It gets its name from, you guessed it, a black spot under its little snout. Interestingly enough, its caudal peduncle has no keel.
"What a caudal peduncle?"
Lets look at this fish to get an idea of what the caudal peduncle is:
Blacknose sharks are only found in coastal, tropical waters of the western Atlantic Ocean including the Caribbean Sea, Bahamas, and Gulf of Mexico.
These animals are segregated by size and sex with juveniles found in shallow waters (probably for protection) and adults found in deeper waters of 9+ meters (30+ ft). They are known to form schools and can be found feasting on mullet and anchovies. As fast swimmers, they also feed on pinfish, croakers, porgies, spiny boxfishes and porcupine fish. It's also known to snack on the occasional octopus. Their upper teeth are narrow and triangular, allowing for the spearing of the slippery fish. The lower teeth are serrated and broad.
Mating season is known for blacknose sharks, with them getting together in May/June and, once pregnant, having a gestation period of 11 months. It seems that these sharks have two different reproduction cycles in the Northwestern Atlantic and Gulf of Mexico; observations show female blacknose sharks in the Gulf of Mexico reproduce annually, while those in the Atlantic appear to reproduce biennially (once every 2 years). More research needs to be done on this. Litter size ranges from 3-6, but is usually 4. Bulls Bay, South Carolina (in the USA) is a known nursery area.
Like many sharks, they are preyed upon by larger sharks. Dusky sharks (Carcharhinus obscurus) in particular like to have blacknose shark for a snack.
They are fished recreationally as they put up a good fight. Commercially, they are known to be dried, salted and smoked. They pose little threat to humans, and have never been recorded in an "attack," however divers do report blacknose sharks displaying threatening poses (hunched back with head raised and caudal lowered). If this does happen, leave the water immediately by swimming away from the animal in smooth strokes, eyes always on the shark.
The blacknose shark is currently listed as Near Threatened (NT) by the IUCN.