Saturday, 7 January 2012

Missing Skull-Bones: Hidden Sea Dragon - A guest post by Jeff Liston.

Missing Skull-Bones: Hidden Sea Dragon – the true story of the Speeton Clay ichthyosaur
 or ‘Why really important specimens sometimes disappear for fifty years’.

This week, PLoS ONE published a paper which redrew the map as far as our understanding of ichthyosaur extinctions is concerned.  The news headline ‘No major ichthyosaur extinction at the end of the Jurassic after all’ might best summarise the conclusions.  Or (perhaps less accessibly) ‘Ophthalmosaurines alive and well and living in the Hauterivian of North Yorkshire’.  But some might find it odd that the holotype featured was from a specimen collected over fifty years ago from near Scarborough: if this was so special, why did noone pick up on it before?  Here is the answer – and sadly it is far from an atypical story.

The animal in question was found in the nineteen fifties by a group of postgrads at Hull University Geology Department.  At weekends they would hop on a train and go look for fossils. This particular weekend in Spring 1958, they were fossil-hunting in the Speeton Clay (Lower Cretaceous), and found an ichthyosaur.  Over succeeding weekends, they went back and recovered it, piece by piece, bringing it to Hull University, where it sat in their collections for some years, waiting for an ichthyosaur worker to look at it.  Enter Robert Appleby, Britain’s premier ichthyosaur worker in the fifties, sixties and early seventies, who borrowed some of the material (mainly skull, with some representative vertebral centra), intending to include it in the Handbuch der Palaoherpetologie, for which he was to do the ichthyosaur volume.

Then things became a little complicated. Margaret Thatcher’s government initiated the Earth Sciences Review (see The Earth Sciences Review Twenty Years On) at the end of the nineteen eighties, with the aim of saving money by cutting geology departments.  Despite Hull’s distinguished record as a department (and possibly due to a slightly biased assessment by a ‘hard rock’ worker from Oxford University), it was targeted for closure, and homes needed to be found for the collections housed by the department.  By this stage, one of the 1958 postgrads – Keith Ingham – was Curator of Palaeontology at the Hunterian Museum at the University of Glasgow.  He went back to Hull to pick up his research collections (he had become a world-renowned trilobite worker in the interim), and the Head of Department, John Neale, helped him recover his research material for transferral to the Hunterian.  In the process, the fate of the Speeton Clay ichthyosaur was raised – was it just going to be thrown in a skip? - and John made it clear that Keith, as one of the discoverers, could transfer that specimen as well.  Cue the ignominious transfer of an ichthyosaur to the back of a landrover, and a few hours later the specimen arrived in Glasgow.

Sadly, once there, it suffered from a similar problem to the one it had suffered in Hull: by the time I arrived at the Hunterian about 5 years later (in 1993), there had been no vertebrate specialists employed by the Museum for over eighty years, and the collection had fallen into some disarray.  As I sorted through the collections over the next ten to fifteen years, it became clear that the Speeton Clay animal, as an extremely rare Early Cretaceous ichthyosaur, was off everyone’s radar, and needed to be catalogued, numbered, described and published before I left.  Firstly, I had to recover the bones on loan to Robert Appleby – no mean feat, as he had retired from Cardiff University in the nineteen eighties to finish the Handbuch der Palaoherpetologie, and it was difficult to track down anyone who knew where he now was living.  Some months of research later, I had a telephone number. “Are you finished with the material?” “Not quite yet – I would hope to be soon….” I took to phoning Robert every 6 months, to encourage him to finish with the material as soon as possible.  Until one week in February 2004 when I phoned, to discover from his wife Valerie that he had died a few days earlier on the 8th.

Very soon after, I travelled down to recover the material that he had had on loan, and also received a request from Valerie to help with the posthumous publication of a variety of materials that Robert had been working on – most of which I am hoping to see enter publication this year.  Within the 500+ page monograph that he had completed the first draft of only a couple of days before he died, was a description of the Speeton animal within a general taxonomic review of the genus Platypterygius.  Having recovered the skull material on loan, and seeing how complete the specimen was, made me even more determined to see the specimen published – this was clearly something exceptional, which could easily get lost amongst the collections again.  I could write it up myself, but I knew that with my knowledge of ichthyosaurs being restricted to one genus – Ophthalmosaurus – I was unlikely to do justice to the specimen, and needed an ichthyosaur worker (thin on the ground these days) to do the job for me.  I started looking for a candidate, but in the meantime I gave the job of auditing the specimen to an Honours zoology student of mine, Jessica Tainsh.  After she completed the initial listing of elements present, I got her to incorporate the specimen into an existing character data set, in case a useful cladistic analysis might be possible.  One or two characters leapt straight out, that seemed to reinforce my impression that this was special – in particular a small peg-like structure on the basioccipital, a fairly rare character in ichthyosaurs.  By this time, I had seen Valentin Fischer present on Early Cretaceous ichthyosaurs at the European Association of Vertebrate Palaeontologists meeting in Aix-en-Provence in June 2010, and I knew that this was the person to describe the Speeton Clay ichthyosaur, as he had the breadth to place it in overall context and really do the job properly.  I began to hassle him – when was he coming to Glasgow to see the specimen?  By the end of 2010, I knew that I was going to be leaving the Hunterian the following year, and increased the pressure on him, sending him Jessica’s Honours project report through, and making it clear that he was unlikely to get the access that he required after I had left the Hunterian (they were already overstretched, and unlikely to employ a palaeontologist after I had left).  Eventually, he agreed to come in June 2011.

Valentin turned up at the Hunterian that week with his Apple laptop and expanding dataset – he had just finished a draft of a paper on an animal from Cremlingen, which a couple of ichthyosaur workers including Michael Maisch and Judith Pardo Pérez had also looked at with a view to writing up.  Within twenty minutes of looking at the Speeton Clay specimen, he said “Jeff, I think this is the same animal as in Cremlingen”.  With a ruthlessness that I am not entirely proud of, I asked him what he estimated the size of each animal to be – and he made clear that the German specimen was much smaller than the Speeton animal.  I smiled sweetly at him (it’s possible) and said “Well, it is clear that the German animal cannot be the type specimen, as it might be a juvenile.”  (The rationale is that characters that are juvenile might not be present in the adult form, so are not the safest for defining a taxon.) Valentin agreed – and that afternoon we started to look at possible names.  There were a number of striking adaptations throughout the skeleton that appeared to operate together to make the axial skeleton quite inflexible – a very robust rear of the skull; a remarkably solid scapula; an undulating perimeter to the vertebral centra which I had naively interpreted as preservation distortion, was actually a beautiful ‘locking’ mechanism to restrict axial flexion – and the concept of the ‘rigid swimmer’ was born.  In a nicely circular way, Keith Ingham (although retired from the Hunterian some ten years earlier) was very into the grammar and construction of fossil names, so he was my first port of call for suggestions as to how to translate the concept of ‘rigid swimmer’ into Greek.  While Valentin continued to score the specimen for characters in his expanded dataset, and started looking at rewriting the description he had previously based on the German animal, we batted back and forth some name ideas, discarding some for phonetic reasons, others for ‘overuse’ by other taxa.  After his week’s visit to the Hunterian was over, it was clear that the Speeton Clay animal would be written up as the holotype of the ‘rigid swimmer’, with the German specimen as secondary paratype material.

I then left the process to be steered primarily by Valentin and Darren Naish, who I knew were far better positioned to write an ichthyosaur paper than I, as I had a lot of work to finish before I finally left the Hunterian at the end of August 2011 – and thereafter I was on the road to a variety of conferences for some months, finishing up another couple of papers.  This is my way of trying to excuse the fact that I did not review or correct the final copy of the paper, where it transposes the last three digits of the holotype (the specimen is GLAHM 132855, not 132588).  Hey ho.  But with over 4,100 views of the paper in the last 5 days, the specimen at least now no longer languishes in anonymity within the collections of the Hunterian, and has finally achieved the status and recognition that it has so long deserved.

Thanks, Valentin – again, really good job.

And bear in mind that this is the first of three phases of ichthyosaur work that Darren, Valentin and I are hoping to publish this year, partly derived from Robert Appleby’s unfinished works – optimistically under the ‘brand identity’ of ‘Ichthyosaur Revolution’.  So stay tuned…..

Jeff Liston,
National Museums Scotland,
(also School of Earth Sciences, University of Bristol),

Upper image: GLAHM 132855, the Holotype of Acamptonectes densus.  (Ribs omitted to preserve the sanity of the curator - because he would have had to lay them all out and put them away again afterwards.) Photograph © and many thanks to Iona Shepherd.
Lower image: Acamptonectes densus Fischer et al., 2012, as reconstructed by C. M. Kosemen (contact 

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