Identifying Baryonyx /Baryonychinae Theropod Teeth from UK

[Troodon]

Edited 10/2/21

 

Came across an interesting short paper that I thought would interest those of you that collect in the UK or acquire theropod material from that region

The paper by Denver Fowler talks about how Baryonychid teeth are often misidentified as crocodilian which are similiar in appearance. In fact museum specimens identified has such were Baryonychid.

Width, curvature, denticles and surface texture are the characteristics used for the identification. It's best to study the paper, not a bad read and great photos to help you.

 

https://www.researchgate.net/publication/271217531_Recently_rediscovered_baryonychine_teeth_Dinosauria_Theropoda_New_morphologic_data_range_extension_similarity_to_Ceratosaurus

 

Two new Baryonychinae have been described from the Wessex Formation (Barremian) of the Isle of Wight.   Identification of teeth belonging to Baryonyx will be difficult if they are found in Barremian deposits.  The best ID for this morphology would be Baryonychinae indet.

 

https://www.nature.com/articles/s41598-021-97870-8

 

[Welsh Wizard]

Interesting paper. Thanks for the link.

I've a couple of thoughts on the paper:

To me, some of the teeth do look like plesiosaur/pliosaur teeth.

Also, it's been long known amongst collectors that you get Baryonyx teeth/bones from the Hastings units. You even see some for sale on eBay. I'm not sure if much work has been done on these specimens but it would be interesting to know.

With respect to the naming. How would that work. The paper describes the academic/theoretical position wrt naming convention, but the reality is that Suchosaurus has been named from scrappy material whereas Baryonyx is well represented as a skeleton.

Regards

Nick

[Troodon]

The teeth have some resemblances to ples/plio but the robustness, ridges and curvature is different. With their food source primarly marine you would expect some similarities.

With naming I stay clear from that because I always get confused to what is really the oldest recognized taxon. I'll let others decide and nod my head.

[Troodon]

Key Features From Paper

 

Surface texture

Granular/wrinkled enamel.  The surface texture of  baryonychine teeth  is described as “finely  granular”  (Charig & Milner,  1997),  and was not  seen to  vary  amongst  observed  specimens.  The texture is unlike  other theropod dinosaurs  and crocodylomorphs,  but  not  unlike  that seen in sauropods.

 

Denticles

Baryonychines are characterized as possessing very fine denticles (~7 per mm, Charig & Milner, 1997) running from the apex to the base of the crown on both mesial and distal carinae. By comparison, denticles are absent from crocodylomorphs

 

From UK tooth

 

From Portugal

 

 

Longitudinal  fluting and/or faceting

 

A  ‘typical’  baryonychine  tooth possesses 6-7  ridges and flutes  (“ribs” of  Buffetaut, 2007) concentrated towards the centre of  the lingual side of  the crown,  with the enamel  smoothening out  towards  the carinae.  Ridges  are sometimes present  on both lingual and labial sides  (Fig.  6).  In specimens observed that  show  this character,  the crowns have always  been conical,  with poor lateral  compression. Conversely,  sometimes fluting is absent  from  both sides of  the crown (Fig.s  5). When ridges are not  present,  they  are instead replaced by  a flat  faceted surface (Fig.  7),  or just  a typically  theropodan smooth surface (Fig.s  4  & 5).  Teeth  lacking fluting  tend to  be more  laterally  compressed.  This  is unlike the condition in goniopholid  teeth,  where  ridges are  much finer and  extend almost  to the unserrated carinae.