SYDNEY, June 16 (Xinhua) -- Scientists in Australia have identified a previously unknown species of walking shark during fieldwork in Papua New Guinea (PNG), marking a rare addition to the group.
Researchers discovered the meter-long Dudgeon's walking shark, named after Australia's University of the Sunshine Coast (UniSC) senior research fellow Christine Dudgeon, in shallow waters off Milne Bay, southeastern PNG, according to a UniSC statement released on Tuesday.
It is the first new species described in the genus since 2013, according to a study published in the Journal of the Ocean Science Foundation. The research confirmed that the nocturnal shark is found only in a small area off southeastern PNG.
"The sharks, which eat invertebrates off the sea floor and are not dangerous to humans, are famous for using all four fins as limbs to amble across reef flats at low tide," the statement said.
The shark was first spotted by researchers studying endangered epaulette sharks. Lead author Jess Blakeway, a UniSC PhD student, said its distinctive white dashes along its brown body differed from "the leopard-like spots" of related species. Genetic analysis later confirmed it as a new species.
The species' local name, kadedekedewa, roughly means dog shark or lazy shark, referring to its slow, four-limbed gait.
The newly identified species appears to have a highly restricted range, raising concerns about vulnerability to habitat degradation, fishing pressure and climate change. Researchers plan further surveys to support an International Union for Conservation of Nature (IUCN) assessment.
The discovery brings the number of known walking shark species in the region to 10. Five are already listed as threatened with extinction by the IUCN, tied to their restricted range, a criterion that applies to just 3 percent of all sharks, Blakeway said. ■
