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Occasionally we see dinosaur material from Portugal for sale, mostly theropod teeth, but I post this because the dinosaurs of the Lourinhã Group are very interesting to those of us that are familiar with the Morrison Formation.  Information here may help us identify teeth from the Morisson

 

From an abstract: The Lourinhã and Alcobaça formations (in Portugal), Morrison Formation (in North America) an Tendaguru Beds (in Tanzania) can be compared. These three Late Jurassic areas, dated as Kimmeridgian to Tithonian are similar paleoenvironmentally and faunally. Four dinosaur genera are shared between Portugal and the Morrison (Allosaurus, Torvosaurus, Ceratosaurus and Apatosaurus), as well as all non-avian dinosaur families. 

Late Jurassic Map

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Portugal has a high diversity of dinosaurs. 

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The Lourinhã Formation is the most notable unit of the group not only noted for teeth & bones but eggs and trackways.   The Alcobaça Formation is also included in the group.  

 

Here is a geologic look at westcentral Portugal.

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The coastline is absolutly beautiful and a challenge to collect.   Teeth, tracks and bones are typically found in the boulders making extraction a nightmare.

 

00-Serra do Bouro-Caldas da Rainha.jpg05.jpg07.jpg

 

2016-07-19 10.25.53.jpg

 

 

 

 

 

Lourhina Fm.pdf

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Edited 11/20/17

 

The large theropods of this region are poorly understood but with new discoveries a clearer picture is beginning to form.

 

Isolated theropod teeth are abundant in this coastline however reliable identification of these teeth is complex since many morphotypes exist in poorly represented groups. 

 

Current understanding shows the presence of several groups such as Torvosaurus, Ceratosaurus and Allosaurus and morphotypes belonging to Megalosauroid, Allosauroid, Tyrannosauroid, Dromaeosaurid, and Richardoestesia.  Marshosaurus may also be present.

So you can understand why its difficult to ID a tooth to a species.

 

 

Torvosaurus gurneyi ;  Megalosaurid indet

 

T. gurneyi is the largest theropod in Europe is known from a maxilla.  It's similar to its cousin in the Morrison T. tanneri but appears to be larger.  

 

Identification:  (a number of morphtypes exist making ID confusing)

-Serration Density: both Carinae have an average of 7.5 denticles per 5 mm midline

-Mesial denticles are short with rounded or flat ends.

-Distal denticles are subquadrangular with rounded ends perpendicular to the carinae

-Most have transverse undulations

 

Torvo.jpg.1120e85f0758c1f731a4e3f88c8c5ff6.jpg

 

 

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Megalosaurid indet  ( Marshosaurus ? )

 

Identification:

-Density: Mesial denticles around 15, Distal denticles 20 per 5mm   (all midline)

-Distal Carina extends down slightly below the cervix

-Mesial Carina extends down to midline

 

Marsh1.jpg.b1799afdbe0fd64c193abc56ca715892.jpg

 

 

Ceratosaurus dentisulcatus; Ceratosaurus sp

 

C. dentisulcatus is a species that is still uncertain, very close to the Morrison's C. nasicornis, will require additional discoveries to confirm if it's a valid taxo 

 

Identification:  Premaxillary and Mesial Dentary

-Vertical grooves and ridges on the lingual side of crowns 

-Mesial denticles are much smaller than distal ones

-Density: Mesial denticles 19 per 5 mm, Distal denticles 11 per 5mm   (all midline)

 

5a12ceb96b9fa_CertoPremax1b.jpg.00ce1ddc41138c71bda2195da5305559.jpg

 

Identification : Maxillary and Dentary Teeth

-Mesial denticles are short and different than distal one

-Density:  both Carinae have an average of 14 denticles per 5mm midline

-Very compressed crown

-Carinae extends down to the cervix and are usually parallel

 

CertoDentary1.jpg.5aa8ffe42bccceaa2e6f97d162b269a5.jpg

 

 

Allosaurus europaeus ? Allosaurid, Allosaurid sp.

Similiar to Allosauruids in the Morrison.  However with A. europaeus only the back end of the skull was found with only the very posterior tooth so the morphology of the teeth are unknown.

 

Identification:

-Density: Mesial denticles Average 12, Distal denticles Average 16.8 per 5mm   (all midline)

-Mesial carina extends more than two thirds of the crown height.

-Mesial carina is centrally located but the distal shows a labial displacement

-Denticles are different on both carinae

 

Allo.jpg.1f48792cfa6da2942d79c858d602f76a.jpg

 

Allosaurid indet.

 

-Density: Both Carinae have about 12 denticles per 5 mm (midline)

-Mesial carina ends approximately at midline of the crown height but can extend to cervix.

-Crowns are slightly recurved

-Mesial denticles are smaller toward the tip than midline

 

allo2.thumb.jpg.753fb189a342041dcf1b5e61d7cbb8bd.jpg

 

 

 

Lourinhanosaurus antunesi 

Was described in 1998 as an Allosauruid but it's uncertain what the family it fits into, current thinking by some place it as an Megalosauroid.   No skull material was found in the holotype so the morphology of its teeth is unknown

 

Identification is unknown

 

 

Abelsaurid indet.

In 2014 an isolated Abelisaurid tooth was discovered on the cliffs off of Lourinhã.   Additional discoveries will be needed to described this dinosaur.  Picture of that that tooth and another is shown.

 

Screenshot_20161011-061142.jpgScreenshot_20161011-061109.jpg

 

cf Richardoestesia

 

Other theropods material has been found like the following tooth initially identified as cf Richardoestesia  but new discoveries will get needed to properly describe it.

- Serration Density - 4 and 5 denticles per mm on both carinae.

 

20161011_061309.png

 

Reference Sources:

Hendrickx, C., & Mateus O. (2014).  Abelisauridae (Dinosauria: Theropoda) from the Late Jurassic of Portugal and dentition-based phylogeny as a contribution for the identification of isolated theropod teeth. Zootaxa. 3759, 1-74.

 

Mateus, O., Walen A., & Antunes M. T. (2006).  The large theropod fauna of the Lourinhã Formation (Portugal) and its similarity to the Morrison Formation, with a description of a new species of Allosaurus. New Mexico Museum of Natural History and Science Bulletin. 36, 123-129

 

 Malafaia,E., Escaso, F. et al (2017) Analysis of diversity and geographical distribution of isolated theropod teeth from upper Jurassic of the Lusitanian Basen,  Portugal 

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Herbivores are present:

Ornithopods are present described mostly through bones: Draconyx loureiroi (cousin to Camptosaurus) see the last figure5 below item  "C" .  Dryosaurus, Hypsilophodon and Phyllodon.

 

Sauropods are also represented in this fauna but not fully understood.

Zby atlanticus

Screenshot_20161011-062950.jpg

 

 

 

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Very nice and informative topic Troodon:fistbump:...I've to confess I know almost nothing about Portuguese dinosaurs:blush:.

Lourinhã's formation produces some very nice and big bivalves, however there are some spots where fossil collecting is not allowed (I think ).

 

Regards,

 

 

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Good stuff as always.

 

It's easy to forget that Europe was so close to America at the time. Makes a lot of sense that there were similar animals on both sides of the pond.

Olof Moleman AKA Lord Trilobite

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On 10/11/2016 at 1:48 PM, HamptonsDoc said:

Thanks for the info! Do you have anymore info on the eggs from the area?

 

I'm not aware of what egg material has been found other than crushed eggs and embryonic material.  

Sorry nothing available in the open market...:(

 

Paper on what I mentioned.  Very technical :(

http://www.nature.com/articles/srep01924

 

 

Screenshot_20161019-123502.jpg

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Awesome and very informative post!  Thanks so much for sharing!  I will no longer complain about digging in heavy clay! :)

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Fantastic post Troodon

 

It´s very interesting to see this information about the dinossaurs of my country :)

 

Very quality in the pictures and information.

 

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I envy the people that are able to hunt here! Not only are the fossils there very unique and cool, but it's also a very pretty location and a nice collecting site. Thanks for sharing Troodon.

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Trying to ID teeth from this region can be difficult.  The paper I posted of northern German theropods teeth can be helpful since the families and age overlap.

 

 

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  • 4 months later...

Yea, it seems hard identifying these fossils. Any ideas about these 3 Portugal Louhrinã teeth? Any ideas would be appreciated. Thanx in advanve!

 

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"That belongs in a museum!"

- Indiana Jones

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Very difficult to tell much from just tips.  You need to see the shape of the crown, serration count and where they are in the carinae to aid in the diagnosis.  Sharper pictures,  and closer images of your third tooth might help with an ID.  Small teeth are very hard to ID not a lot diagnostic about them especially if they are premaxillary teeth.

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Thanx Troodon. 

My mate is in the process of taking some photos under a lens. She isn't the best at taking photos...

However, on the first two teeth the serrations count is 26 and 27 per cm. I do believe the third has 4 serrations along the length.

"That belongs in a museum!"

- Indiana Jones

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Is it legal to collect fossils in Portugal.  And export?  I ask as a guy who likes to go to Europe every now and then....

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9 hours ago, ElToro said:

Thanx Troodon. 

My mate is in the process of taking some photos under a lens. She isn't the best at taking photos...

However, on the first two teeth the serrations count is 26 and 27 per cm. I do believe the third has 4 serrations along the length.

Serration count needs to be taken at midline but like I said without the rest of the tooth is difficult to diagnose.  That third tooth looks like a Premax but is hard to tell from the photos.  If it is they all look the same and there is nothing diagnostic about them.

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9 hours ago, jpc said:

Is it legal to collect fossils in Portugal.  And export?  I ask as a guy who likes to go to Europe every now and then....

I don't think so but it is definitely the case in Spain.

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It is illegal to export fossils from Spain, but generally specific laws are only applied to dinosaur remains. Same case for Portugal (and authorities are very sensitive to this topic there, from my own experience with older scientific collections incuding single dinosaur bones and teeth, but also with "new" material). Even collecting such material in strata known for dinosaur material is problematic there and can cause in uncomfortable situations for collectors.

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  • 8 months later...

I've updated the theropod section, second page, to provide more detailed information to help in tooth identification.  Isolated teeth from this fauna are very difficult and complex to identify and may be impossible to get down to a species level.  The theropod diversity in this fauna is large and poorly understood.

 Partial teeth or those that do not have reasonably complete serrations on both carinae will be extremely difficult to diagnose. 

 

I post this information since it's interesting and the fauna associated with the Lourinha Formation formation is very similar to that of the Morrison Formation.  This information should be useful in identifying those teeth or at least getting close since so little is published from the Jurassic of North America.

 

 

 

 

 

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Thank you very much for this very informative post. Now I would like to go there for my next vacations ;)

Have you been to these cliffs by yourself ? Do you know how hard is it to find and to excavate the fossils ?

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49 minutes ago, Pixpaleosky said:

Thank you very much for this very informative post. Now I would like to go there for my next vacations ;)

Have you been to these cliffs by yourself ? Do you know how hard is it to find and to excavate the fossils ?

No I never collected in this area.  It's my understanding that collecting is not easy, the cliffs are dangerous and lot of the finds are encased in boulders that require extraction tools.

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  • 5 months later...

Frank, 

Which paper has these specific illustration in it? I didn’t see these in the three papers you cited.

Thanks.

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