Identification of Spinosauridae Teeth from Northern Thailand and Laos

[Troodon]

I see more and more material being made available from Laos especially Spinosauridae teeth and members asking about them.  I'm not an expert from this locality just trying to pull together published information to help collectors on both Thailand and Laos teeth.  Its never simple .

 

Locality is very important in identification, so you really need to know the specific area where the teeth were found.  Just Laos or Thailand is not acceptable

 

Lets look at Localities and formations

 

Nice image from the paper that described a Garfish that shows both Thailand and Laos localities (Cavin 2019)

 

 

 

 

Northeastern Thailand

 

Khok Krut Formation:  

Morph type 1 : Spinosaurid indet

Morph type II : cf Simosaurus suteethorni

 

(Manitkoon et al 2022)

The teeth of Khok Kruat spinosaurids (see below figure) can be categorized into two sub-morphotypes (Wongko et al. 2019), both found in the Khok Pha Suam locality. Sub-morphotype I (Fig. 3p) presents a smooth enamel surface of the crown and possesses more than 20 fine ridges on each side. Sub-morphotype II (Fig. 3q) shows a wrinkled enamel surface of the crown and no more than 16 coarse ridges on each side, which is similar to Siamosaurus suteethorni from the Sao Khua Formation  

 

 

Morph Types  figure 3 

 

 

 

From  (Wongo et al 2019)

 

Sao Khua Formation:

 

A: Siamosaurus suteethorni tooth (Sao Khua Fm)

B: Indet Spinosaurid (Khok Kruat Fm)

 

Summary of known teeth from different areas ( Wongo et al 2019 )

 

 

Laos:

The Gres superieurs Formation:

-From Savannakhet basin

-Ichthyovenator laosensis is considered a Spinosaurinae (Allain et al 2014)

-No teeth were found with the Holotype of Ichthyovenator so they were not described as part of that publication

-The Grès Supérieurs Formation of southern Laos is laterally considered an equivalent to the Khok Kruat Formation.   (Manitkoon et al 2022)

-KEY: Morph type I from above considered Ichthyovenator laosensis   (Manitkoon et al 2022)

 

 

References:

 

-Spinosaurid theropod teeth from the Red Beds of the Khok Kruat Formation (Early Cretaceous) in Northeastern Thailand , Kamonlak Wongo, Eric Buffetaut, Suchada Khamha and Komsorn Lauprasert 2019

 

-The first definitive Asian spinosaurid (Dinosauria: Theropoda) from the early cretaceous of Laos Ronan Allain & Tiengkham Xaisanavong & Philippe Richir & Bounsou Khentavong 2012

 

-Fossil assemblage from the Khok Pha Suam locality of northeastern, Thailand: an overview of vertebrate diversity from the Early Cretaceous Khok Kruat Formation (Aptian-Albian) , Sita Manitkoon, Uthumporn Deesri, Komsorn Lauprasert, Prapasiri Warapeang, Thanit Nonsrirach, Apirut Nilpanapan, Kamonlak Wongko, Phornphen Chanthasit 2022

 

-A spinosaurid from Thailand (Sao Khua Formation, Early Cretaceous) and a reassessment of Camarillasaurus cirugedae from the Early Cretaceous of Spain,  Adun Samathi , P. Martin Sander & Phornphen Chanthasit  2021

 

-Cavin, L.; Deesri, U.; Veran, M.; Khentavong, B.; Jintasakul, P.; Chanthasit, P.; Allain, R. (2019). "A new Lepisosteiformes (Actinopterygii: Ginglymodi) from the Early Cretaceous of Laos and Thailand, SE Asia". Journal of Systematic Palaeontology. 17 (5): 393–407. doi:10.1080/14772019.2018.1426060

 

-A Catalogue of Material and Review of the  Spinosauridae  
Tor Bertin 2010

 

-Allain, Ronan (2014). "New material of the theropod Ichthyovenator from Ban Kalum type locality (Laos): Implications for the synonymy of Spinosaurus and Sigilmassasaurus and the phylogeny of Spinosauridae". Journal of Vertebrate Paleontology Programs and Abstracts. 74: 78

 

@Guns

[Troodon]

New paper

Spinosaurid teeth from the early cretaceous of the Napai Basin Guangxi, China.   Only one of these teeth fall within the rance of Morph Types II Siamosaurus from the Khok Kruat Formation.

Paper suggests a close affinity of the Napai Basin and northeastern Thailand

 

CH between 31 and 36 mm.  Vertical ridges one 12-13 others 14-15 each side

 

 

 

JI Shu'an, ZHANG Pei, LU Daolin. 2022. New materials of the Early Cretaceous spinosaurid (Theropoda) teeth of Napai Basin, Fusui County, Guangxi. Geological Bulletin of China, 41(9): 1509-1515. doi: 10.12097/j.issn.1671-2552.2022.09.001

[Guns]

Very informative post Frank !

 

Just wanna add something up from my own observation . I notice that there are currently 4 type of different type of enamel details present in Laos spinosaurid teeth . So i think it could be more than 2 or even 3 others spinosaurid sp. present in this formation apart from Ichthyovenator sp.  

 

** sorry for a blur photo maybe its time to invest in new digital microscope to replace my old one   

 

cheers

Guns

 

[Guns]

There are also a few interesting teeth

 

- no idea on ID , might be another spinosaurid who know . **Note : visible serrations ( the only 1 of 2 possible serrated spinosaurid teeth that i notice of ) 

 

- Laos shark teeth and fin spine section 

 

- fish teeth 

[Troodon]

33 minutes ago, Guns said:

Just wanna add something up from my own observation . I notice that there are currently 4 type of different type of enamel details present in Laos spinosaurid teeth . So i think it could be more than 2 or even 3 others spinosaurid sp. present in this formation apart from Ichthyovenator sp.  

 

Thanks for the photos and info.. greatly appreciated and a good observation

 

Interesting,  hard to say because we have not seen any evidence of more than two Spinosaurids in any fauna.  What we have seen in Morocco is that Spinosaurid teeth do vary in morphology with some having a no vertical ridges to others have them on one or both sides.   Some also have small denticles.  Might be just animal to animal variation or positional.

 

I wonder if there have been enough research or exploration to really understand what going on since I'm betting the sampling size is small.    Suggest you keep picking up all you can we need lots of data 

 

Really odd tooth but super cool.

 

 

[rocket]

thanks for this interesting informations about age and size of the Thailand/Laos-Spinosauridae. Do not come up often on the market and normally without any informations about site and age... This will really help, thanks

[Guns]

7 hours ago, rocket said:

normally without any informations about site and age...

We always put info about age and locality of those teeth. 

 

Best Regards

Guns

 

 

 

[rocket]

9 hours ago, Guns said:

We always put info about age and locality of those teeth. 

 

Best Regards

Guns

 

 

 

 

great to hear, do not know you as a seller. We have seen them on some platforms but never bought. 

Edited October 18, 2022 by rocket

[Kikokuryu]

On 10/4/2022 at 10:06 AM, Troodon said:

-KEY: Morph type I from above considered Ichthyovenator laosensis   (Manitkoon et al 2022)

@Troodon So if I'm understanding this correctly, Icthyovenator-type teeth need to have a ridge total (both sides combined) of between 42-64 while 22-32 ridges is indet. or cf. Siamosaurus sp. But it also has to have smooth enamel to be Ichty?

 

Some fall outside of the range, but in this group, the left 6 teeth and bottom 2 (serrated) teeth are indet. or Siamosaurus-type, while the only one that could possibly be Ichtyovenator would be the 44 ridge tooth? It may be sample bias, but it seems most teeth from Laos have between 22-32 ridges.

[Troodon]

@KikokuryuYes to your question but smooth crown and wrinkled base Wongos paper

I took another look at the paper and Manitkoon comments

"The teeth of Khok Kruat spinosaurids can be categorized  into two morphotypes (Wongko et al. 2019) and indicate  that two distinct spinosaurid taxa potentially occur in  the Albian-Aptian of Thailand. If these morphotypes are  not related to differences between taxa, they are due to  dimorphism within a single species. However, there are  evidences of several spinosaurid taxa in the same area  from many formations."

 

So we really don't know how may Spinosaurids are in Laos and since the holotype did not have teeth and most may not be Ichthyovenator.   Have no clue how accurate the range indicated in the paper is but 44 appears to be morphotype 1.  Not sure about texture and how important that is in the ID.