NEW GIANT PLIOSAUR

["Darren Naish" <dwn194@soton.ac.uk>]

Colin McHenry and Dr. David Martill were on Radio 4's 'Natural History
Programme' last friday, announcing the rediscovery of a pliosaur *bigger* than
any known specimens of _Kronosaurus_ or _Megalneurosaurus_ (the latter a very
scrappy taxon anyway), the previous record holders. 

The animal is represented by a vertebra found in Peterborough. It was painted
blue and used a doorstop until someone finally decided to hand it in to
Peterborough Museum. There it was identified as a _Cetiosaurus_ vertebra, and
has been languishing as such for quite some time. On seeing this specimen
recently, Colin realised its importance. It is 40-50 % bigger than comparable
material of _Kronosaurus queenslandicus_ - itself about 13 m or so long - and
may therefore have been 20 m long! 

(Colin recently showed me a photo of a pliosaur snout tip that appears to have
come from a correspondingly huge animal.)

PLIOSAURS TO RIVAL BLUE WHALES?

Martill speculates that this isn't an upper size limit. In recent years we've
been seeing an upward extension of sauropod maximal sizes, and it's clear that,
in the Mesozoic, dinosaurian giants got far bigger than anything the mammals
could achieve. A puzzle is that, conversely, marine mammals have reached
extraordinary sizes (up to 200 tons and 30 m in _Balaenoptera musculus_) whereas
the Mesozoic marine reptiles never did. But perhaps they _did_ after all. I
would guess that a 20 m pliosaur could weigh upwards of 60 tons, and if they got
bigger than that, we do have marine reptiles in the big baleen-whale range. 

Of course, a marine macropredator the size of a large whale _is_ quite an image.
_I_ wouldn't enjoy a swim in the Jurassic seas.. neither would a large dinosaur.

My secretary is currently preparing a transcript of the item, and I hope to post
it within the week.

"But first we must eat, come, good food, come..."

DARREN NAISH
dwn194@soton.ac.uk