Initial excavation of a site on the Svalbard islands in August yielded the remains, teeth, skull fragments and vertebrae of a reptile estimated to measure nearly 40 feet long, said paleontologist Joern Harald Hurum of the Natural History Museum at the University of Oslo.
"The new monster we found this year is of the same species as the one we excavated this year (and found last year) there are not two new species of large pliosaurs but one," Hurm told CBSNews.com via e-mail.
His team described those 150-million-year-old remains as belonging to a short-necked plesiosaur measuring more than 30 feet - "as long as a bus ... with teeth larger than cucumbers."
The short-necked plesiosaur was a voracious reptile
Mark Evans, a plesiosaur expert at the Leicester City Museums in Britain, said he not know enough about the Norwegian find to comment on it specifically. But he said new types of the sea reptiles are being found regularly.
"We are regularly seeing new species of plesiosaurs popping up - in a way because, in the past 10 or 15 years, there has been what we call a renaissance in plesiosaur research," Evans said by telephone.
Hurum said the team had only managed to excavate a 3-yard area of the find. The Norwegian-led team plans to present more detailed findings early next year, and return to Svalbard, 300 miles north of Norway's mainland, to excavate further next year.