Tolan and Newstead: Larval and |uvenile development of Brevoortia gunten 



729 



gunteri 

 patronus 



D 



gunten 

 patronus 



20 25 30 



Body length (mm) 

 Figure 3 (continued) 



base of the anal fin (Fig. 2). The predorsal midline 

 melanophores series was more prominent (51% of the 

 individuals displayed this pigment pattern). Additional 

 pigmentation included paired lateral melanophores near 

 the dorsal region of the brain cavity, internal pigment 

 above the notochord from the posterior margin of the 

 base of the dorsal fin to the caudal fin, and internal 

 pigment over the gas bladder. A large melanophore was 

 also present above the base of the pectoral fin. 



By 18 mm, the dorsal surface of the head became 

 highly pigmented with up to 25 small melanophores. 

 The snout, lower jaw, and pelvic fins were also pigment- 

 ed by this size. The dorsal and ventral surfaces of the 

 caudal peduncle, as well as the medial predorsal region 

 became more densely pigmented. Outstanding features 

 at this size included 2-9 ventrolateral melanophores in 

 a series along the digestive tract level with the pectoral 

 fins, and isthmus pigment was separated into two spots 



in many individuals. By 20 mm, the head region was 

 heavily pigmented and the mid-line predorsal pigment 

 progressed fully to the head. Ventrolaterally, 10-30 me- 

 lanophores forming a triangular pattern covered much 

 of the digestive tract. New pigmentation features at this 

 size included 1-3 small melanophores at the base of the 

 eye and an internal series below the notochord from the 

 base of the dorsal fin to the caudal fin. Pigmentation 

 at the pelvic fin insertion was lost in some specimens, 

 although it was still visible internally in all but one of 

 the cleared and stained specimens. Isthmus pigmenta- 

 tion was also lost at this size. 



Living juveniles (>20 mm) are silvery in color over 

 most of the body. The head, back, and dorsal and cau- 

 dal fins are all pigmented. In preservation, two dark, 

 slash-like pigments spots were present on the posterior 

 lateral body above and below the urostyle. In nearly 

 all other aspects, juvenile finescale menhaden closely 



