

^^^^^^H 



Figure 23. —Lateral view of portion of caudal fin of 

 Apristurus profundorum (Goode and Bean), showing 

 closely packed denticles on and near the upper margin 

 of the tin and the widely spaced denticles on the lateral 

 surfaces of the tail. 



Apristurus indicus (Brauer), 1906 



Figures 9, 22, and 27 ; tables 1, 7, and 8. 



It is clear that the western Atlantic specimens of 

 Apristurus at hand may be divided into four 

 groups on the basis of characters given in the pre- 

 ceding key. Three of these groups of specimens 

 clearly represent respectively Apristurus profun- 

 dorum (Goode and Bean), J., riveri Bigelow and 

 Schroeder, and A. laurussoni (Saemundsson). 

 The fourth group includes specimens referred to 

 Apristurus atlanticus (Koefoed) by Bigelow and 

 Schroeder (1948) and Bigelow, Schroeder, and 

 Springer ( 1953) . The specimens available for ex- 

 amination are about 40 examples from the Gulf of 

 Mexico, the Caribbean, and adjacent Atlantic wa- 

 ters, most of them immature. All are referred to 

 Apristurus indicus (Brauer) with some missgiv- 

 ing because A. indicus has been regarded as 

 restricted to the Indian Ocean. 



Koefoed states (1927) that atlanticus is related 

 both to profundorum Goode and Bean, and indicus 

 Brauer, but that it differs in having a larger eye. 

 From Koefoed's measurements of the type, a 247- 

 mm. specimen from the Atlantic near Gibraltar, it 

 can be calculated that the orbit is 4.9 percent of the 

 total length. Among the specimens referred here 



to A. indicus, the orbit is 2.5 to 4.0 percent of the 

 total length and in available specimens of other 

 Atlantic species 2.2 to 3.9. Koefoed's figure of the 

 type of atlanticus (1927, pi. 3, fig. 3) shows the 

 second dorsal fin only slightly larger in area than 

 the first. In Western Atlantic specimens of A. 

 indicus the second dorsal fin has less than half the 

 area of the first dorsal. Furthermore, Koefoed 

 specifically states that the first and second dorsal 

 fins of atlanticus are equally large. 



The number of tooth rows in the western North 

 Atlantic specimens of A. indicus at hand varies 

 from 33 + 33/33 + 33 to 45 + 45/45 + 45. The teeth 

 of these specimens are much smaller and more 

 numerous than in A, profundorum and A. riveri. 

 Although the teeth of A. laurussoni are slightly 

 larger than in the A. indicus specimens, the differ- 

 ence is not great enough to be notable except on 

 direct comparison of specimens of equal size. 



Apristurus riveri Bigelow and Schroeder, 1944 



Figures 4, 5, 7, 10, 11, 24, and 27 ; tables 1, 7, and S. 



In one haul with a 40-foot shrimp trawl at M/V 

 Oregon station 3586 off the Caribbean coast of 

 Panama, five Apristurus of about equal size were 

 taken. The haul was made in 860 to 914 m. A 

 temperature determination at the bottom was not 

 made at this station but in nearby stations the fol- 

 lowing temperatures were recorded : 366 m., 11.6° 

 C ; 457 m., 8.8° C ; 750 to 768 m., 5° C. Four of the 

 specimens collected were adults of A. riveri, one 

 male and three females. The fifth specimen was 

 an immature example of A. indicus. Of the three 

 female riveri, one had short filamentous processes 

 of egg cases protruding. In all three the cloacal 

 area was surrounded by a flattened ring of white 

 tissue. All had large eggs ( 10-12 mm. diameter) 

 in the single ovary, and one had egg cases with 

 eggs in both oviducts. The egg cases were about 

 50 mm. long, not including filaments, and about 

 15 mm. in greatest width. The shells appeared to 

 be smooth surfaced. The egg shells were not com- 

 pletely formed or finished at their inner ends, and 

 the nature of the processes at the posterior ends 

 could not be determined, except that they were not 

 the single tendrils at each corner found in 

 Scyliorhinus but were more numerous and ar- 

 ranged as a filamentous fringe across the end of 

 the case. The cases were greenish, semitranspar- 

 ent, and with some longitudinal lines of lighter 

 color. 



REVIEW OF WESTERN ATLANTIC CAT SHARKS 



613 



