REDESCRIPTION OF LARVAE OF THE PIGFISH, ORTHOPRISTIS 

 CHRYSOPTERA LINNAEUS (PISCES, HAEMULIDAE) 



William Watson 1 



ABSTRACT 



A size series of larval pigfish, Orthopristic chrysoptera, was assembled from specimens collected from the 

 lower Cape Fear River Estuary, North Carolina, and from the gulf coast of Texas. Larvae are rather heavily 

 pigmented, principally along the ventral midline. Specimens up to about 9 mm SL have 13 to 19 ventral 

 melanophores along the tail with those between the 19th and 22d myomeres typically larger. A dorsal 

 melanophore usually is present above the largest ventral melanophore. At about 9 mm SL midlateral 

 pigmentation begins near the peduncle and internal pigment appears posteriorly above and below the 

 vertrbral column. By about 15 mm SL a distinct pattern of dorsal, lateral, and ventral longitudinal stripes is 

 present. Pigfish larvae may be separated from similar cooccurring species by various combinations of pig- 

 ment pattern, very small preopercular spines, and myomere and fin ray counts. 



Larval development of the pigfish, Orthopristis chry- 

 soptera, was described by Hildebrand and Cable 

 l L930) based on reared yolk-sac stage larvae and older 

 field specimens collected near Beaufort, N.C. They 

 described yolk-sac stage larvae as having a barred 

 pattern, with dorsal and ventral melanophores on the 

 trunk at the level of the anus and at midtail, but 

 stated that preserved larvae between about 3 and 15 

 mm were unpigmented. Scotton et al. (1973) illus- 

 trated a 12.3 mm larva with series of melanophores 

 along the ventral and lateral midlines of the tail, and a 

 few dorsally on the head. Johnson (1978) sum- 

 marized these earlier descriptions, but added no 

 new information. 



Pigfish larvae collected from the lower Cape Fear 

 Riser Estuary, N.C, differed from Hildebrand and 

 Cable's (1930) description in that they maintained 

 the barred pattern well past the yolk-sac stage, and 

 had considerable pigment along the ventral midlines 

 of the gut and tail throughout the larval period. 

 Pigfish larvae from the northern Gulf of Mexico were 

 examined subsequently and found to be pigmented 

 in these same areas. 



Since larval pigment of pigfish is heavier and more 

 persistent than previously described, larval develop- 

 ment (emphasizing pigment) is redescribed here, 

 based principally on specimens from the Cape Fear 

 River Estuary. Specimens larger than 9.2 mm are 

 from the northern Gulf of Mexico, since larvae of this 

 size were not taken in the Cape Fear River 

 Estuary. 



MATERIALS AND METHODS 



Larvae were collected from the lower Cape Fear 

 River Estuary in May and June 1977 with 0.5 mm 

 mesh nets of approximately 0.6 m : mouth area, towed 

 at ca. 0.5 m/s (Copeland et al 1979 : ). Samples were 

 fixed immediately in the field in unbuffered 5-10', 

 Formalin,' and the pigfish larvae subsequently 

 removed were stored in 2.5' < seawater-Formalin. 



Larvae were examined under a dissecting micro- 

 scope equipped with an ocular micrometer. Counts 

 and measurements (made to the nearest 0.04 mm 

 and reported to the nearest 0.1 mm) were made on 

 the left side. The following dimensions were record- 

 ed: Total length, standard length, head length, snout 

 length, eye diameter, preanal length, and depth at 

 pectoral fin insertion. These measurements are 

 defined by Saksena and Richards (1975). Lengths 

 given in the text refer to standard length unless other- 

 wise specified. Drawings were made with the aid of a 

 camera lucida. All specimens were lightly stained 

 with alizarin to aid in drawing and in counting fin rays 

 and preopercular spines. Two larvae (11.8 and 13.2 

 mm) were cleared and stained following the method 

 of Hollister (1934). 



Descriptions are based on 19 Cape Fear and 4 Gulf 

 of Mexico specimens; 26 additional postflexion Gulf 

 of Mexico specimens were briefly examined for 



'Marine Ecological Consultants of Southern California, 531 

 Encinitas Blvd., Suite 110, Encinitas, CA 92024. 



; Copeland, B. J., R. G. Hodson, and R.J. Monroe, 1979. Larvae and 

 postlarvae in the Cape Fear Estuary, N. C, during operation of the 

 Brunswick Steam Electric Plant 1974-1978. Report 79-3 to Car- 

 olina Power and Light Co., Raleigh, N.C. 



'Reference to trade names does not imply endorsement by the 

 National Marine Fisheries Si ice, NOAA. 



Manuscript accepted Februarv 198:( 

 FISHERY BULLETIN: VOL. si. NO -i. L983 



847 



