Were There European Oviraptorosaurs?


You may have heard of this in a few sites recently, most notably at Darren Naish’s Tetrapod Zoology. If you haven’t, check it out along with Matt Martynuik’s take on what kind of animal Darren is talking about, which is represented by a single vertebra. Darren’s joke, about how the material he describes is often very fragmentary or isolated bits, is telling, as much of what comes from the Wealden beds of England (an extension of the Wealden Supergroup of northern Europe) is comprised of this type of stuff. Nonetheless, there have been conclusions made (much of it by Darren himself) in the literature that bear note. This is predominantly based on the argument that there might be oviraptorosaurs in England, while there may also have been other derived groups of paravians and other maniraptorans all over Europe.

BEXHM 2008.14.1, a posterior cervical from the Ashdown Beds of the Wealden, Wadhurst Clay Formation, of England, near Hastings in eastern East Sussex. A, dorsal, B, anterior, C, left lateral, D, posterior, E, right lateral, F, ventral. Abbreviations: f, lateral neurocentral and central fossae, hy, hypapophysis, pp, parapophysis. Scale bar is true for all vertebrae.

A note to the image above: The vertebrae are modified from Naish and Sweetman (2011) and arranged so that each adjacent vertebra is 90 degrees to the others. As modified, grey areas indicate missing material and possible outlines of the regions. Because of the angles by which the vertebra was photographed, various views are not perfectly aligned with one another, and some are a-tilt.

So, that’s a beautiful vertebra, huh? BEXHM 2008.14.1 is very small, as Darren notes. It’s also partially eroded, so that the rims of the centrum, both cranial and caudal, are missing and the cancellous internal structure exposed; this is also true for the hypapophysis and the neural spine, while one of the prezygapophyses is broken at the base, exposing fairly large internal camarae. Darren’s pretty up to speed on his comparisons, so much of what he notes in the paper with Steve Sweetman is spot on. The only thing that brings this to my attention is that in his blog, Darren makes obvious references to his opinion on possible oviraptorosaurian affinities for the material. This is in the paper, but in much muted form.

English Oviraptorosaurs?

This argument goes back a bit, to where Darren and Dave Martill (2002) had previously made the argument for Thecocoelurus daviesi (von Huene, 1923) based on another cervical vertebra (NHMUK R181) from the Wessex Formation of the Isle of Wight, albeit larger but cut in half and in even worse conditions of preservation as much of the surface is damaged. Several other small theropod bits have been named from the Early Cretaceous beds of England, but none of these have been implicated as potential oviraptorosaurs, so I won’t cover them here. Naish (2002) covered the complicated history of Aristosuchus pusillus (Owen, 1876, see Seeley, 1887), Calamosaurus foxii (von Huene, 1923, following Fox, 1866) and Calamospondylus oweni (Fox, 1866). Plus there’s a tibia in there somewhere, and more bits and pieces that today wouldn’t receive new names, despite being isolated vertebrae and the majority of such bearing unique binomial nomenclature nowadays.

It should first be noted that there are no features of the cervical vertebrae that are diagnostic to the Oviraptorosauria as a clade [n1], and Naish and Sweetman (2011) were unable to find any feature that could more firmly attach the vertebra in theropods than as a maniraptoran. When cervical vertebrae are so characterized, it is in the general (take, for example, Osmólska et al., 2004). For example, all cervical vertebrae are platycoelous, with only a slight cranial cupping; they are always pneumatized with an external foramen on the centrum (which is sometimes doubled); there are distinct epipophyses on even posterior cervicals, and although they are not quadrangular, they are still apparent; the hypapophysis is anteriorly situated on the centrum, rather than central along its length, and there are between two and four, localized to the anterior dorsals and extending into the ultimate or up to the penultimate cervical.

Naish and Martill (2002) had previously also argued that Thecocoelurus daviesi was also an oviraptorosaur, compared to caenagnathids specifically, due in part to the ventral transverse concavity of the centrum, development of elongated ventral ridges along the ventrolateral margins of the centrum (and consequently giving the vertebra a square aspect in section), and the ventral “hourglass” shape of the centrum in ventral view. This was supported by a brief phylogenetic analysis based on the work of Frankfurt and Chiappe (1999) who had previously included several so-called Argentinian oviraptorosaur specimens (from the Maastrichtian Lecho Formation); this analysis supported the inclusion of Thecocoelurus daviesi and MCN-PV 622, a mid-cervical vertebra (the “El Brete theropod”), as members of Oviraptorosauria on the basis of sevral “uinambiguous” characteristics, including those previously mentioned.

Cervical vertebrae of proposed oviraptorosaurs. A, MACN-PV 622, the El Brete “oviraptorosaur,” in 1, dorsal, 2, left lateral, 3, cranial and 4, ventral views. B, Thecocoelurus daviesi (Seeley, 1888), holotype NHMUK R901, in 1, slightly cranial dorsal, 2, right lateral, 3, cranial, 4, ventral and 5 left lateral views. Scale bar in A equals 1 cm, in B 2 cm. A after Agnolin and Martinalli (2007), B after Naish and Martill (2002).

But what Makes an Oviraptorosaur?

Naish and Sweetman (2011) note a single feature that they ascribe particularly with oviraptorosaurs:

The X-like shape of the neural arch evident in dorsal view (Fig. 4E) recalls that seen in some oviraptorosaurian maniraptorans (Makovicky and Sues, 1998; He et al., 2008)[.] [pg. 468]

However, Darren is more particular on his blog:

On first seeing the vertebra, I was stuck by the X-like shape of the neural arch (as seen in dorsal view), the large hypapophysis (a prominent keel located on the midline of the ventral surface) and the presence of fossae on the sides of the neural arch. It looked immediately like a maniraptoran cervical vertebra, especially that of an oviraptorosaur. This was confirmed by other details, like the shapes of the articular surfaces, the positions of the parapophyses, the shapes of the zygapophyses and so on.

So in this manner, we are closer to the more particular features that are oviraptorosaurian-like, especially the development of large, anteriorly-placed hypaophyses in the cervicodorsal transition series, and “X“-shaped neural arches. What do these things mean, and are they even relevant?

1. “X”-shaped Vertebrae

Darren writes:

The X-like shape of the neural arch gives the vertebra an oviraptorosaur-like appearance, and various other features are consistent with such an identification. Meanwhile, the proportionally large neural canal makes it bird-like. As we argue in the paper, however, the proportionally large neural canal seen in birds may be a size-related feature rather than a specific character of Avialae. For now, it seems most prudent to identify the specimen as Maniraptora indet., though I do suspect that it’s from an oviraptorosaur or oviraptorosaur-like taxon.

First thing’s first — what’s an “X“-shaped vertebra? There are multiple answers to this question. This was a feature originally used to help define Therizinosauroidea by Russell and Dong (1994); this feature was then used by Makovicky and Sues (1998), where they wrote:

39. Cervical neural spines anteroposteriorly long (0) or short and centered on neural arch, so that arch is X-shaped in dorsal view (1) (Makovicky, 1995).

Makovicky (1995) also used spine height as a criterion, but seem to have dropped it. Russell and Dong (1994) and Makovicky and Sues (1998) were a bit off in their coding of this character, as they use it specifically when dealing with oviraptorosaurs. The latter in particular used it to help place Microvenator celer into Oviraptorosauria. While I do not disagree, it should be noted that the character is fairly ambiguous on what it intends to accomplish, and how it can be qualified. As written, it refers to two qualities: neural spine length (where the anterior end of the spine is in the middle of the vertebra, at least) and position. Centralization means more anterior, while short would seem to be more easily quantifiable elsewhere. This character is not quantified here, nor has it been elsewhere. For example, how short is “short,” and how close to “center” does it need to be? I may have a suggestion on this, but it bears some issues.

Posterior cervical vertebrae of several theropods illustrating the nature of “X”-shaped vertebrae in dorsal view. A, BEXHM 2008.14.1, the Ashdown maniraptoran; B, Microvenator celer (Ostrom, 1970), holotype AMNH 3041; C, Nomingia gobiensis (Barsbold et al., 2000), holotype MPC-D 100/119; D, Noasaurus leali (Bonbaparte and Powell, 1980), holotype PVL 4061. 1 shows the mean long axial array of the zygapophyses towards the midline, and 2 shows the axes in isolation. Vertebrae are not to scale. A after Naish and Sweetman (2011), B after Makovicky & Sues (1998), C after Barsbold et al. (2000), and D after Agnolin and Martinelli (2008).

Here I have illustrated the Ashdown vertebra and two oviraptorosaurs and an abelisauroid, where the position of the neural spine (based on the illustration) is localized along with four main axes, representing the mean of each zygapophyses. A secondary set of lines shows the direct point-to-point form of an “X” overlaying the axes, with the position of the neural spine indicated. To illustrate a problem, note that the “X” crosses the neural-spine position in two of the taxa shown, but not the others. All vertebrae shown are posterior cervicals, but it should be noted that their exact position is likely to vary due to incomplete material, and moreover, variation in the vertebral series alters the length of the spines and sometimes inconsistently. An additional problem includes how the vertebra is oriented to measure the “X” and its relevance to the neural spine.

As above in C, the misplacement of the “X” to the spine is based on a slight rotation of the vertebral series, while in B, shifting the neural arch slightly will result in moving the “X” out of the spine. Is this consistent? I don’t think so. Moreover, it’s not restricted to oviraptorosaurs, as any cervical vertebra with a neural spine located close to the midline in lateral view, even by a smidge, will produce this effect. This is thus true for various allosauroids, tyrannosauroids, ornithomimosaurs, alvarezsaurids, etc. Virtually the host of Tetanurae have “X“-shaped cervicals in dorsal view, and thus I do not think there is any reason to assume this feature has value diagnosing oviraptorosaurs in the specific.

With the inclusion of Noasaurus leali, an abelisauroid with particularly “avian” vertebrae, it becomes clear that “X“-shape is not a typical oviraptorosaurian feature; it matters only where the neural spine is positioned on the vertebra.

2. Large, Anteriorly-Placed Hypapophyses

What is particularly peculiar is that this feature tends not to be included in phylogenetic analysis, despite description in papers on oviraptorosaurian taxa. It’s presence is not exclusive to oviraptorosaurs, and in fact Naish and Sweetman (2011) note the shape and placement of the hypapophyses are more widely distributed among maniraptorans, noting troodontids especially:

[N]otably, the hypapophyses of some troodontids are highly similar in shape and position to that of the Ashdown cervical (Makovicky and Norell, 2004).

The element in question is below, where you can also see large lateral fossae on the neural arch, generally below the transverse processes, and which are also characteristic of Maniraptoriformes (as you can see below, they exist in troodontids, as they do in dromaeosaurids, and ornithomimosaurs, and tyrannosauroids…).

Troodontid anterior dorsal, after Makovicky and Norell (2004). Referred to Troodon formosus, and likely part of the Two Medicine Formation troodontid collection at the MOR. In ventral and left lateral views. Scale bar equals 1 cm.

But finally, Darren also notes “the shapes of the articular surfaces” and “the shapes of the zygapophyses” , but does not elaborate on this. In the former, I will assume he is talking about the centrum articular surfaces (both anterior and posterior). On the former, however, Naish and Sweetman (2011) note that “[t]he squarish centrum and tall neural arch makes the specimen look rather different from the cervicals of therizinosaurs and caenagnathid oviraptorosaurs, which have elongate, shallow centra and long, lowneural arches.” Of course, Naish and Sweetman were talking about true cervicals, when what we want to look at are cervicodorsals. Most oviraptorosaurs are unobservable on this matter, having been preserved as roadkill specimens and most are thus available only from a crushed side or dorsal view. Of the few specimens we do have in which we can view the vertebrae from an anterior and posterior perspective, there is Microvenator celer Ostrom (1970), Avimimus portentosus Kurzanov (1981) and Nomingia gobiensis (Barsbold et al., 2000). Mickey suggests due to his analyses that various features should place the last two in with the caenagnathids, and I see no reason to disagree with this at the moment.

3. “Shapes of the Articular Surfaces”

In Microvenator celer (using Makovicky and Sues, 1998), virtually all centra are wide than deep (personal observation); anterior cervical, anterior dorsal, and posterior dorsal vertebrae, along with several caudal vertebrae, exhibit extremely wide centra with faces shallower than the width of the neurocentral articulation of the neural arches they are attached to, given Makovicky and Sues (1998)’s abbreviated discussion of the vertebrae. Note that the neural arches and centra are always separated in all vertebrae of AMNH 3041, an indication of general immaturity.

Microvenator celer Ostrom, 1970. AMNH 3041, posterior cervical in left lateral (A,B) and dorsal (C) views, after Makovicky and Sues (1998). Scale bar equals 1 cm.

In Avimimus portentosus at least (using Vickers-Rich et al., 2002, meaning use of PIN 3907/1, the holotype, which preserves a nearly complete dorsal series and partial cervical series), the vertebral centra are almost always taller than wide during the transition between cervical and dorsal, and this is especially significant in all of the vertebrae with hypapophyses. Note the absence of much of the neural arches; in the anterior vertebrae in the sequence, the neural arches are completely fused to the centrum, and there is no indication of a suture; several vertebrae show breakage around the neurocentral suture, including in the anterior cervicals and in the cervicodorsals, and in some dorsals, but this is variable and inconsistent with a fusion regime; the specimen is considered to be mature, and is larger than the animal indicated by the fully fused PIN 3907/3 (the well-known skull). This implies either that the larger specimen is not fully grown, or that cranial and vertebral fusion are not firm indicators in this taxon for skeletal maturity. This is reiterated in the skeleton of LH PV18, holotype of Raptorex kriegsteini, which shows developed fusion of the cranium, partial fusion of the vertebral series (Sereno et al., 2009), and is nearly 6 years old (Tsuihiji et al., 2011), and has thus maintained small subadult size at an age when similar theropods reach much larger sizes.

Avimimus portentosus (Kurzanov, 1981), PIN 3907/1 cervicodorsals. A, sequence of three consecutive vertebrae in left lateral view with large hypapophyses; B, samevertebrae in anterior view; C, same, in posterior view. Black arrows in A indicate pneumatic foramina. “hy” and white arrows points to hypapophyses, largely for the anterior and posterior views. Modified from Vickers-Rich et al., 2002.

In Nomingia gobiensis (using Barsbold et al., 2000), the dimensions of the centra are undescribed and unavailable for examination. The vertebral series, complete including a few posterior cervicals all the way through to the tip of the tail, is generally displayed in full articulation as preserved, and thus the elements have not been separated for examination yet. The neurocentral sutures in the posterior cervicals have not fully closed yet, but are obliterated in the anterior dorsals, and there are pneumatic foramina in all the centra, most of which are indicated by a sharp margin or a small dorsal lamina (as in the first three vertebrae shown below).

Such foramina are present, as I said, in all oviraptorosaurs. They are always present in the cervicodorsals, and are diagnostically present in the dorsal series. This seems to be different in some taxa, for example Similicaudipteryx yixianensis (He et al., 2008), in which the authors note that “[t]he last cervical centrum bears a pair of pleurocoels, which are situated close to the upper portion of the centrum in lateral view.” [pg.180] Even though the figures are grainy and small, I find myself noting that several other vertebrae show features of pleurocoels, including a preceding cervical exposed partially in ventral view, and the succeeding first dorsal. Further cervicals have fused cervical ribs, and are positioned in such a way as to prevent their condition from being known, as these foramina are almost immediately posterior to or dorsal to the parapophyses in all vertebra, where the cervical rib obscures it.

Thus when Darren notes on his blog in reply to a comment I made that “Similicaudipteryx seems to have pneumatic foramina on one vertebra at the base of the neck but not on any of the others” [comment #20], I tend to be wary; nowhere does He et al. note that only one vertebra has them, just by remarking on one vertebra with “a pair.” I am perfectly willing to accept that He et al. mean exactly what Darren implies they do, but I cannot check this given the material at hand.

Nomingia gobiensis (Barsbold et al., 2000), holotype MPC-D 100/119. Anteriormost presacrals in left lateral and dorsal views. Small white arrows indicate hypapophyses, small black arrows indicate pneumatic foramina and (in the neural arches) pneumatic pleurocoels; large white arrow indicates a large epipophysis on the last cervical, and large black arrows indicate un-obliterated neurocentral sutures, which are not apparent on the dorsals. Scale bar equals 10 cm.

4. “Shapes of the Zygapophyses”

Finally, Naish mentions “the shapes of the zygapophyses.” This is an ambiguous statement, but I will assume it means the implication that oviraptorosaurs have dorsally directed prezygapophyses and, almost consequently, a diapophysis on level with the prezygapophysis. It was this latter bit, along with features such as the “U“-shape of the prezygapophyseal lacuna (visible in dorsal view in Microvenator celer above), “pedunculate pneumatic foramina” (there being a raised lip around the foramen, not always present), and the anterior position of the neural spine, a feature that persists in the cervicals and dorsals of some but not all oviraptorosaurs (for example, not in Microvenator celer or Nomingia gobiensis, both above).

These features were used by Agnolin and Martinelli (2007) to determine that MACN-PV 622 (a cervical vertebra from the El Brete exposure of the Late Cretaceous, Maastrichtian Lecho Formation in Argentia, described by Frankfurt and Chiappe {1999} as an oviraptorosaur) was not an oviraptorosaur. Instead, Agnolin and Martinelli (2007) referred this vertebra to the Noasauridae. Naish and Martill (2002) previously noted that Thecocoelurus daviesi had many features in common with oviraptorosaurs, especially noting caenagnathids; Naish and Sweetman (2011) rebut this by noting Agnolin and Martinelli (2007), and implied the material was very reminiscent of abelisauroids, and thus this pretty much impairs NHMUK R901 as an oviraptorosaur as well, although its chances are just as high as it has a pneumatic foramen and a ventral morphology that BEXHM 2008.14.1 lacks.

But there’s that nagging prezygapophyseal shape thingy. If this is what Naish is referring to, the orientation of the prezygapophyses, then there’s some good basis for this in oviraptorosaurs. And in Deinonychus antirrhopus Ostrom, 1969. It’s not exclusive to oviraptorosaurs, but is present in dromaeosaurs as well, which enforces this feature in maniraptorans, rather than to oviraptorosaurs.

Posterior cervical or anterior dorsal vertebrae with the angle of the prezygapophysis in lateral aspect, in left lateral view. A, Deinonychus antirrhopus Ostrom (1969a), YPM 5204, anterior dorsal (Ostrom, 1969b notes this is as anterior as the fourth dorsal). Note the anteriorly-placed hypapophysis and pleurocoel; B, Nomingia gobiensis Barsbold et al. (2000), holotype MPC-D 100/119, posterior cervical; C, Microvenator celer Ostrom (1970), holotype AMNH 3041, posterior cervical vertebra; D, Ashdown maniraptoran, BEXHM 2008.14.1. 1 indicates an overlay of the vertebra with the angle of the prezygapophyses against two axes; 2, the axes and angles isolated. A is after Ostrom (1969b), B modified from Barsbold et al. (2000), C modified from Makovicky and Sues (1997), C after Naish and Sweetman (2011).

Note to the image above: The axes in the figure are drawn after two constraints — first, a horizontal line is drawn from the anterior to the posterior ends of the floor of the neural canal, adjusted with either alignment of the neurocentral suture when it is clearly close to the canal’s margin, or based on the actual ventral margins of the canal in cranial and caudal views, with the vertebra aligned in lateral view to match this (this technique was used with the Ashdown vertebra). I am perfectly aware that this technique is flawed, in that a stable line is frought with problems of finding such a line meaningful when such things have never been established as constant (is there a single stable line in biology from which to draw any angle? I don’t think so). Nonetheless, a chose a line, and this is it.

This technique is further flawed in practice, when vertebrae are not available in anterior or posterior views, but are rather reliant on landmarks such as the neurocentral suture or clear limits to the anterior or posterior articular faces of the centrum. The second line is perpendicular to the first and placed at the cranial limit of the cranial articular face. This line is useful because it allows a second constraint on measuring the angle of the prezygapophyses that relate to the vertebrae in a series, based on how they line up with one another, instead of the vertebra by itself.

Here, dromaeosaurids (and Deinonychus antirrhopus in particular) have a high angle of the prezygapophyses, which continues posteriorly into the dorsal series, as in most theropod taxa; in Nomingia gobiensis, however, this angle is lower, and only gets lower posteriorly; and in Microvenator celer, this anglke remains high until the posterior dorsals where, as in the sacrals, it comes close to horizontal. Nonetheless, this angle is close to 45° in the dromaeosaurid, over 50° in Microvenator celer, but is closer to 40° in Nomingia gobiensis, and is lower in troodontids (see above). In the Ashdown vertebra, this angle is almost higher than the other taxa, lower than in Microvenator celer but higher than in the others. But as might be apparent, this doesn’t necessarily mean much, and they are so close to one another that the differentiation may only be functional, as size and vertebral position can influence this angle. So is this a valuable feature, and does it help us discriminate a clade within Maniraptora? My quick math suggests “No.”

Conclusion

Naish and Sweetman (2011) indicate that their specimen is a skeletally mature animal due to neurocentral fusion, although this indicates very little in terms of actual age. The animal could, in fact, get larger, and the remains are too limited to determine age. Rather, they should suggest that the single vertebra could indicate close to maximal size. Nonetheless, several things should be noted:

  1. X“-shaped vertebrae are spread across the Tetanurae, but an actual discussion of this character would be helpful to clarify how the “X” of the zygapophyses in dorsal view differs from most theropods. It is my understanding that this feature is useless for characterizing Oviraptorosauria.
  2. A pneumatic foramen of the centrum is characteristic of oviraptorosaurs, and is invariable in them; its absence in some vertebrae of some taxa does not diminish this fact. However, this feature varies throughout Maniraptora, and is present many maniraptoran cervical series, including dromaeosaurids.
  3. The development of large anteriorly-placed hypapophyses appears to be another maniraptoran trait, present as it is in troodontids, dromaeosaurids, oviraptorids, and various members of Avialae.
  4. Angle of the prezygapophyses in lateral view, the closest I can come to clarifying any value to “shape of the prezygapophyses,” is unquantified in oviraptorosaurs, and is unquantified in other maniraptorans, thus affirming this feature as an oviraptorosaur apomorphy is problematic. If this refers to the aspect of the prezygapophysis, it’s shape (straight, curved, sigmoid, etc.) then this feature has never been clarified, and would nonetheless vary throughout the series.
  5. BEXHM 2008.14.1 lacks other purported oviraptorosaur apomorphies, including a pneumatic foramen, the pedunculate form of said foramen, an anteriorly-placed neural spine and a “U“-shape between the prezygapophyses (it’s more trapezoidal).

I am tending to think that Naish and Sweetman (2011) are pretty spot on on their work, and it tells me that what I am looking at is quite likely to be a maniraptoran, and possibly a paravian or avialaean. The latter two options are possible because, just as the Ashdown vertebra has features in common with Oviraptorosauria, it has many of those features in common with Troodontidae as well, and some with dromaeosaurs. It is also very similar to many basal birds, although not so much Archaeopteryx (no hypapophyses, no pneumatic foramina, etc.). It even has some similarities with some alvarezsaurs, and this could place it outside of the Maniraptora entirely. But I am almost certain that the Ashdown vertebra does not represent a member of Oviraptorosauria.

Were there European Oviraptorosaurs?

Certainly possible, but the current swath of remains so far described do not appear to indicate this. One vertebra said to be oviraptorosaurian-ish is equally possible to be an abelisauroid by Darren’s suggestion, and there were other European abelisauroids (such as Tarascosaurus salluvicus and Genusaurus sisteronis) that permit. Europe contains many clades of theropod thought typical of Asia and North America, and contains dromaeosaurids, tyrannosauroids and alvarezsaurs, so its just possible that oviraptorosaurs (and therizinosauroids, and troodontids…) could end up here. In England especially, definitive tyrannosauroids are known, while the remainder are restricted to the Continent proper. My comments thus only refer to these specific cases, and currently, I would argue that no known material indicates there is an oviraptorosaur in England specifically, and probably not in Europe, and especially not in the Early Cretaceous.

[n1] In this case, Oviraptorosauria follows my argument here, and includes Protarchaeopteryx robusta and Incisivosaurus gauthieri (or sensu Senter, 2000, Protarchaeopteryx gauthieri, for which there is no effective difference), Caudipteryx zoui (including Caudipteryx dongi, and with the possible exclusion of IVPP V14350 as Caudipteryx sp. — Mickey and I are in general agreement that this specimen is very distinct, and I’ve illustrated their skulls in this manner here), Similicaudipteryx yixianensis, Microvenator celer, Avimimus portentosus, Nomingia mongoliensis, and Caenagnathidae and Oviraptoridae.

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4 Responses to Were There European Oviraptorosaurs?

  1. Wow, very thorough! Though to be fair, Naish & Sweetman did nickname it the “Asdown maniraptoran” not the “Ashdown oviraptorosaur”… doesn’t seem like that identification is anything more than a tentative suggestion. Obviously based on a single vert it’s near impossible to tell what it is, especially since, if this is close to its maximum size, it must be fairly derived or at least aberrant compared to whatever its larger relatives may be.

    • Undoubtedly. I was responding to some of the specific suggestions of Darren at TetZoo, which were more oviraptorosaur-oriented than the paper was (which as I noted was very careful in this regard). Darren and Sweetman did this on purpose, and it’s to their credit, but Darren hopes (perhaps) for a more faunally diverse Wealden than there may be evidence for, and I do not think the present evidence supports this. So my arguments are in reply to his blog post, instead.

  2. Pingback: DINOSAURICON A « Tsjok's blog

  3. Pingback: Are Scansoriopterygids Oviraptorosaurs? | The Bite Stuff

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