. Bulletin. Natural history; Natuurlijke historie. Fig. 34. S. saginatus. A, camera lucida drawing of dorsal ridge scales of YPM 8932, holotype; B, camera lucida drawing of frontals, YPM 8929. Scale = 1 cm. Description. The dorsal ridge scales of S. saginatus are globular (Fig. 34). In the holotype, the first 3 dorsal ridge scales are only slightly enlarged, slightly convex, and almost radially symmetrical with no spine. The 4th scale is like the first three but much larger and more convex, radially symmetrical, and lacking a spine. The 5th through 12th scales are large, with bulbous bases and
. Bulletin. Natural history; Natuurlijke historie. Fig. 34. S. saginatus. A, camera lucida drawing of dorsal ridge scales of YPM 8932, holotype; B, camera lucida drawing of frontals, YPM 8929. Scale = 1 cm. Description. The dorsal ridge scales of S. saginatus are globular (Fig. 34). In the holotype, the first 3 dorsal ridge scales are only slightly enlarged, slightly convex, and almost radially symmetrical with no spine. The 4th scale is like the first three but much larger and more convex, radially symmetrical, and lacking a spine. The 5th through 12th scales are large, with bulbous bases and prominent spines covered with ganoine. The spines do not overlap the next scale in the series. Scales 13- 20 have flatter, smaller bases and more prominent spines. The 21st scale is the spineless predorsal scale. In most individuals, the posterior 5 scales in the series have spines that look like the anterior scales in the S. micropterus group (Olsen and others 1982). At least one spine in the posterior region of YPM 8932 is elongated, and several are definitely short (not broken). Whether the remaining posterior scales are short spined or just broken is ambiguous. If real, the short spines may be an anomalous variation as the spines are prominent on posterior scales in other specimens of S. saginatus. The general form of the dorsal ridge scales is similar to those of S. greenwoodi and S. fundus but less prominent than those of S. profundus, S. tenuiceps, and S. decoratus. S. saginatus is deeper bodied than all but S. profundus, but in the former, a greater proportion of this body depth is ventral to the lateral line (Figs. 27, 29D, E). The slope of the skull roof is about 35-40° relative to horizontal. The dorsal fin is more posteriorly placed than in .S'. profundus. Morphometric data are sum- marized in Table 31. There are 33-35 lateral line scales. The pelvic, anal, and dorsal fin positions are at rows 7-9, 17-19, and about 21, respectively. There are about 11 scales betwe
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