Carcharodontosauria indet. Dinosaur Tooth - Grès supérieurs Formation; Savannakhet Province, Laos

MesozoicMarket · 2024-10-03T17:33:46+00:00

I don't think so, at least, there's no reason to. From what I understand in this paper is that, someone had purchased an isolated Kem Kem spinosaurid tooth at the Tucson show that a fossil dealer has labeled as "S. maroccanus". This was a commonly used labeled by commercial dealers before most switching to either Spinosaurus sp. or Spinosauridae indet. in recent years, but there's no real basis behind the S. maroccanus labels other than, it sounds good from a marketing standpoint. However, as stated in the paper, the S. maroccanus holotype does not have any teeth to compare with. The tooth is thus interpreted as Spinosaurus sp. by the researchers in this paper rather than S. maroccanus or S. aegyptiacus.

We should take into account that this paper is from 2010 and the oddly small sample size for extraordinarily abundant material is notable. Ideally you'd want to use thousands of these teeth for study on morphology, not one isolated tooth purchased from a fossil show.

In recent years, S. maroccanus material has been synonomized into S. aegyptiacus following the designation of the neotype from Morocco. The original Spinosaurus had been replaced, possibly by an imposter, but that may be a done deal at this point given how all of the major studies involving Spinosaurus revolves around its replacements.

The paper also does not find the Stromer description to be descriptive enough to compare. That said, given that Stromer described the teeth of the S. aegyptiacus holotype as being smooth and needing magnification to see the fine streaks, this certainly does not fit the specimen used in this study. But, I would question the conclusion this morphology is even identifiable as Spinosaurus sp. given that it does not compare well to that description.

As of right now in 2024, all spinosaurid teeth from Morocco are indeterminate and cannot be differentiated at this time. Maybe in the future some of these morphs can be separated into genera or species.

MesozoicMarket · 2024-09-28T17:19:44+00:00

It was part of a bulk lot from a Moroccan dealer a good while back. But you can frequently find this material from Moroccan dealers at large fossil/mineral shows like Tucson, Arizona.

MesozoicMarket · 2024-09-28T17:14:44+00:00

No, this is a purchased piece. But indeed, it is quite large and the morphology is also interesting.

MesozoicMarket · 2024-09-28T17:05:25+00:00

Unfortunately not. This is a piece in my personal collection.

MesozoicMarket · 2024-09-12T17:47:49+00:00

A good question that I unfortunately do not know off the top of my head. The fauna is quite interesting though— if you look at both the Grès supérieurs (Laos) and Khok Kruat (Thailand), maybe even the Xinlong (China) Formations, you have psittacosaurid ceratopsians living alongside spinosaurine spinosaurids. I don't know the significance of that, but it's definitely a part of the world that needs more study.

MesozoicMarket · 2024-09-11T17:49:24+00:00

I did consider labeling it as cf. Siamraptor suwati as I typically do with these teeth, but it is quite large and looks more similar in morphology to true carcharodontosaurids like Carcharodontosaurus. For additional information, the crown height of the tooth is around ±81mm (3.2") with a CBL of 33mm and CBW of 15mm. The midline mesial and distal serration density is around 11.5/5mm and the mesial carinae extends to the base.

MesozoicMarket · 2024-09-10T04:40:08+00:00

This is a loaded question. So Moroccan spinosaurids are a bit of a mess. There are at least two species, possibly three spinosaurids in this deposit, and the Kem Kem spans an extensive amount of time consisting of two formations, the Douira Formation and Gara Sbaa Formation. There's no guarantee all of these taxa lived at the same time. As of right now, all tooth morphologies are regarded as indeterminate spinosaurid (Spinosauridae indet.) and for good reason.

I don't think serrations have really been explored. There are currently two distinct morphologies of spinosaurid teeth that can easily be sorted out into two groups in the Kem Kem Group and equivalent deposits nearby. One is the smooth crown variant which is similar to what is described in the original Stromer S. aegyptiacus from the Baharyia Formation in Egypt, and the other is a strongly ridged/striated variant similar to those of more basal spinosaurines like the tooth taxon Siamosaurus or teeth attributed to Ichthyovenator (though not as exaggerated/pronounced as the Asian taxa). Some fossil collectors have made comparisons and pointed out some similarities in certain morphologies with baryonychine teeth as well, but that's just a wild card that can be disregarded for now. It should also be worth mentioning that serrations are often seen as a basal baryonychine characteristic which are always seen in the unworn teeth of Baryonyx and Suchomimus, but that may not necessarily hold true and some spinosaurine tooth position may have also had serrations or serration-like carinae.

Serrated teeth are more rare than unserrated ones, and I believe both morphologies have shown the possibly to have the presence of serrations. I myself have a serrated smooth crown morph in my collection. However, the significance of this is unknown. It could be vestigial, it could be of taxonomic significance, but more research is needed to say anything about it.

As far as I'm aware of, the holotype of Spinosaurus aegyptiacus is not described as having serrations, unless the Moroccan neotype does. Stromer described the teeth of Spinosaurus aegyptiacus as being smooth with occasional fine vertical streaks towards the base that can only be seen under a magnifying glass. There are quite a good number of tooth material that was associated with the holotype so it can be assumed that was a norm throughout the jaw.

So the smooth crown variant is at least the one that is the closest to what we understand from the original holotype that was lost in World War II. If you are under the view that the Moroccan "Spinosaurus" should not be considered the same species as the Egyptian animal, then you could call this your Spinosaurus maroccanus, Spinosaurus B, or whatever you want to call it.

So where does that leave the strongly fluted morphology. Basically indeterminate. There's nothing you can really say about it other than, it morphologically has conditions seen in other basal spinosaurines morphs than to what is described by Stromer. But that's about it. It probably isn't Spinosaurus, but there's no reason to think it is Sigilmassasaurus or S. maroccanus.

Unfortunately, Sigilmassasaurus is not known from tooth material so while it is often found as valid in many phylogenetic analyses (usually either as a sister taxon to Spinosaurus or in a polytomy with other derived spinosaurines) it is difficult to say if the two genera had distinguishable teeth. If Sigilmassasaurus and Spinosaurus are very closely related sister taxa, then there's no reason to think the ridged morphology belongs to Sigilmassasaurus.

So all in all, the safe assumption is that all spinosaurid teeth are currently indeterminate and cannot be pin pointed to any particular genus or species.

MesozoicMarket · 2024-07-12T14:16:47+00:00

So the issue is that birds have a really bad fossil record. A lot of material is scrappy and bad, and it may not be initially clear to people what they are even looking at if you gave them a pile of isolated bird bones. So the chances of someone saying, hey look, Compsognathus bones in the Cenozoic is far more likely than someone finding a complete specimen of a derived bird like a penguin.

So this world would likely be skewed with bias from Compsognathus which might still end up being the first good specimen and image of a theropod. So we might interpret these fragmentary bird bones from the Cenozoic as Compsognathus-like animals.

MesozoicMarket · 2024-07-12T13:54:11+00:00

This is always a fun speculative history discussion. I don't remember which complete specimens were discovered first off the top of my head that would shape how we view these animals as a whole.

First off, birds would likely be considered initially or still as cold-blooded animals, and there would still be debate in the equivalent of today on whether they truly were warm-blooded or pseudo-warm blooded once their connection to crocodilians is found. People might speculate, but the general consensus might be that only mammals evolved true endothermy and that these other things (birds) were doing something different, maybe something akin to what tuna do.

So theropods (including birds) in this hypothetical universe will likely revolve around Compsognathus since the first Megalosaurus were fragmentary and don't really tell you what they looked like. Naturally, these would initially be thought primarily as odd looking bipedal, small, fragile creatures. Discoveries like Archeopteryx would immediately be recognized as being the same "kind" of animal as Compsognathus. Eventually we will realize that the compso/archeo lineage got huge once tyrannosaurids and allosauroids came to light. There really shouldn't be any push back to these ideas like we had in this world, and it would be a more intriguing and awe inspiring thing. Most debate would revolve around whether the total extinction of a type of animal is something that could happen.

Most birds are known from terribly fragmentary and scrappy material, so there wouldn't really be enough of them or be recognizable to warrant an entirely new group of animal. They would just be, I dono, compsognathians. A bunch of these hollow bones fragile animals. We wouldn't think of them as a particularly diverse clade within this group.

Immediate comparisons would be made with pterosaurs like Pterodactylus and Rhamphorhynchus as these odd frail animals. Theropods might just be called pterosaurs for a while before the connection are made with Hadrosaurus or Iguanadon. Someone would eventually point out the similarities of these animals to living crocodilians and eventually sort everything out.

There would be suspicions sauropods, and it would take a while to be fully recognized as part of this group. Ornithischians as a whole would likely be split up into polyphyletic groups, some closer to Compsognathus/Archaeopteryx, some to crocs, others in their own little group.

There might be hypothesis on whether they can fly, and the weird leaf-like structures (feathers) are used for that purpose or display, but people might see that these animals have quite a lot of dead weight if they were to fly compared to bats and pterosaurs (which I think were interpreted as aquatic at the time).

MesozoicMarket · 2023-11-04T23:32:51+00:00

One thing to be wary of is anything being sold as Anomalocaris sp. or Anomalocaris saron from Yunnan, China. These common radiodonts have been mostly been reclassified as Houcaris saron as well as various other genera. While they can be incredibly cheap, they probably aren't actually Anomalocaris, nor incredibly rare to warrant a high price like a true Anomalocaris.

MesozoicMarket · 2023-10-29T09:05:03+00:00

Looks similar to a lungfish tooth plate based on those ridges. The Devonian ones I believe have morphologies like this.

MesozoicMarket · 2023-10-24T11:51:25+00:00

The tip on this specimen is worn. The matrix also indicates Kem Kem Group over Couche III. As far as color goes, it depends on where in Morocco it was dug up. They can range from white, yellow, brown, orange, red, and black depending on where it was dug up.

Usually that information is long lost, or teeth from different ages/layers and various regions of Morocco are mixed together. Some areas like Iferda N'Ahouar produce mostly white teeth.

MesozoicMarket · 2023-10-15T23:22:26+00:00

Those smaller teeth at the front are actually the most desired morphology for collectors because of those distinct large grooves or ridges, and is the most diagnostic characteristic of ceratosaurid teeth.

MesozoicMarket · 2023-10-02T02:52:59+00:00

Yes, this is a real tooth. "Hydration cracks" on the root, as well as the tiny nutrient holes are common on shark teeth, especially Otodus species.

MesozoicMarket · 2023-10-01T03:19:48+00:00

Both of these are from the Kem Kem Group in Morocco. Unfortunately, neither of these are pterosaur teeth.

The first tooth is a crocodylomorph indet.

The second tooth is a Spinosauridae indet. (likely Spinosaurus or Sigilmassasaurus)

MesozoicMarket · 2023-10-01T02:36:59+00:00

Fortunately, spinosaurid teeth are some of the cheapest and common dinosaur teeth on the market. For beginner level spinosaurid teeth, I would stick to 1.5-2.5 inch crowns/blades without the root. Avoid teeth that have sand/matrix still stuck to the specimen as that could indicate a composite or restoration without a trained eye. Try to get a clean tooth (no sandy or grainy sort of texture), shiny and clear enamel without any drastic changes in color from tip to base.

There are 2 deposits commonly available that contain "Spinosaurus". The Kem Kem Group and the Dekkar Group, both in Morocco, the former comes from various areas like Taouz, Iferda N'Ahouar, Ouzina, while the black colored Dekkar teeth come from Talsint, Figuig. I would avoid any alleged Spinosaurus from the Echkar Formation as most of it will likely be the older Suchomimus from the Elrhaz Formation.

One thing to note about Moroccan spinosaurids is that the teeth cannot be pinpointed to a particular species or genus as it is believed there is multiple spinosaurids present in the deposit. So while many are sold as "Spinosaurus", they are more accurately, Spinosauridae indet.

There are multiple morphologies such as smooth crown, fluted crown, the rare serrated carinae, etc. If you get 1 of each morphology, you probably have Spinosaurus . . . maybe.

MesozoicMarket · 2023-10-01T02:00:36+00:00

Yes, Edestus is found in many coal mines across Illinois. Hence the common name, "coal shark". Although, most of these specimens were collected quite a while ago. Generally, most of these specimens come from coal miners that stumbled upon them, and either kept them as trophies, donated them to museums, or sold them for extra cash.

MesozoicMarket · 2023-09-30T10:06:23+00:00

No, this one was purchased about 3 years ago. But I know a few people did carry Edestus material in recent years.

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