Feeney: Post-yolksac development of two southern California sculpins 



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Spination Preopercular spines begin to develop in the 

 late preflexion stage at ~5.5mm NL; the 5.6 mm spe- 

 cimen (in Fig. 2B) has developed 2 spines. During flex- 

 ion, the number of preopercular spines increases to 5 

 (Table 2, Fig. 2C). 



In postflexion larvae, the preopercular spines number 

 6-12 (Table 2); the upper spine is elongated. A post-tem- 

 poral/supracleithral spine appears at 8 mm (Fig. 2D). 



By 9.7 mm, a pair of nasal spines appear (Fig. 3A). 

 The dorsalmost preopercular spine elongates to about 

 twice the length of other spines. The number of post- 

 temporal/supracleithral spines increases to 3. At 9.8 

 mm, a small spine (not illustrated) may be present 

 where the sensory canal forms over the parietal, 

 anterior to the nape; the spine persists in specimens 

 up to 11mm SL (CAS SU 68789). 



In juveniles, multiple preopercle spines (about 10) 

 coalesce to 1 elongate, bifurcated uppermost spine and 

 2 convex undulations ventrally where the other spines 

 had been. Larval post-temporal spines form the anter- 

 iormost part of the lateral line which later becomes 

 decorated with a series of multispined scales. Smaller 

 spines (prickles) form laterally below the 2d dorsal and 

 lateral line. 



Pigmentation In yolksac Clinocottus analis, about 

 140 dense melanophores in 6-7 rows line the dorso- 

 posterior gut (peritoneal) membrane (Eigenmann 1892, 

 Budd 1940). Nape melanophores number 11-15 with 

 several extending onto a bubble of skin that is usually 

 present at the anterior nape. A stellate melanophore 

 can usually be found on the head over one or both sides 

 of the midbrain. A row of 18-25 PAVM is present from 

 about the 6th postanal myomere to the caudal area; the 

 last 2-3 melanophores usually extend down into the 

 finfold. 



Post-yolksac larvae retain much of the appearance 

 of the yolksac larvae (Fig. 2A). The number of PAVM 

 may increase to 33, but usually ranges in the mid-20s, 

 generally decreasing in larger larvae (Fig. 4). 



Late preflexion larvae develop numerous head 

 melanophores over the midbrain (Fig. 2B). One 4.6 mm 

 specimen had 19 midbrain melanophores and one 

 forebrain melanophore; however, the melanophores 

 over the midbrain usually number 10-15 with no fore- 

 brain pigment. Melanophores sometimes form at the 

 anus in this stage; however, these usually form in the 

 postflexion stage. One 5.2mm specimen had 5-6 

 melanophores in a circle around the anus. 



By 9.7mm, the number of PAVM has decreased to 

 less than 23 (Fig. 4). In a 9.8mm specimen (Fig. 3B), 

 melanophores begin to form below the nape and lateral- 

 ly below the second dorsal fin. 



