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Fishery Bulletin 119(2-3) 
Figure 7 
Illustrations of 3 early developmental stages of larval Lampanyctus sp. D caught in the 
central South Pacific Ocean in 1985 at station 3052: (A) 7.8 mm standard body length 
(SL), (B) 9.5 mm SL, and (C) 12.9 mm SL. 
located dorsally in the intestine terminus and anterior at 
the liver, one unpaired melanophore anterior to the fore- 
brain, paired melanophores between the forebrain and mid- 
brain, one melanophore posterior to the midbrain, and one 
melanophore posterior to the hindbrain (Fig. 6). In addition, 
most larvae have 1 or 2 melanophores on the cleithrum at 
the level of the pectoral fin. In about half of all studied spec- 
imens, a single melanophore is visible on the inner side of 
the operculum at the level of the pectoral fin, and internal 
pigmentation occurs at the myosepta of the epaxial and 
hypaxial myomers in the middle part of the tail at the level 
of the adipose fin (Fig. 7). Less than a third of the larvae 
have melanophores on the tip of the lower jaw. Sometimes 
melanophores are present above the brain: 1 or 2 unpaired 
in the middle of the midbrain, on both sides or only on one 
side anterior to the hindbrain. The peritoneum is pigmented 
with large melanophores in all larvae; in some larvae, this 
pigment appears on the myosepta above the gut. 
Photophore formation Br, are noticeable on the 9.5-mm-SL 
larva. 
Comparative remarks Among the species inhabiting 
the study area, L. macdonaldi, L. gibbsi, and L. wisneri 
are the only species for which larvae are unknown. The 
meristic characters of the adults of these 3 species differ 
from the meristic features indicated for the larvae of Lam- 
panyctus sp. D described here. Lampanyctus sp. D is 1 of 4 
more species of Lampanyctus that McGinnis (1982) noted 
occur in the central South Pacific Ocean, with the other 
species being Lampanyctus sp. A, Lampanyctus sp. B, and 
Lampanyctus sp. C. Lampanyctus sp. C and Lampanyc- 
tus sp. D are characterized by a lower number of fin rays 
compared with the number for Lampanyctus sp. A and 
Lampanyctus sp. B (P: 14-15, D: 12-18, A: 16-18 versus 
P: 17, D: 14-16, A: 16-21) (Table 2). Meristic characters 
of Lampanyctus sp. C and Lampanyctus sp. D are similar 
to those described for the larvae examined in our study. 
Adults of these 2 species differ from each other in the rela- 
tive position of unpaired fins and in the morphology of the 
supracaudal luminous gland; therefore, we will not be able 
to use these features to identify larvae examined in our 
study. However, McGinnis (1982) suggested that juveniles 
of Lampanyctus sp. C less than 30 mm SL are character- 
ized by the presence of a large vertical band of pigment 
posterior to the pectoral fin. Among all the species of the 
southwestern Pacific Ocean whose larval development is 
already known, L. australis is the only species whose lar- 
vae have such pigmentation. Our larvae do not have such 
pigmentation at least up to a size of 17 mm SL; therefore, 
