FISHERY BULLETIN: VOL. 82. NO. 1 



juveniles of gulf menhaden spawned and reared in 

 the laboratory using morphometries, meristics, and 

 pigmentation features, and I compare gulf menhaden 

 larvae with yellowfin menhaden larvae described by 

 Houde and Swanson (1975). Morphometric and 

 meristic data on laboratory-spawned and reared 

 Atlantic menhaden are also presented to supplement 

 the composite description of this species by -Jones et 

 al. (1978) and to aid in the separation of Atlantic 

 menhaden and yellowfin menhaden larvae. Charac- 

 ters for separating Brevoortia from other clupeids are 

 reviewed. 



cleithra, exclusive of the finfold. 

 Dorsal and anal fin base lengths — distance from 



anterior to posterior edges of fin base; in larvae with 



incomplete fins, distance from origin of first ray to 



the insertion of the last ray. 

 Head length— tip of snout to posterior margin of otic 



capsules in yolk-sac larvae; tip of snout to opercular 



margin in older larvae and juveniles. 

 Snout length — tip of snout to anterior margin of 



eye. 

 Eye diameter — horizontal distance between anterior 



and posterior edges of fleshy orbit. 



METHODS 



Gulf menhaden were collected as mature adults in 

 September 1981 near Gulf Breeze, Fla., tranported 

 to the Beaufort Laboratory, and induced to spawn 

 with human chorionic gonadotropin (HCG) and carp 

 pituitary (Hettler 1983). Spawnings that occurred in 

 November 1981 and February 1982 provided a 

 developmental series of eggs, larvae, and juveniles 

 up to 90 d old, reared at a temperature of 20° ± 2°C 

 and a salinity of 30%o. One hundred eggs, preserved 

 during the early embryo stage, and 100 live eggs 

 were measured. 



Atlantic menhaden were captured as juveniles in 

 September 1978 near Beaufort, N.C., and reared to 

 sexual maturity in the laboratory for 19 mo. They 

 were induced to spawn in April 1980, and the larvae 

 were reared at temperatures that began at 15°C and 

 increased to 25°C during development (Hettler 

 1981). This spawning resulted in a developmental 

 series of larvae and juveniles up to 130 d old. 



All specimens were preserved in 2% buffered for- 

 maldehyde in seawater before being measured. The 

 following morphometic measurements were taken 

 with an ocular micrometer in a dissecting microscope 

 on 123 gulf menhaden and 196 Atlantic menha- 

 den. 



Standard length (SL) — tip of snout to tip of 

 notochord before and during notchord flexion; in 

 postflexion larvae, tip of snout to posterior margin 

 of hypural bones. All references to length in this 

 paper are standard length unless otherwise 

 stated. 



Preanus length — tip of snout to posterior end of 

 anus, measured along midline. 



Predorsal length — tip of snout to anterior edge of 

 dorsal fin base, measured along midline. 



Prepelvic length — tip of snout to anterior insertion of 

 pelvic fin, measured along midline. 



Body depth — vertical depth at symphysis of the 



Myomeres were counted on semidry specimens (not 

 completely immersed) up to 1 7 mm with transmitted 

 unpolarized light by adjusting the microscope mirror 

 to give maximum contrast between myosepta and 

 myomeres. Myomeres were classified as follows: 



Total myomeres — all myomeres between the most 

 anterior myoseptum and the most posterior 

 myoseptum. 



Preanal myomeres — number anterior to the myo- 

 mere in which the anterior ray of the anal fin is 

 inserted or to the myomere in contact with the 

 downward curve of the dorsal margin of the anus in 

 larvae without anal fin rays. 



Postanal myomeres — number posterior to the 

 anterior insertion of the anal fin. 



Predorsal myomeres — number anterior to the 

 myomere containing the origin of the first dorsal 

 fin ray. 



Postdorsal-preanal myomeres — number between 

 the myomere connected to the last dorsal fin ray and 

 the most posterior preanal myomere. 



Following morphometric measurements on all 

 specimens and myomere counts on specimens with 

 visible myomeres, the pigment pattern was recorded 

 and specimens of gulf menhaden were illustrated 

 with a camera lucida. Atlantic menhaden were not 

 illustrated as the figures in Jones et al. (1978) are 

 adequate. 



Specimens were then used for counts of fin rays, 

 pterygiophores, predorsal bones, vertebrae, and 

 scutes. Specimens were transferred to 95 /f ethanol, 

 stained with alcian blue for cartilage, cleared with 

 trypsin, stained with alizarin red S for bone, and 

 stored in 100% glycerin 4 . 



"Taylor, W. R., and G. C. Van Dyke. 1978. Staining and clearing 

 small vertebrates for hone and cartilage study. Unpubl. manuscr., 

 19 p. National Museum of Natural History, Washington, DC 

 20560. 



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