fins and the paired fins, and with traces of 10 

 dorsal saddles appearing as areas of somewhat 

 intensified brown color; these saddles are obscure 

 or absent anteriorly in some adults. This color 

 pattern is so close to that of ScyliorMnus torrel 

 that specimens in a mixed lot of the two species 

 are not readily distinguishable from one another 

 on the basis of color. The other species of 

 Schroederichthys resembles ScyliorMnus boa in 

 general coloration, having a pattern of dark spots 

 spots and lines on a lighter background. 



Description of the holotype. — The holotype is 

 shown in figure 16A, and measurements are given 

 in table 5. Teeth in 24 + 2 + 24/(18 + ) +2 + 

 (18+) rows; most of them tricuspid but some 

 with additional small lateral cusps; largest upper 

 jaw teeth about 0.9 mm. high by 0.7 mm. in great- 

 est width, central cusp projecting beyond base 

 about five times length of lateral cusps, edges of 

 cusps smooth, six or more low surface ridges ex- 

 tending from bases about half-way toward tips of 

 cusps; lower jaw teeth similar but central cusps 

 somewhat lower, length of central cusp of largest 

 tooth about four times height of lateral cusps, sur- 

 face ridges very short, present only on lower por- 

 tion of the bases. 



Typical denticles of dorsalateral surfaces about 

 0.4 mm. long by about 0.2 mm. wide, with three 

 points directed upward and posteriorly, central 

 point much the longest, not very close set, with 

 skin surface showing around each denticle but 

 points overlapping, imbricate. 



Color of dorsolateral surfaces of bod}' light 

 brown with numerous round or oval spots of 

 lighter color, about half the length of the eye or 

 smaller and irregularly scattered; darker brown 

 dorsal saddles without definite darker edging 

 present but obscure anteriorly and extending to 

 fins only as a trace of darker color; no definite 

 spots on fins; ventral surfaces white, unmarked. 



Notes. — Sckroederichthys maculatus is known 

 from 48 specimens, all from the Caribbean con- 

 tinental slope of Central America off Honduras 

 and Nicaragua. The specimens were collected 

 from depths of 190 to 410 m., most of them near 

 Rosalind Hank and Quita Sueno Hank. The cap- 

 ture of more than .'ill specimens in one net haul 

 suggests that the species is locally abundant. 



Figure 17. — Schroederichthys maculatus 

 new species, ventral side of head of the 

 type, USNM 185556. 



Schroederichthys tenuis new species 



Figures 16 and 18 ; tables 1, 5, and 6. 



Holotype. — An immature male 230 mm. in total length, 

 USNM 188052, collected in a shrimp trawl at M/V 

 Oregon, station 2083 on November 17, 1957, from about 

 410 m. at lat. 01°49' N, long. 46°48' W., in the Atlan- 

 tic off the mouth of the Amazon River. 



Paratype. — An immature male 180 mm. long, USNM 

 188053, taken in the same haul with the holotype. 



Diagnosis. — Schroederichthys tenuis is known 

 only from the types, both immature males. There 

 appear to be no important differences in body 

 proportions between these specimens and speci- 

 mens of S. maculatus of comparable size. S. tenuis 

 is, of course, readily separable from sharks of other 

 genera. From S. maculatus, it differs greatly in 

 color pattern. In addition, S. tenuis has a nasal 

 flap longer than wide, and its tip is simply 

 rounded, not pointed or bilobed. The typical der- 

 mal denticles of dorsal surfaces in S. tenuis are 

 proportionally somewhat narrower than in S. ma- 

 culatus and more erect. Some have three pos- 

 teriorly directed points, but many of them lack 

 lateral points and are needlelike, although usually 

 showing a central ridge. The color pattern of S. 

 tenuis is made up of dark spots on a lighter 

 ground color, the spots assembled to form a series 

 of dorsal saddles. 



Description, of Iwlotype. — The holotype is 

 shown in fijrure 1BH and measurements are given 



606 



U.S. FISH AND WILDLIFE SERVICE 



