Ditty et al.: A redescription of Chaetodipterus faber larvae 



265 



anterior pale crossbar was situated above the middle 

 of the eye and the posterior crossbar was behind the 

 eye, extending mid-way down the preopercle. Lar- 

 vae <12.5 mm had only one band of pigment (Fig. 1). 

 The pelvics were the first fins to have pigment. 

 Pelvic fin buds were pigmented by 4.0 mm; the 

 pelvics were densely pigmented thereafter. Pigment 



Figure 1 



Larval development of Atlantic spadefish, Chaetodipterus faber, from the 

 northern Gulf of Mexico. (All. 8 mm; (Bl 3.5 mm; (C) 5.0 mm; (D) 7.0 mm; 

 (E) 11.6 mm. All measurements are standard length (SL). 



appeared on the pectoral fin along the proximal 

 portion of the rays at about 4.0-4.5 mm. Melano- 

 phores were lightly scattered over the pectoral fin 

 in the largest specimen examined (Fig. 1). Melano- 

 phores were scattered over the membrane covering 

 the anterior-most dorsal spines by about 6.0 mm and 

 the anal spines by about 8.0 mm. Melanophores 

 were added along the dorsal and 

 anal fins as larvae developed, cov- 

 ering the proximal-third of each 

 soft ray in the largest specimen 

 examined. Pigment was present 

 along the proximal portion of the 

 central rays of the caudal fin by 

 11.0 mm (Fig. 1). 



Head and body spination 



Atlantic spadefish larvae develop 

 two series of preopercular spines, 

 one along the posterior margin of 

 the outer shelf and the other 

 along the inner shelf. Both the 

 outer and inner shelf have dorsal 

 and ventral limbs. Three pre- 

 opercular spines were present 

 along the outer shelf of a 1.8-mm 

 larva, the largest of which was 

 present at its preopercular angle 

 (Fig. 1). A fourth and a fifth spine 

 were added by 3.5 mm, one dor- 

 sal and one ventral to the angle 

 of the preopercle. A sixth preop- 

 ercular spine, smaller than the 

 others and often difficult to locate, 

 was present by 5.0 mm. This sixth 

 spine was the anterior-most spine 

 along the ventral limb of the ex- 

 terior shelf and was resorbed by 

 11.0-12.0 mm in some specimens. 

 One larva we examined had seven 

 preopercular spines along the 

 outer shelf but most had two 

 spines along the dorsal limb, one 

 at the angle, and three along the 

 ventral limb (Fig. 2). Spines along 

 the outer shelf were simple. Two 

 to three spines were also present 

 along the inner shelf of the 

 preopercle by 3.5 mm. Number of 

 spines along the inner shelf in- 

 creased as larvae grew, resulting 

 in a serrate margin (Fig. 2). A 

 small, poorly developed opercle 



