Siamosaurus tooth or croc tooth from Thailand

[msantix]

Hi,

 

Was wondering if this tooth from the Sao Khua Formation in Thailand is from the Spinosaur Siamosaurus or if it is a croc tooth. The tooth is 3cm long. Thanks.

 

[Troodon]

I'll make the following comments.  I compared this tooth to those in my collection and to the holotype shown below.  The differences are as follows: the vertical ridges extend to the base unlike your example.  They also appear much closer together than your example, Buffetaut & Ingavat (1986): state that there are 15 ridges per side.   The shape is also more banana like than stubby.   I don't know if there are other morph types of Thai spinosaurid teeth but this one does not fit the ones I've seen.  Good call to have it checked out.

 

 

A catalogue of material and review of the Spinosauridae
December 2010PalArch's Journal of Vertebrate Palaeontology 7(4)