvae are 

 small at hatching as in the Scorpaeninae; Sparta (1942) 

 illustrated a 2.8-mm larva that has already utilized its 

 yolk and is morphologically similar to Scorpaena larvae 

 of that size. 



Body depth is moderate and increases throughout the 

 larval period, from an average of 29% of the body length 

 in preflexion larvae, to 33% in larvae undergoing flexion, 

 to 37% in postflexion larvae (Table 25). The gut is com- 

 pact. Snout-anus distance averages 49% of the body 



38 



