Porstlarval Scombroids from the Central Pacific — STRASBURG 
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FIG. 3. Nealotus tripes 9.0 mm in standard length. 
but are free from the last dorsal ray. The same 
is true of the anal finlets, except that there is a 
persistent basal membrane between the last anal 
ray and the first finlet. The dorsal spines have 
lost the spinules from their anterior edges, and 
the lateral spinules are less prominent on all 
fin spines, the space between the spinules having 
become filled with bony material. The pelvic 
rays are both buried in epidermal tissues, with 
the short mesial ray lying deeper than the long 
lateral one. 
The upper spine at the preopercular angle is 
prominent, but the lower is broad and scarcely 
noticeable. The lower preopercular limb is 
smooth, and the opercular spines are reduced in 
size. The cartilaginous protuberance at the tip 
of each jaw is conical and well developed. The 
dentary has 2 anterior fangs and 13 variably 
smaller teeth; the premaxillary bears 3 anterior 
fangs and about 16 smaller teeth. The vomer 
has 2 teeth on each posterior tip, and there are 
about 6 teeth on or near each palatine. As 
before, some of the latter are attached to un- 
ossified material on the roof of the mouth. 
There are 3 + 1 + 8 gill-rakers on the first 
arch, the one at the angle being much larger 
than the others. 
A new feature is the lateral line, a few scales 
of which are visible on the 31-mm fish. These 
lie in the skin and are better developed and 
more numerous anteriorly. In a 3 5 -mm speci- 
men (not shown) the lateral line is nearly 
completely developed. It is a tubelike structure 
containing 78 scales and extending from the 
head to the caudal peduncle. Scale spacing is 
occasionally irregular, suggesting incomplete de- 
velopment or loss through damage. 
Pigmentation consists of rows of tiny, close- 
set, dark dots, giving an over-all tan color. This 
is intensified on top of the head, at the jaw 
tips, along the dorsal base, on the sides of the 
caudal peduncle, and around the anal spines. The 
fins lack pigment except for a distal dark spot 
between the first three dorsal spines. 
A 4 1.5 -mm fish (Fig. 6) is essentially a 
juvenile. Persistent larval features include the 
slightly denticulate fin spines, the absence of 
scales except in the lateral line, and basal mem- 
branes between the finlets. The pelvic rays are 
embedded, the two preopercular and two oper- 
cular spines are reduced in size, and the sym- 
physial jaw pads are less prominent (and now 
decurved in the case of the upper jaw). The 
teeth have increased slightly in number, there 
now being 3 anterior fangs and 19 lateral 
teeth on the premaxillary, 2 fangs and 16 lateral 
teeth on the dentary, 8 or 9 teeth on each palatine 
(all firmly ankylosed to the palatine and none 
free on the roof of the mouth), and 1 or 2 
elongate teeth posteriorly on each side of the 
vomer. There are 94 scales in the lateral line 
but none elsewhere. There are 3 + 1 + 8 
slender gill-rakers on the first arch. Pigmentation 
is as in the 31-mm fish, except that there are 
now indications of distal dark spots between 
the first four dorsal spines. 
