FISHERY BULLETIN: VOL. 81, NO. 2 



Ep U*] 



FIGURE 8.— Development of the caudal fin osteology in larvalA/osa sapidissima. Fin rays are omitted to clearly show support osteology: 

 (A) Farly preflexion, 9.2 mm; (B) late preflexion, 10.8 mm; (C) flexion, 13.2 mm; (D) late flexion, 16.9 mm. Hy (1-6) = hypural plates; Ep 

 = epurals; U(l-2) = ural vertebra; Pu(l-2) = preural vertebra; Hs = haemal spine; Nc = notochord; Ur(l-2) = uroneurals; Ns = 

 neural spine; Ph= parhypural; Na = neural arch. Clear areas indicate uptake of Alizarin Red S (except for Nc in A, B.andC), while 

 stippled areas indicate uptake of Alcian Blue. 



There appears to be a distinct cartilaginous fusion 

 between the haemal spine and the parhypural bones 

 (Fig. 8D). 



Postflexion larval and juvenile A. sapidissima show 

 complete separation between the ural and preural 

 vertebrae (Fig. 9). The hypurals, neural and haemal 

 spines, neural arch, and the epurals all absorbed 

 Alizarin Red S and Alcian Blue stains. The epurals no 

 longer were fused. The third uroneural was stained 



with Alcian Blue. These structures do not appear to 

 completely ossify until well into the juvenile stage of 

 development. A field-sampled specimen 48.0 mm SL 

 showed complete Alizarin Red S absorption in the 

 hypurals, ural and preural vertebrae, and the neural 

 arch. The neural and haemal spines and parhypural 

 exhibited proximal end absorption of Alcian Blue to 

 preural vertebrae 1-4. The two epural bones had ab- 

 sorbed Alcian Blue at both the anterior and posterior 



332 



