I OLLINS ET AL : LARVAL AND JUVENILE RED SNAPPER 



eral lack of development has also been observed in 

 laboratory-reared larvae of L. campechanus <4.0 

 mm (Rabalais'*). 



Pigmentation 



Diagnostic melanophores occurred on various 

 regions of the specimens (Table 2). The first 

 melanophore to appear on the head was on the 

 dorsal midline over the midbrain. The dorsal sur- 

 face of the peritoneum was nearly covered by large 

 melanophores in all specimens. The presence and 

 amount of pelvic fin pigment was variable. Fading 

 of the pigment in some specimens was probably 

 due to the preservation and/or handling. When 

 pelvic fin pigment was present in specimens <7.3 

 mm, it was located only on the fin membrane. Our 

 undamaged specimens s=7.3 mm had pelvic fin 

 melanophores primarily on the most anterior soft 

 ray (Figure ID) and/or in the fin membrane (Fig- 

 ure 2B). 



The largest juvenile had the most pigmentation 

 (Figure 2C). Four vertical bars made up of small 

 melanophores were located between the head and 

 the caudal section. All fin membranes between the 



*N. Rabalais, University of Texas Marine Laboratory, Port 

 Aransas, TX 78373, pers. commun. October 1978. 



2d and 10th posteriormost spinous dorsal rays had 

 three melanophores between each spionous ray. 

 The soft dorsal fin had five melanophores on the fin 

 membranes between the 7th and 13th pos- 

 teriormost rays. An additional melanophore was 

 present near the distal end of the dorsal principal 

 caudal rays. Unfortunately, specimens were not 

 available to link the development of pigmentation 

 between 12.4 and 22.4. 



Fin Formation 



Dorsal and pelvic fins were the first to begin 

 development in L. campechanus (Figure lA), fol- 

 lowed by caudal, anal, and pectoral fins. The adult 

 complement of fin spines and rays was completed 

 in the following order: caudal (principal rays 

 only), pelvic, pectoral, dorsal, and anal (Table 3). 



Dorsal Fin 



The smallest illustrated specimen had de- 

 veloped only the five anteriormost dorsal spinous 

 rays (Figure lA). Most dorsal soft rays seemed to 

 develop simultaneously, with the exception of the 

 posteriormost soft rays which developed last. The 

 total adult number of dorsal fin rays ( 24 ) was pres- 

 ent at 4.9 mm, with the 2 posteriormost dorsal 



Table 2. — Number of melanophores on regions of larval andjuvenileLutjanus campechanus. When available, several larvae of a given 



size were used in determining the number of melanophores. 



'Specimen was damaged and no count was taken 

 ^Juvenile 



967 



