FISHERY BULLETIN: VOL 86, NO 1 



Table 2.— Meristic counts from cleared and stained larval and juvenile Macruronus novaezelandiae Specimens between dashed lines are 



undergoing notochord flexion, a = specimen damaged; b juveniles not stained. 



Length 

 (mm) 



37 



3.9 



4.2 



4.6 



4.8 



5.2 



6.0 



74 



9.4 



9.9 



11.5 



16.3 



17.4 



19.8 



dorsal 



4 + 28 



+ 19 



9 + 74 



12 + 84 



12 + 86 



13 + 87 



Fin rays 



anal pectoral pelvic 



Branchi- 



ostegal 



rays 



Gill rakers 



upper lower total 



Total 

 centra 



Neural 

 spines 



Haemal 

 spines 



18 

 4 

 60 

 73 

 76 

 86 



4 

 8 

 8 



8 



1 

 1 

 3 

 3 

 5 

 6 

 6 

 7 

 7 

 7 

 7 



8 

 6 



12 

 15 

 15 

 15 



8 

 6 

 12 

 16 

 18 

 20 



5 

 42 

 38 

 55 

 70 

 71 

 73 



1 



1 



2 



2 



2 



3 



6 



55 



54 



58 



70 



70 



74 



37 

 34 

 42 

 55 

 55 

 57 



Caudal 

 elements 



3 

 3 



4 



may start as early as 9.4 mm with the full comple- 

 ment (8 rays) present by 16.3 mm. Ossification 

 proceeds from the outer to the innermost rays. 



The second dorsal fin anlage is visible in larvae 

 of 5.7 mm. Bases are first visible by 6.9 mm, with 

 ray ossification commencing by 7.3 mm. Al- 

 though the anal fin anlage does not form until 6.9 

 mm, complete ossification is reached before that 

 of the second dorsal. Distinct anal fin bases are 

 first visible in 7.2 mm larvae and ossification has 

 consistently begun by 9.9 mm. The full comple- 

 ment of anal rays is present by 21.0 mm and for 

 the second dorsal, by 23.2 mm. 



The first dorsal starts development slightly 

 later than the second dorsal, although it is the 

 first fin to complete ossification. The full comple- 

 ment of 12 or 13 elements is present by 16.3 mm. 



Pectoral buds were first observed in larvae 4.5 

 days posthatch (3.2 mm). However, the pectoral 

 fin is the last to complete development. Ossifica- 

 tion of pectoral rays starts by 16.3 mm; a 34.2 mm 

 specimen had only 15 ossified rays, still short of 

 the 20 rays of juveniles. Sequence of ossification 

 is from upper to lower. 



The caudal fin anlage first appears on the ven- 

 tral surface of the notochord just anterior to the 

 tip in larvae of 10.4 mm. Flexion begins at 20 mm 

 and is usually complete by 28 mm. Ossification of 

 all caudal elements was incomplete in a 34.2 mm 

 specimen. Insufficient material of the appropriate 

 size was available to define the completion of cau- 

 dal ossification. 



The caudal complex in M. novaezelandiae is 

 based on two ural centra, two epurals, a superior 

 hypural (HP3 + 4), inferior hypural (HPl + 2), 

 and a parhypural (Fig. 3). Eight to nine rays ar- 

 ticulate with these elements — one or two rays on 

 the second epural, three rays on the superior hy- 

 pural, two on the inferior hypural, and one ray 

 each on the first epural and the parhypural. Sin- 

 gle rays also articulate with the elongate neural 

 and haemal spines of the first preural centrum. X 

 and Y bones are present although they are not 

 readily distinguishable from dorsal and anal 

 pterygiophores. Total caudal fin ray counts are 

 low (12 or 13). 



Additional caudal structures occurred in one of 

 the six specimens examined. This specimen had a 

 twin haemal spine on the first preural centrum 

 and greatly elongated haemal spines on preural 

 centra 3-8 (1.3-1.4 times the length of corre- 

 sponding neural spines, Fig. 3). 



DISCUSSION 



The general morphology and pigmentation of 

 M. novaezelandiae larvae show broad similarities 

 to Merluccius and to gadine gadids. Characteris- 

 tic differences between M. novaezelandiae and 

 Merluccius species occur in fin structure and the 

 sequence of fin development. In Merluccius, the 

 caudal fin is the first to form, followed by the 

 pelvic. In Macruronus, caudal development is 

 late with the caudal fin being the second last to 



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