REVISION OF CARCHARHINID SHARK GENERA — SPRINGER 627 



Additional material : east indian archipelago: BMNH [no num- 

 ber] (1 : 430) ; USNM 40029 (1 : 355; this specimen is listed in the cata- 

 log as questionably from Queensland, Australia; I believe it did not 

 come from Australia). 



Rhizoprionodon (Protozygaena) taylori (Ogilby) 



Figure 14 



Physodon taylori Ogilby, 1915, Mem. Queensland Mus., vol. 3, p. 117 (Towns- 

 ville, north Queensland). 



Diagnosis. — (Not until this study was in an advanced stage was it 

 realized that R. taylori and R. oligolinx were separate species; the 

 description that follows is deficient because most of the material 

 examined was not available to me during the writing.) Upper labial 

 furrow poorly developed, 0.7-1.1 percent of t.l.; precaudal centra not 

 obviously elongate in posterior monospondylous region (as in plate 

 2c) ; precaudal vertebrae greater in number than caudal vertebrae ; 

 anterior margin of pectoral fin shorter than total length of first dorsal 

 fin; snout in front of nostrils 4.0-5.0 percent of t.l. in specimens less 

 than 575 mm. t.l. (5 specimens measured), 4.2 percent of t.l. in speci- 

 mens over 575 mm. t.l. (2 specimens measured) ; total teeth in outer 

 row of upper jaw 24-25 (24 in 8 out of 9 specimens); total teeth in 

 outer row of lower jaw 21-23 (22 in 8 out of 9 specimens); total en- 

 larged hyomandibular pores on both sides of head usually more than 

 16 (6 out of 8 specimens) ; first dorsal fin origin over level of appressed 

 pectoral inner corner; origin of second dorsal fin ranges from over 

 posterior fourth to over posterior sixth of anal base; tip of appresssed 

 pectoral fin reaches to below level of anterior third or less of first 

 dorsal base. Only two males seen, ca. 310 and 407 mm. t.l., both 

 immature; clasper length in latter 4.8 percent of t.l. 



Description (see table 17). — Precaudal vertebrae 73-80; caudal 

 vertebrae 62-70; total vertebrae 135-149; cusps of teeth smooth to 

 faintly irregular; posterior bases sometimes denticulate; enlarged 

 hyomandibular pores 7-1 1 on each side of head. 



Denticles imbricate, 3- to 5-ridged and 3-toothed or irregularly 

 margined (based only on USNM 174075). 



Color of preserved specimen (USNM 174075): Body brownish gray 

 above, pale below. Pectorals darker than body color with a pale 

 distal margin; pelvics and anal somewhat lighter than pectorals; 

 caudal paler than body, without black edging on upper lobe; pale 

 posterior edge on lower lobe; first and second dorsal fins about same 

 color as body dorsally. 



Interdorsal ridge present or absent. Both precaudal pits present, 

 the upper better developed. 



