(CNN)Scientists have identified two new species of shark that live in the depths of the West Indian ocean.
Two new shark species have been identified and they look like nothing you've seen before
The new species are six-gill sawsharks, which have distinctive snouts filled with teeth and catfish-like whiskers or feelers that help them detect prey.
One, Pliotrema annae, was discovered after being caught by fishermen in Zanzibar, while the snouts of the other species, known as Pliotrema kajae, were collected in Madagascar, with other specimens later found in museum collections.
Neither of the two shark species have been spotted alive in the wild.
"We were conducting shark and ray research with those fishers at the time and realized that these sawsharks did not match the existing species," said study author Andrew Temple, a research associate at Newcastle University in the UK.
"We have collected two so far - they are not common."
Temple said the discovery, published Wednesday in the journal PLOS One, showed "how important the western Indian Ocean is in terms of shark and ray biodiversity, but also how much we still don't know."
"The region is widely understudied, with the majority of what we know coming from work in fisheries. The difficulty is that small-scale fisheries dominate the region - with at least half a million fishers using 150,000+ vessels," he said via email.