| At 3.2 mm SL, anus lies below about the 31st myomere, about 4/5 of the distance to caudal base. The jaws are oblique and the posterior tip of the maxilla extends somewhat past the anterior margin of eye, which is oval. The gill arches are naked, being free of both gill rakers and filaments. The intestine appears thick and obscurely convoluted. The upper median fin-fold originates at the nape, the lower one below the pectoral fin; the fin-fold at the tip of notochord seems to be differentiating. Only the base of dorsal fin is present; both the base of the anal fin and the air-bladder appear when the fish reaches about 4.0 mm SL.
Pigmentation: Elongated melanophores in row or spots are limited to the ventral surface, a characteristic condition of the larval stage, but they later show marked changes during subsequent growth stages. The melanophores along the median line of the isthmus seem to be separated into two or three spots in lateral view, but are continuous when viewed ventrally. Later, they extend anteriorly but disappear when the fish becomes an adult. Melanophores along the stomach diminish in number, disappearing when the fish reaches about 15.0 ml SL. On the mid-ventral line of the intestine can be found an obscure line of slender melanophores, which are destined to vanish at about 7 mm SL. A few spots above the posterior half of the intestine are faintly discernible, but the one near the anus is very distinct. One melanophore lies on the future anal fin base, two are on the lower edge of the caudal peduncle, and one is found on the lower lobe of the caudal fin.
At 6.3 mm SL, notochord is bent and the hypurals are developing. The air-bladder has broadened and lengthened. The dorsal, anal and caudal fin rays can be enumerated. Caudal fin still not forked. Median finfolds become less deep. The tip of the lower jaw remains terminal and pointed. The posterior tip of the maxilla has moved back to about in front of the center of the eye, which is still oval shaped. Minute denticulations, about 5 on the maxilla and 3 on the lower jaw, can be seen. The gill arches remain exposed. One to three gill rakers on the lower limb of first arch and gill filaments on the 2nd to 4th arch are present.
Pigmentation: A conspicuous black melanophore occurs on the midpoint of cleithrum, an expanded one occurs on the air-bladder and an oblique one on the upper hypural fan. The row of melanophores on the midventral line of the intestine is fading away and the two spots on the caudal peduncle have become continuous.
At 8.3 mm SL, Flap of opercle and nostrils are present. The anus has moved to 30th myomere. Twelve rays on both dorsal and anal fins are present. Caudal rays are present.
Pigmentation: A spotted melanophore on the anterior margin of the auditory vesicle and one on the lower part of the cleithrum have appeared, but the row along the midventral line of the intestine has disappeared. Melanophore rows on the stomach are either horizontally expanded or shrunken depending on the specimen.
At 10.7 mm SL, body form changes more pronounced at this stage. Cross striations along the body have disappeared. The posterior tip of the maxilla terminates below the center of the pupil. The pelvic fin bud is first seen below the 15th myomere at the junction of the stomach and the intestine which somewhat becomes permanent. Two or three dorsal rays lie vertically behind the anus. The tip of the snout becomes truncated in dorsal view.
Pigmentation: A black pigment has appeared on the upper tip of the notochord and on the lower hypural fan. The melanophore under the pectoral fin has disappeared and the row of melanophores along the stomach is also fading. One or two melanophores may be recognizable on upper part of the caudal peduncle in some specimens. The pigment on the anal base tends to split into spots.
At 14.1 mm SL, Tip of the snout becomes rounded, with the lower jaw still terminal. The body has slightly deepened. The posterior tip of maxilla reaches to below the posterior margin of eye. The anus has advanced to the 29th myomere. Dorsal and anal fin rays are well formed. About 4 pelvic fin rays can be counted.
Pigmentation: Additional melanophores occur on top of the auditory vesicle and under the opercle. A row of melanophores now reappears along the ventral line of the body dorsal to stomach, of which the most anterior one is very prominent.
At 18.4 mm SL, the tip of the snout has become more rounded, but the lower jaw still projects slightly beyond the upper, which now has 2 supra-maxillae. The posterior tip of the maxilla extends beyond the posterior margin of eye. Nostrils separated into pores. The opercle has expanded to cover the gill arches. In all of the foregoing stages, the alimentary tract is suspended by the dorsal mesentery. The anus has advanced to the 28th myomere and 2 or 3 vertical rays of the dorsal fin are still behind the anus. The pelvic fin rays number 7. A transparent alar flap appeared on the 6th principal rays from the top and bottom of the caudal fin.
Pigmentation: New melanophore spots developed on the opercle, just behind the pelvic fin base, and on the base of the dorsal fin. A faint row of melanophores along the mid-lateral part in the posterior half of the body is the first indication of silver band in the adult.
At 19.1 mm SL, the larva of this size begins to resemble the adult with the typical inferior mouth and conical head. The body is deepening and the alimentary tract has been almost integrated within the body, leaving the intestine still exposed. An elongated axillary scale has started to appear above the pectoral fin base. The last dorsal ray has moved forward to above or before the anus. A small median finfold remains just before the dorsal fin base.
Pigmentation: At this stage, pigmentation pattern is almost similar to the adult. Melanophores on the dorsal part of the head, on the opercle, along the midlateral part of the body and on the caudal fin have become more pronounced. All melanophores dorsal to the alimentary tract are now located higher on the body, being visible through the body wall. The melanophores characteristic of the adult are beginning to appear around the tip of the snout, on the tip of the lower jaw, both below and behind the eye, on the mid-dorsal line from the nape to the caudal fin base, and on the first 5 or 6 dorsal rays. |