FISHERY BULLETIN; VOL. 87, NO, 4, 1989 



caudal fin remains unpigmented tiirougiiout 

 development. 



Development of Head Spines 



Larvae of G. marmoratus have complex and 

 well developed head spination (Fig. 3). Two 

 posterior preopercular spines (PPO2 and PPO3) 

 appear simultaneously at 4.6 mm (Fig. IB; see 

 Figure 3 for abbreviations also). Two more pos- 

 terior preopercular spines (PPOi and PPO4) de- 



velop by 5.7 mm and a fifth (PPO5) by 10 mm. 

 The PPOi spine becomes enlarged in juveniles, 

 reaching a relative length of ca. 12% BL (Fig. 

 3D). Two anterior preopercular spines (APO2 

 and APO3) form by 4.8 mm, followed by a third 

 anterior preopercular spine (APOj) by 5.4 mm. 

 All spines of both the anterior and posterior 

 preopercular margins merge by 6.8 mm and 

 only the APOi spine, the enlarged PPOi spine, 

 and the PP02_5 spines remain in juveniles (Fig. 

 3D). 



LPT 



APO, 



PST 



PPO, 



APO3 PPO3 



LIOi 



LIO, 



PPC 



PPO3 PPO2 



Figure 3. — Head spination in cleared and double-stained larval, transforming and juvenile Gymvapistes marmoratus. (A) 5.3 

 mm BL larva. (B) 6.8 mm BL larva. (C) 9.3 mm BL transforming larva. (D) 14.1 mm BL juvenile. Abbreviations: APOi, 

 1st anterior preopercular; APO2, 2nd anterior preopercular; APOa, 3rd anterior preopercular; lOP, infraopercular; LCL, lower 

 cleithral; LIOj, 1st lower infraorbital; LIO2, 2nd lower infraorbital; LOP, lower opercular; LPT, lower pterotic; NA, nasal; NU, 

 nuchal; PA, parietal; PPOi, 1st posterior preopercular; PPOo, 2nd posterior preopercular; PPOu, 3rd posterior preopercular; 

 PPO4, 4th posterior preopercular; PPO5, 5th posterior preopercular; PST, posttemporal; SCL, supracleithral; SO, supraocular; 

 UCL, upper cleithral; UIO,, 1st upper infraorbital; UIO2, 2nd upper infraorbital; UIO3, 3rd upper infraorbital; UIOj, 4th upper 

 infraorbital; UOP, upper opercular; UPT, upper pterotic. 



894 



