These small sharks pose no threats to humans. The opposite, however, cannot be said.

Species name: Daggernose shark (Isogomphodon oxyrhynchus). Notable for their flattened snouts and relatively large fins, these small (1.5 meter) sharks are the only members of their genus.

Where found: The shallow coastal waters off of northeastern South America, where they predate upon schools of small fish.

IUCN Red List status: Critically endangered

Major threat: Overfishing, although most fishermen aren't targeting these sharks directly. Instead the sharks are caught in nets intended for other species. Two studies conducted in one Brazilian state in the 1990s found that daggernose sharks comprised as much as 10 percent of regional fish catches. The rate of fishing combined with the shark's slow reproductive rate has caused dramatic population declines. A 2002 study found that populations had dropped more than 90 percent over the previous decade.

Notable conservation programs: None that I could find. Heck, I couldn't even locate a photo of this species or any recent research about it. This critically endangered species could definitely use some targeted aid.

Image: An 1841 illustration from Systematische Beschreibung der Plagiostomen, which contained the first description of the daggernose shark. Public domain