"The blacknose shark has a slender, streamlined body with a long, rounded snout and large eyes. There is a well-developed flap of skin in front of each nostril, defining the inflow and outflow openings. There are 12–13 and 11–12 tooth rows on either side of the upper and lower jaws respectively, with 1–2 teeth at the symphysis (middle). The teeth are triangular and oblique, with serrated edges; the upper teeth are stouter than the lower teeth. The five pairs of gill slits are short, measuring less a third the length of the first dorsal fin base.[6][8]
The first dorsal fin is small and somewhat falcate (sickle-shaped), with a pointed apex and a short free rear tip; its origin lies over the free rear tips of the pectoral fins. The second dorsal fin is relatively large, though still less than half the height of the first. There is no ridge between the dorsal fins. The pectoral fins are short and tapered.[8] The body is covered with overlapping dermal denticles that bear 5–7 longitudinal ridges (3 in very young individuals) leading to 3–5 marginal teeth.[6] The coloration is yellowish to greenish gray or brown above and white to yellow below. There is a distinctive dark blotch at the tip of the snout that is most obvious in young sharks. The tips of the second dorsal fin, upper caudal fin lobe, and sometimes the lower caudal fin lobe, are dark. Blacknose sharks are typically 1.3–1.4 m (4.1–4.6 ft) long and 10 kg (22 lb) in weight.[2][8] The maximum length and weight on record is 2.0 m (6.6 ft) and 18.9 kg (42 lb) respectively.[9]
Sources
1.^ a b c d e f g Morgan, M., J. Carlson, P.M. Kyne and R. Lessa (2008). Carcharhinus acronotus. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on January 19, 2010.
2.^ a b c d e f Compagno, L.J.V. (1984). Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date. Rome: Food and Agricultural Organization. pp. 454–455. ISBN 9251013845.
3.^ Naylor, G.J.P. (1992). "The phylogenetic relationships among requiem and hammerhead sharks: inferring phylogeny when thousands of equally most parsimonious trees result". Cladistics 8: 295–318. doi:10.1111/j.1096-0031.1992.tb00073.x.
4.^ Dosay-Akbulut, M. (2008). "The phylogenetic relationship within the genus Carcharhinus". Comptes Rendus Biologies 331 (7): 500–509. doi:10.1016/j.crvi.2008.04.001. PMID 18558373.
5.^ Stafford-Deitsch, J. (2000). Sharks of Florida, the Bahamas, the Caribbean and the Gulf of Mexico. Trident Press. p. 68. ISBN 1900724456.
6.^ a b c d e f g h i Bester, C. Biological Profiles: Blacknose Shark. Florida Museum of Natural History Ichthyology Department. Retrieved on June 2, 2009.
7.^ a b c d Driggers, W.B. (III), Ingram G.W., (Jr.), Grace, M.A., Carlson, J.K., Ulrich, J.F., Sulikowski, J.A. and Quattro, J.M. (2007). Life history and population genetics of blacknose sharks, Carcharhinus acronotus, in the South Atlantic Bight and the northern Gulf of Mexico. Small Coastal Shark Data Workshop Document, SEDAR-13-DW-17.
8.^ a b c McEachran, J.D. and Fechhelm, J.D. (1998). Fishes of the Gulf of Mexico: Myxiniformes to Gasterosteiformes. University of Texas Press. p. 74. ISBN 0292752067.
9.^ Froese, Rainer, and Daniel Pauly, eds. (2009). "Carcharhinus acronotus" in FishBase. June 2009 version.
10.^ Musick, J.A. and McMillan, B. (2003). The Shark Chronicles: A Scientist Tracks the Consummate Predator. Macmillan. pp. 57–59. ISBN 0805073590.
11.^ May, N. and Willis, C. (2002). Shark: Stories of Life and Death from the World's Most Dangerous Waters. Thunder's Mouth Press. p. 192. ISBN 1560253975.
12.^ Hueter, R.E., Heupel, M.R., Heist, E.J., and Keeney, D.B. (2005). "Evidence of Philopatry in Sharks and Implications for the Management of Shark Fisheries". Journal of Northwestern Atlantic Fishery Science 35: 239–247.
13.^ Martin, R.A. (March 2007). "A review of shark agonistic displays: comparison of display features and implications for shark-human interactions". Marine and Freshwater Behaviour and Physiology 40 (1): 3–34. doi:10.1080/10236240601154872.
14.^ Cressey, R.F. (1970). "Copepods Parasitic on Sharks From the West Coast of Florida". Smithsonian Contributions to Biology 38: 1–30.
15.^ Ruhnke, T.R. and Thompson, V.A. (2006). "Two New Species of Paraorygmatobothrium (Tetraphyllidea: Phyllobothriidae) from the Lemon Sharks Negaprion brevirostris and Negaprion acutidens (Carcharhiniformes: Carcharhinidae)". Comparative Parasitology 73 (1): 35–41. doi:10.1654/4198.1.
16.^ Healy, C.J. (2003). "A revision of Platybothrium Linton, 1890 (Tetraphyllidea: Onchobothriidae), with a phylogenetic analysis and comments on host-parasite associations". Systematic Parasitology 56: 85–139. doi:10.1023/A:1026135528505. PMID 14574090.
17.^ a b Driggers, W.B. (III), Oakley, D.A., Ulrich, G., Carlson, J.K., Cullum, B.J. and Dean, J.M. (2004). "Reproductive biology of Carcharhinus acronotus in the coastal waters of South Carolina". Journal of Fish Biology 64 (6): 1540–1551. doi:10.1111/j.0022-1112.2004.00408.x.
18.^ a b Hazin, F.H.V., Oliveira, P.G. and Broadhurst, M.K. (2002). "Reproduction of the blacknose shark (Carcharhinus acronotus) in coastal waters off northeastern Brazil". Fishery Bulletin 100: 143–148.
19.^ a b Ferrari, A. and Ferrari, A.. Sharks. Firefly Books. p. 157. ISBN 1552096297.
20.^ "NOAA Proposes Measures To Rebuild Blacknose And Other Shark Populations". (July 24, 2009). NOAA – National Oceanic and Atmospheric Administration. Retrieved on July 26, 2009.