36 



Fishery Bulletin 92(1), 1994 



melanophores in early larvae. 

 By early flexion, only one or 

 two postanal melanophores 

 were present along the ventral 

 midline and these were located 

 on the caudal peduncle and at 

 the posterior margin of the 

 hypural bones (Fig. 1). Pigment 

 was also present on the devel- 

 oping pelvic fins by early flex- 

 ion. Melanophores were distrib- 

 uted over the dorsal and anal 

 spines by 6.0 mm and over the 

 anterior-most dorsal and anal 

 rays by 8.5-9.5 mm. Pigment 

 covered all but the distal tips of 

 the dorsal and anal rays by 

 15.0 mm. Only the base of the 

 caudal- and pectoral-fin rays 

 were pigmented by 13.0-14.0 

 mm (Fig. 1) and pigment cov- 

 ered about 50% of the caudal 

 fin in a 23.0-mm larva. Pigment 

 occurred only over the proximal 

 portion of the dorsal-most pec- 

 toral-fin rays in the 23.0-mm 

 larva. 



Head spination and fin 

 development 



Tripletail larvae were charac- 

 terized by a vaulted, median 

 supraoccipital crest, which 

 originated above mid-eye, and 

 by numerous spines and ridges 

 on the head. Larvae of 2.2-2.4 

 mm had five to six spines along 

 the leading edge of the supra- 

 occipital crest and one spine on 

 the posterior edge (Fig. 1). Usu- 

 ally eight spines occurred along 

 the leading edge of the crest by 

 4.0 mm, giving the crest a ser- 

 rate appearance. Length of the 

 crest and its spines decreased 

 as larvae grew (Fig. 1); and the 

 entire supraoccipital crest was 

 resorbed by 15.0-16.0 mm. The 

 surface of the supraoccipital 

 and frontal bones had a reticu- 

 lated pattern of depressions or "waffled" appearance 

 (Fig. 2). Because so few preflexion larvae were col- 

 lected, we were unable to determine when this char- 

 acter first appeared. A large, laterally projecting 



Figure 1 



Larval development of tripletail iLobotes surinamensis) from the north- 

 ern Gulf of Mexico. (A) 2.2 mm, (B) 4.0 mm, (C) 6.3 mm, (D) 8.5 mm, (E) 

 10.8 mm, (F) 13.7 mm. All measurements are standard length (SL). 



supraorbital ridge with a single spine was present 

 above the eye of tripletail larvae by 4.0 mm. Both 

 the supraorbital spine and ridge were resorbed by 

 19.0 mm. Single, simple spines were present on the 



