Hopeful Pterosaur(omorph)s

Lagerpetid by Rodolfo Nogueira

As we’ve seen, the Triassic was a period filled with all manner of charismatic animals, including reptilian platypuses and whales, praying mantis-like drepanosaurs, semi-aquatic dragons, pseudosuchian dinosaur mimics, and everything in between. We have not, however, in our Triassic adventures, yet directly touched on the typical touchstones of Mesozoic diversity: pterosaurs and dinosaurs. In part, that has been intentional: why focus on dinosaurs when there are so many other wonderful animals to learn about during the Triassic? But another, perhaps more interesting, reason is that dinosaurs and pterosaurs simply weren’t a particularly large or diverse component of Triassic ecosystems until the very end. I would argue that the dinosaur's reign didn’t really begin until the Triassic-Jurassic extinction event removed their pseudosuchian competitors. Pterosaurs, too, diversified during the Jurassic, although I'm not sure if anything was keeping them down before. Anyway, until the Jurassic, these would-be prehistoric paragons were living in the shadows of predatory rauisuchians, herbivorous aetosaurs, giant dicynodonts, and semi-aquatic phytosaurs. No revolution, however, comes from nothing. Dinosaurs and pterosaurs had ancestors too, and in this essay, we’ll focus on one their most distant relatives, the lagerpetids.

Slightly More Hopeful Dinosaurs

Lewisuchus--basalmost ornithischian? (from Ezcurra et al., 2019)

Dear me, it’s been awhile, hasn’t it? My tardiness in keeping this blog going has not been entirely intentional; 2020’s been a year for the records? I only hope it ends on December 31st and doesn’t continue on in some space-time warping extension into December 32nd. Nonetheless, I am motivated today to inform you all about a paper that brings together several topics I’ve written about in years past: silesaurids, Pisanosaurus, and the Triassic Ornithischian Crisis. Below, I will offer the briefest of recaps, but hit those links if you want a more complete picture.

Marine Snouters of the Triassic II: Gunakadeit Rising

Alaska's own Gunakadeit joseeae by the amazing Gabriel Ugueto, or @SerpenIllus on the Twitters.

A very long time ago, I posted an essay about one of my favorite groups of Triassic marine reptiles: thalattosaurs. These lizard-shaped swimmers, while generally similar in body form, differ from one another quite strongly in terms of feeding adaptations. While Anshunsaurus and Askeptosaurus may seem, to our modern eyes, rather vanilla in their clearly faunivorous dentition, others strain credulity. Xinpusaurus, for example, possesses a bizarre notched upper jaw and, in some specimens, an elongate premaxillary spear which overshoots the the lower jaw by an impressive degree, calling to mind swordfish and swordfish-snouted ichthyosaurs. Thalattosaurus and its “claraziid” brethren have reduced, shell-crushing dentition and snouts which curve downward—Hescheleria takes this trend to a puzzling extreme. Thalattosaurs also occupied a wide range of body lengths (1-5 meters). While some were more terrestrially capable than others, the group never seemed to stray far from the nearshore niche.

Walk This Way

The right manus of Camarasaurus. Note the columnar arrangement and virtual absence of fingers.

Late last year, I introduced you all to the Lessemsauridae, a group of near-sauropod "prosauropods" that grew unreasonably large—up to 12 tons in Ledumahadi mafube. There’s some disagreement about the posture of these enormous animals: in true, blue Sauropoda, the forelimbs are columnar, the hands are pronated, the weight is bore on the fingertips, and there is a reduction in phalanges and claws. This arrangement is present to some degree even in the earliest true sauropods like Melanorosaurus and Barapasaurus.

Don't knock my Smok or I'll clean your clock!

We miss you, Bill Watterson.

A few months ago, I wrote that my favorite paleo story of 2018 was the publication of Lisowicia bojani, a ridiculously large dicynodont from Poland. In that same post, I mentioned Smok wawelski, a similarly-sized predatory archosaur of uncertain phylogenetic affinities that very likely hunted Lisowicia. It strikes me that Smok might be unfamiliar to many of you out there in Readerland, so today’s quick post is a summary of what we know about this mysterious carnivore. By the way, I posted this Calvin & Hobbes strip because every time I hear the name Smok I immediately think of it.

Whale-Lizards of the Triassic III: Revenge of Eretmorhipis

You might fondly remember the two previous posts in this series: Part I and Part II which describe a particularly bizarre group of basal ichthyosauromorphs called hupehsuchians. Known for their "bony body tubes" and wide, toothless mouths, hupehsuchians are a surprisingly diverse group that includes five monospecific genera: Nanchangosaurus, Hupehsuchus, Eohupehsuchus, Parahupehsuchus, and Eretmorhipis. Eretmorhipis is the most recently-described hupehsuchian (Chen et al. 2015) but also one of the more mysterious, as the holotype does not include a skull or even cervicals. I should mention this is also the case with Parahupehsuchus although it's missing most of the tail, too.

Big Finish to 2018

Despite Sergey Krasovskiy's gorgeous art, it is not Crittendenceratops.

First of all, sorry for not writing anything in December. We spent half the month on vacation and the other half madly trying to finish things before the vacation and playing catch-up after the vacation. It was a good vacation; we went to Kauai. I don’t know if you’ve ever been to Kauai but it’s the complete opposite of Alaska, especially during December. I did some writing while on vacation but nothing serious and besides I didn’t have any of my reference material on-hand. However, I did work on a longer-term project that's been on my mind for awhile now. Details as they emerge.

Thanos Deserves Better

Thanos, the Mad Titan, disappointed with his namesake.

A new dinosaur was published today in Historical Biology: Thanos simonattoi, named after Sergio Simonatto, who discovered the specimen, but more visibly Thanos, the Marvel villain. It might not shock you to known that Rafael Delcourt's name is on this paper. A few months ago, he gave us the Etrigansauria, an unnecessary name that has designs on replacing the perfectly-good Neoceratosauria. Delcourt & Vidoi lori (2018) identify Thanos as an abelisaurid close to Brachyrostra. This all seems fine until you see the holotype:

They Might Be Giants

Ingentia prima by Jorge Gonzalez

Two recent news stories perked my interest recently—the descriptions of two new non-sauropod sauropodomorphs: Ingentia prima from the Late Triassic of Argentina and Ledumahadi mafube from the Early Jurassic of South Africa. Together, these animals (and two others which I’ll get to) form a clade of non-sauropod sauropodomorphs that achieved gigantism independently from true, blue sauropods, which is intriguing for a number of reasons.

An Update on Stem Turtles

The beaky noggin of Eorhynchochelys by...IVPP?

Couple things I need to talk about. First, it's been a very long time since I've blogged, which was not my intention (it never is). I hit a rough patch of writer's block, which was followed up by a 9-day stint at the hospital where I got a CF-related tune-up. Taxonomy Tuesday is not proving to be the rich well of inspiration I was hoping for, so while I still intend to write up Taxonomy Tuesdays, they almost certainly won't be weekly. Now then, right before I was admitted, I wrote this short post about a new stem turtle. I wrote about turtle origins way back in 2015 and I'm always excited when a new one pops up. Thankfully, in addition to this post, I'm halfway through essays about mesosaurs and tanystropheids, so regular blogging will commence soon.

Taxonomy Tuesday: Hyenas Are Not Dogs

The spotted,  or "laughing" hyena

Yes, I know it's Thursday. I got busy mid-week. Today's #TaxonomyTuesday is about hyenas, which, contrary to popular belief, are not related to dogs.

Taxonomy Tuesday: Snakes are lizards

Snek

I'm trying something new in an effort to post more often then once a month.

Once a week, on "Taxonomy Tuesday," I'll write a short post about some taxonomic weirdness that people might not think about. On this maiden voyage of "Taxonomy Tuesday," we'll talk about snakes...which are lizards.

We Can't Have Nice Things

Sinoceratops vs. Carnotaurus

Against all better judgement, I saw Jurassic World: Fallen Kingdom last night. It was terrible. Until last night, I’d never seen a movie that didn’t have a single original idea—Jurassic World 2 is a mish-mash of previous Jurassic Park/World concepts thrown into a blender and pureed. While there will be massive spoilers in this review, I kind of agree with John Conway that Jurassic World 2 is almost incapable of spoilers because you’ve seen this movie before. In fact, if you’ve seen the trailers, you know everything that happens; there are no surprises.

And away we go...

Faux Theropods

The skeleton of Effigia

Bit of a shorter post this month, as I'm prepping a photo-heavy review of the Creative Beast raptor toys that I just received. This month I’ve decided to tackle one of my absolute favorite groups of Triassic weirdos: shuvosaurids! They are a fairly obscure clade outside of paleo circles, consisting of only three (used to be four) named genera but shuvosaurids should be poster children for the concept of convergent evolution. These things are pseudosuchian theropod mimics, and not just theropods but ornithomimosaurs. Ostrich dinosaurs in the Triassic...but suchians!

One More Strange Reptile

Remember my post from last year about azendohsaurs and trilophosaurs? Well just the other day, paleoartist extraordinaire Gabriel Ugueto posted a sketch of something called Teraterpeton. I had no idea what this zany-looking reptile was, so I looked it up and was flabbergasted to find that it's a trilophosaur that is quite unlike Trilophosaurus. You'll notice that I did mention Teraterpeton in passing in that post, which must mean I didn't think it was a trilophosaur or at least was not unambiguously a trilophosaur. Turns out I'm incorrect--Teraterpeton is a perfectly good trilophosaur, and therefore an allokotosaur!

Adorable Triassic Pseudosuchians

Erpetosuchus sp. from North America

Erpetosuchids are one of those groups that I saw reference to somewhere, filed it away in the recesses of my brain, and didn’t remember again until I read the new paper by Nesbitt et al. (2018) about the brain and endocast of Parringtonia gracilis. There’s a gorgeous skeletal restoration on page 124 and that skull looked awfully familiar to me. Oh yes, it looks a whole lot like the skull of Erpetosuchus grandi, a taxon I first read about thanks to Benton & Walker (2002) probably a decade ago. With a little more digging, I found that the Erpetosuchidae is a small but charismatic family of mid-sized pseudosuchians with unusual dentition and surprisingly croc-like armor. This is one of those small, obscure groups of Triassic hellasaurs that I like to put in the spotlight, if even briefly.

The Camptosaurus Challenge

Camptosaurus dispar skeletal by Scott Hartman

If any of you dear readers follow me on Twitter (@zmiller1902) or any of my blogger colleagues (there’s a handy list at the bottom of this post) you’ve probably seen at least a few entries in the hashtag Camptosaurus challenge. For the deets, check out David Orr’s two posts on this very topic and the deluge of paleoart that it inspired. You’ll see that I have two rather terrible entries—both were rush jobs—but I was determined to put something respectable together last night and I’m pretty happy with the result:

Lesser-Known Running Lizards (minor update at the end)

by Jaime Headden, from Wikipedia

In the last post, I briefly mentioned a group of dromaeosaurs called unenlagiines. This is still a rather obscure group, especially to the general public, so I wanted to give these South American dromaeosaurs some much-deserved time in the spotlight.

This is a small group—only three (but possibly four or five) genera have been named. They are atypical dromaeosaurs for a number of reasons, foremost among them the elongate, narrow snout packed with minute teeth which lack serrations. While most appear to have been small, one of them was one of the largest dromaeosaurs, approaching Achillobater and Utahraptor in terms of overall size.

Nearly Birds

Adorable Serikornis sungei by Emily Willoughby

Something I really enjoy about paleontology is how quickly things can change. For example, when I was growing up, Dromaeosauridae was confined to half a dozen genera from two continents. If you wanted a complete list, you could check out Raptors: The Nastiest Dinosaurs from your local library. Now, though, Dromaeosauridae is more like Dromaeosauriformes because there are something like five distinct groups now: Halszkaraptorinae, Unenlaginae, Microraptorinae, Dromaeosaurinae and Velociraptorinae (those last two are usually stuck together in a monophyletic Eudromaeosauria). It used to be that dromaeosaurs came in two flavors: large and small. Now you’ve got swan-necked, duck-billed dromaeosaurs; piscivorous, leggy dromaeosaurs; tiny, potentially volant dromaeosaurs; and larger “classic” predatory dromaeosaurs.

All this has happened in the last twenty years. Heck, nobody knew about Halszkaraptor until a few weeks ago.

Chilesaurus and Avian Arm Folding

Chilesaurus diegosuarezi by the impeccable Jaime Headden

Ever since the publication of supreme oddball Chilesaurus (eat your heart out, Halszkaraptor), I’ve been dying for somebody out there to do a full description of the critter’s unusual skeleton. As Chilesaurus may hold the key to our understanding of early ornithischians (or not), this is an animal in dire need of detailed study. This past Sunday, a paper was published in a journal that I can’t pronounce—Ameghiniana—and it is not that description. However, it is very interesting, and since I imagine many of you don’t have access to, uh, Ameg-HEE-ana (?), I thought I might summarize the juicy parts here.