Koolasuchus – a strange creature from Cretaceous Victoria


Leslie Kool: Today we’re sitting on rocks that are 115 million years old and this area is situated about five kilometers from a little seaside town called Inverloch which is about 130 kilometers south east of Melbourne. We’re actually digging at a fossil locality in this area -the Dinosaur Dreaming dig have been coming here for the last 17 years digging out an area on the shore platform where we are finding hundreds of bones.

Mike Cleeland: first found the bones of Koolasuchus in late April 1990 and it was the shock of my life, I’d never seen a bone that big. I could see this thing embedded in the rock and I’d found other pieces of dinosaur bone and other bones referable to the same species but I had never seen anything of that size. But it wasn’t until we actually extracted it out and got it into the museum and got it positively identified that I realised that this is what it was, that it was the jaw bones of one of the giant amphibians. 

Leslie Kool: Koolasuchus first came into my life in a big block that arrived at the palaeo lab at Monash University after it was excavated by Mike and his crew and when I first saw it I could see one of the jaws that was exposed on the outside. But we really had no idea what was in there and it took me three months of painstakingly chipping away the rock really carefully to expose what turned out to be two whole jaws inside the blocks and it was a very satisfying job because I hadn’t expected anything to be that spectacular inside that rock.

Mike Cleeland: Because the animal is essentially structurally similar to a tadpole, if you imagine for instance a tadpole with ah, which still has the four legs and the tail and instead of turning into a frog it just keeps growing. So you have this animal which is essentially a giant carnivorous tadpole wondering around the Cretaceous rivers and lakes and just swallowing up little dinosaurs or whatever it can get its teeth into.

Leslie Kool: Koolasuchus cleelandi was a.. what we call a temnospondyl amphibian, which was an ancient amphibian that lived in the rivers of the valley that existed in this area. It was about the size of a saltwater crocodile, maybe up to five metres long, and an enormous shovel-like head approximately a metre in diameter. So this was a top predator in the rivers.

Mike Cleeland: Yeah, it’s a source of great pride to have a fossil named after you, we’re talking about Koolasuchus cleelandi and my name is Mike Cleeland and the specimen is jointly named after myself and Leslie Kool.

Leslie Kool: Koolasuchus means Kool’s crocodile and I’m very fortunate to have my surname as Leslie Kool. And so I was given the honour of having this amazing big mouth predator named after me. So it is a great honour.

About this Video

Leslie Kool and Mike Cleeland describe their roles in finding and preparing the fossil of Koolasuchus, an amphibious carnivore.
Length: 03:08