WATSON: REDESCRIPTION OF PIGFISH LARVAE 



end of the larval period (Fig. 2d). Myoseptal 

 melanophores develop late in the larval stage, par- 

 ticularly on the lower half of the body between about 

 the level of midgut and the peduncle. 



The gut and isthmus are moderately pigmented 

 along their ventral midlines through notochord flex- 

 ion: 6 to 1 1 melanophores are arrayed between the 

 cleithral symphysis and the anus (Fig. 3). This num- 

 ber decreases in postflexion larvae, but at least one 

 melanophore remains between the pelvic fin bases 

 together with two or three between the pelvic bases 

 and anus. One or two midline melanophores precede 

 the cleithral symphysis throughout larval de- 

 velopment. 



Dorsal visceral pigment through most of the larval 

 period consists of a single large melanophore over the 

 hindgut where it turns down at the 9th or 10th 

 myomere, and several melanophores over the pos- 

 terior dorsal surface of the swim bladder. Occasional- 

 ly a second melanophore lies over the hindgut 

 between these areas. Swim bladder pigment extends 

 forward to cover the entire dorsal surface during late 

 postflexion. At this same time pigment proliferates 

 over the hindgut and anterior to the swim bladder to 

 form a band continuous with the vertebral pigment. 



Pigfish larvae retain a melanophore at the angle of 



the lower jaw throughout the larval period. A 

 melanophore may sometimes occur under the 

 hindbrain before notochord flexion but this typically 

 is absent until after notochord flexion. Pigment pro- 

 liferates rapidly under the hindbrain in postflexion lar- 

 vae, forming a continuous line with the vertebral and 

 dorsal gut pigment. Pigment develops on the roof of 

 the mouth during late postflexion, completing an in- 

 ternal stripe extending the length of the body. Near 

 the end of the larval period pigment develops around 

 the posterior midbrain and anterior hindbrain. Pig- 

 ment may appear along the upper lip at ca. 9 mm, but 

 is not consistently present until ca. 11 mm. Pigment 

 develops along the lower lip at ca. 11 mm. External 

 melanophores appear at the nostril and behind the 

 eye at the end of the larval period, completing a near- 

 ly continuous external midlateral stripe extending 

 along the entire length of the fish (Fig. 2d). 



Dorsal head pigment first develops above the mid- 

 brain in postflexion larvae (Fig. 2b) at ca. 1 1 mm. This 

 pigment proliferates rapidly to form longitudinal 

 head stripes which become continuous with the dor- 

 sal trunk stripes by the end of the larval period (Fig. 

 2d). Pigfish larvae at this stage, although more heavi- 

 ly pigmented, display nearly the same pattern de- 

 scribed by Hildebrand and Cable (1930). 



*w~ -— --- ^Jk^*h - 



11.1 mm. Specimens "a" through "e" are from North Carolina; specimen "f" is from the gull coast of Texas. 



851 



