Sunday, January 7, 2018

Crystal Ball for 2018

For 2018's first post, I once again peer into the mists of futurity and offer dinosaur-centric predictions on the year to come.

Will I once again be called upon to fight a mammoth inside a building? Well, that's always the dream.

This is going to be organized similar to last year's, the major difference being the absence of "what I'd like to see" (those haven't changed; I didn't really expect I'd get any).

Basal dinosaurs and dinosaur cousins:
I think it's safe to assume that last year's Ornithoscelida controversy is just the beginning, and that we're going to see a lot of back-and-forth before a new consensus emerges about the relationships of the major lineages of dinosaurs. As we steer directly into the land of contention, it's always helpful to remember that the closer you get to the splitting points of lineages, the harder it is to determine who's on which branch. I'm going to predict at least two publications on the relationships of the main branches, plus a new dinosaur cousin.

Non-coelurosaurian theropods:
I'm feeling "noasaurid" here for some reason, so let's say a significant publication on a noasaurid, either a new taxon or restudy of an existing taxon. Actually, I feel good about abelisaurs in general, so let's also add that there will be a significant abelisaur publication as well (not the same as the noasaurid paper; double counting would just be cheating). As for the others, I also predict a new coelophysoid-ish theropod (the "ish" to mean somewhere between the base of Neotheropoda and the base of Averostra).

Coelurosauria:
I did pretty well with this one last year; doubt I'll get it that well again, but what the hey? 1) at least one new North American ornithomimid; 2) a respite from YANOs (Yet Another Nanxiong Oviraptorid), but at least one new North American oviraptorosaur; 3) a new therizinosaur; 4) a new alvarezsaur; 5) for bonus points, a new giant troodont (with all these links, I ought to just set up a page here to briefly define these groups; oh, well, another log for the fire). We've got giant ornithomimosaurs, giant oviraptorosaurs, and giant dromaeosaurs, why not a giant troodont? For credit there has to be an actual description, not just a press release, and the animal has to be at least 6 meters long.

"Prosauropoda":
I'm going to predict the prosauropods to hold steady. I'll roll over last year's prediction of "maybe one new taxon, plus more on the paleobiology of the usual suspects (Massospondylus and Plateosaurus)."

Sauropoda:
First off, it's been nearly three years since Brontosaurus burst back through the door. I'm a little surprised that no one has issued a formal critique, given some of the commentary at the time. Anyway, I'm predicting that 2018, like 2016, will be quiet on the "Morrison diplodocid taxonomy" front. On the other hand, I'm predicting a good year for titanosaurians: at least five new taxa.

Thyreophora:
Stegosaurs tend to travel under the radar most years, but this year I'm predicting we get something more, perhaps a major paleobiological publication, a description of an unusual new species, something that could get a bit of attention outside the field. I am also predicting news on the Late Cretaceous nodosaurs of western North America.

Marginocephalia:
The basal ceratopsians shut me out last year, but I'm going to that well again and predict a new basal ceratopsian. For ceratopsids, I predict at least one new example of both centrosaurines and chasmosaurines. For pachycephalosaurs, I predict that at the end of the year we still won't know what a pachycephalosaur hand looks like.

Ornithopoda:
Ornithopoda has gotten more awkward in recent years, given its sudden inability to maintain a firm grip on its basal representatives. As with the base of Dinosauria, this is not something that is going to go away anytime soon. The non-hadrosaurid iguanodonts joined the basal ceratopsians last year and skunked me, but I'll also go back to them and predict at least one new taxon. I think hadrosaurids will have a good 2018; I'm predicting at least two new saurolophines/trad hadrosaurines and another notable paleobiology publication.

Other predictions:

1) We'll clear 35 new non-avian dinosaur species again this year.

2) At least two of the remaining possibilities will come off of "Coming Attractions". For full credit, I predict that either the Nova Scotia prosauropod or the Proctor Lake hypsilophodont will be among them.

3) Someone finds a significant Western Interior Seaway "bloat-and-float" specimen, some nodosaur or hadrosaur in Kansas or Iowa or similar. It doesn't have to be described, just publicized.

4) A "Saints and Sinners Quarry" animal is described, but it's not the theropod; it's the pterosaur.

5) The Triassic comes through again and produces another bizarre, unexpected tetrapod. We got Shringasaurus last year, which looks like something from a '50s sci-fi movie. Chinlestegophis and Pectodens weren't quite as wild but are certainly not to be despised. (Also, was I the only one who saw Avicranium and thought "there's the head of Protoavis"? [note, 2018/01/09: Chinle is close enough to Dockum for me in this case])

Completely for fun: Conulariid soft tissue, allowing classification after all these years. If hyoliths can come through, why not conulariids?

14 comments:

  1. Though I said this the last two years, I think we can expect Lori to actually be published this year.

    I'm really hoping we get some kind of derived stegosaur that isn't from the Morrison, instead from some Cretaceous rocks.

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    1. Oh yeah, and I really hope we get a break from the YANOs. There is no way all of the ones named so far are valid.

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    2. Yeah, I thought about Lori, but it came down to the feeling that if someone said it was coming out (and Mickey Mortimer said the paper was nearly ready for submission over at The Theropod Database Blog), it wouldn't be much a prediction on my part.

      A Cretaceous stegosaur would be nice (we know about Wuerhosaurus, so why not a Yixian form? Surely in all that time one might have keeled over and floated into a lake?).

      To be fair to the YANOs, the Nanxiong isn't dated all that well yet, so conceivably we might be looking at a smaller number of discrete lineages over a few million years. Also, they weren't huge animals, so it's not quite as wild to think they may have had a significant radiation (although it would certainly be easier if they were rodent-sized!).

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  2. There's a chance that several dinosaur genera may be sunk this year - just as Opisthocoelicaudia was essentially (but AFAIK not formally) found to be a junior synonym of Nemegtosaurus last year. Some potential synonyms have been hinted at, but need a bit more material to seal the deal (Miragaia/Dacentrurus, Nomingia/Elmisaurus, Deltadromeus/Bahariasaurus).... maybe this is the year for at least one of these.

    2018 might be make-or-break for the "Toroceratops" hypothesis. Hope so... this thing needs resolving (e.g. osteohistology of Triceratops vs Torosaurus specimens).

    Agree on the possibility of a new noasaurid. There's a few floating around in the ether. (This doesn't include the possibility that Afromimus is re-described as a noasaurid or related ceratosaur.)

    On the stegosaur front, maybe Dravidosaurus will be confirmed as a Late Cretaceous stegosaur. Material from the Dravidosaurus type quarry is apparently under active study.

    The enigmatic Yandangornis could finally find a home. Is it a basal bird, or a very bird-like non-avian theropod?

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    1. We've definitely been on the "splitter" side of the dial for a while, albeit with a few notable exceptions.

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    2. Tell me about it, the ceratopsians are ridiculous.

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  3. Hi Justin:
    Lifelong Minnesota resident (St. Paul) who has always been interested in the history of Minnesota geology. My major in college was Biochem but I had the pleasure to take a semester elective in Geology at the University of St. Thomas.
    Easy "field trips" to walk t over to the Mississippi at the end of Summit Ave. and study Ordovician strata. Fun times! Many hours over the years collecting invertebrate fossils at TC Brickyard, "Wangs" road cut in Goodhue, County, etc. So it was exciting to "discover" your Blog!!! Great information and discussions!! Fantastic links to further readings as well. Keep up the great work!

    Best,
    Bill Peterson - Welch, MN
    wgpeterson@icloud.com

    (ps: I also have a habit of pulling off the road to study an interesting road cut! )

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    1. Hi, Bill;

      Thank you for stopping by! I'm glad you like it!

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  4. Hi Justin,

    Let me evaluate your dinosaur-centric predictions for this year:

    1. Basal dinosaurs and dinosaur cousins: Dracohors erected by Cau (2018) to accommodate Silesauridae and Dinosauria.

    2. Non-coelurosaurian theropods: Etrigansauria erected to accommodate Abelisauridae and Ceratosauridae by Delcourt (2018)

    3. Coelurosauria: Your prediction of respite from YANO proved right with the description of he caenagnathid Anomalipes by Yu et al. (2018); Anomalipes is the southernmost record of Caenagnathidae from East Asia. Ever though your prediction of a new ornithomimid remains to be fulfilled, Arkansaurus was finally officially described after being a nomen nudum for decades.

    4. "Prosauropoda": The new basal sauropodomorph Bagualosaurus is described from Brazil.

    5. Sauropoda: You predicted 2018 to be a good year for titanosaurs, and Sallam et al. (2018) describe the youngest African titanosaur outside Madagascar, Mansourasaurus, from the land of pyramids and mummies. Apaldetti et al. (2018) illuminate the diversity of early sauropod evolution when they place the new sauropod Ingentia but also Lessemsaurus and Antetonitrus in the new family Lessemsauridae. You didn't think, however, that a diplodocoid would be named from Asia, and Lingwulong makes clear that the supposed absence of Diplodocoidea from Asia was an artifact of poor sampling.

    6. Thyreophora: You correctly predicted North American nodosaurid news for this year, as Acantholipan has been described from marine deposits in Mexico. While you were surprised to see Paul Penkalski erect Platypelta for a handful of Euoplocephalus specimens, his treatment of Dinosaur Park Formation Anodontosaurus makes sense given its temporally older age than A. lambei and the fact that HCF dinos are distinct generically from DPF genera. We closed off July with a new ankylosaurid from southern Laramidia, Akainacepalus. The genus Jinyunpelta is notable for showing that the tail club appeared in ankylosaurids as far back as the Albian, possibly to respond to the emerging threat of giant carcharodontosaurs and tyrannosaurs in Asia and North America.

    7. Ornithopoda: Diluvicursor became the first new Australian ornithopod species described in nearly 20 years, and the non-hadrosaurid hadrosauriforms Bayannurosaurus and Choyrodon have been described so far, as well as the hadrosaurid Laiyangosaurus.

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    1. I've got a few months yet, but overall my strategy isn't working as well as I'd hoped (a significant chunk of these came from skimming through SVP abstracts from a few years ago, eliminating the stuff that was published, and trying to guess what might be on its way).

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    2. Hi Justin,

      With respect to your prediction for this year regarding basal dinosaurs and dinosaur cousins, Sarigul et al. (2018) describe a new silesaurid, Soumyasaurus, from a dentary found in the Post Quarry (which also happens to be the type locality of another silesaurid, Technosaurus). Although Soumyasaurus is a silesaur like Technosaurus and its holotype is catalogued under a catalogue number that includes different taxa, just like the holotype dentary and premaxilla and dentary of Technosaurus, Soumyasaurus has dentary teeth more similar to that of Asilisaurus than to Technosaurus, indicating that two distinct silesaurids co-existed in the middle Norian (late Lacian) of Texas.

      Volkan Sarıgül; Federico Agnolín; Sankar Chatterjee (2018). Description of a multitaxic bone assemblage from the Upper Triassic Post Quarry of Texas (Dockum group), including a new small basal dinosauriform taxon. Historia Natural, Tercera Serie. 8 (1): 5–24. http://fundacionazara.org.ar/img/revista-historia-natural/tomo-15/VolkanSarigul-5-24.pdf

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    3. Wachtlerosaurus might count for #5

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    4. Regarding #4, the Saints and Sinners Quarry pterosaur has been formally named Caelestiventus hanseni by Britt et al. (2018). Because all other previously named Triassic pterosaurs except Arcticodactylus have been described from mainland Europe, Caelestiventus is the first valid Triassic pterosaur from North America.

      Britt, Brooks B.; Dalla Vecchia, Fabio M.; Chure, Daniel J.; Engelmann, George F.; Whiting, Michael F.; Scheetz, Rodney D., 2018. Caelestiventus hanseni gen. et sp. nov. extends the desert-dwelling pterosaur record back 65 million years". Nature Ecology & Evolution. doi:10.1038/s41559-018-0627-y. ISSN 2397-334X.

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