One of her colleagues called her because fisherman had preserved for her two rostra, of what they thought were sawfish," Weigmann says. The saw sharks were found with the help of a colleague Ruth Leeney from the Anderson Cabot Centre for Ocean Life, who had been researching new species of the related sawfish off the coast of Madagascar (sawfish are a type of ray, distantly related to sharks.)
On the other side of the Indian Ocean, German shark scientist Simon Weigmann of the Elasmobranch Research Laboratory in Hamburg helped to discover two new species of saw shark – bizarre-looking creatures armed with long snouts, or rostrums, studded with sharp teeth – off the south-eastern coast of Africa. The waters around Australia aren't the only ones offering up new shark species.
And I think there's another one in Western Australia, it's either new or it's a new record of a species poorly known from elsewhere in the world," says White. "I've got a feeling there's another one from Queensland, it's new, from the same genus. "We've actually found another new species of that same genus, also with ridged egg cases, but different ridged egg cases off Queensland. The demon catshark is not the only new catshark species to have turned up. Horn sharks tend to like living in shallow waters, often sitting on the seafloor in kelp forests, but this new species was found at 150m (500ft).īut that's nothing compared to what may lie ahead, White says. Another species, a type of horn shark, was caught in surprisingly deep waters off Western Australia in a survey last year. The demon catshark was not the only discovery White had a part in identifying recently. "The other thing, unfortunately, is you do get some specimens in collections that all you got is the fixed specimen, you don't actually have a fresh photo that demon catshark we described was lucky because we had a fresh photo as well." He says the current experts on this group of sharks all "liaise with each other and talk with each other" because identifying new species can be such a challenge. After being discovered during a survey at Rowley Shoals, the egg cases had been disseminated to museum archives without anyone looking much further into the cases' strange ridges. Will White, the senior curator of Australian National Fish Collection at CSIRO (Commonwealth Scientific and Industrial Research Organisation) in Hobart, Australia, was part of the team that connected the dots. Take the shark that laid the mysterious ridged egg cases, for instance. It is as much a by-product of painstaking work in the archives of museum collections as it is peering into the deep waters of the world's oceans. This new wave of discovery rivals that of the golden ages of exploration. Can technology save us from shark attacks?.There are more than 500 known species, and the numbers of new species show no signs of dropping off. As recently as the mid-1980s, science had settled on around 360 species of shark, ranging from deep sea featherweights like the 20cm (8in)-long dwarf lanternshark to the enormous plankton-feeding whale shark, the largest species of fish in the oceans.īut in little more than 40 years this number has jumped by nearly 40%. More than two decades into the 21st Century, humanity is still finding new species of the ocean's most impressive hunters. It would be more than 30 years before scientists would finally find out the most basic of these questions – and in doing so discover a completely new shark species.
What had laid them? Where did it live? And why did its egg cases have such a distinctive appearance? They offered up more questions than they did answers. The eggs had been found off the Rowley Shoals, a group of atolls on the edge of a continental shelf in the East Timor Sea, a few hundred kilometres off the north-eastern coast of Australia. The empty egg cases had one almost unique feature – a row of prominent ridges along the top. In 1989, scientists in Australia found a curious kind of "mermaid's purse" – a leathery egg case, which some species of sharks lay instead of giving birth to live young.
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