Tuesday, August 18, 2026

My favorite dinosaur book as an adult- Maisch's "Imaginary Dinosaurs"

So as a paleontologist, there are certain types of media that the layman expects to be appealing. The most basic is probably the dinosaur movie, like the latest Jurassic World, and we can all insert our own criticisms there that need no elaboration. A bit more sophisticated are dinosaur documentaries, but as cool as it is to see a hyper-accurate CG portrayal of Shuvuuia or something, it's at its core eye candy that doesn't really engage the mind. But what about dinosaur books?

I own a ton of them, as I'm sure most readers do. As a kid, I grew up reading Sattler's 1983 "The Illustrated Dinosaur Dictionary",  Glut's 1972-1992 "The ( /New/Complete) Dinosaur Dictionary", Paul's 1988 "Predatory Dinosaurs of the World' and Lambert's 1990 "The Dinosaur Data Book", the latter being the source of my website's name. But you grow up, gain access to the primary literature, and suddenly even something as detailed as Glut's (1997-2008) "Dinosaurs the Encyclopedia" series is sorta useless since you have all that info already.

Now note I'm not including collections of technical papers like "The Dinosauria", symposium compilations, or the Princeton series. Ditto monographs like Hou on Mesozoic birds, Powell on South American titanosaurs or Madsen on Allosaurus. Those are great, but really more of a journal volume than a single-authored book. Among the latter you do have "field guides" like Martyniuk's or Paul's which are both mostly eye candy, with some new taxonomy to address. And of course you have foreign books like Dong's (1992) "Dinosaurian Faunas of China" or Dong et al.'s (1991) "The Age of Dinosaurs in Japan and China" that contain obscure information and figures, but they're not exactly detailed or entertaining to read.

Prodeinodon mongoliensis in mesial view (Mortimer, 2009; courtesy of the AMNH).

So as I was researching some obscure taxon, I came across a page selling "Imaginary Dinosaurs" "from Aachenosaurus to Zatomus", self published by Michael Maisch, with its topic being taxa that were once thought to be dinosaurs but aren't anymore. I've never seen a book or study on that subject before, and indeed that's why I made a series on it for this blog in 2010- the relevant information's usually spread around old journals and once a taxon is transferred from Dinosauria, the details aren't generally repeated. I ordered it and it arrived yesterday.  I've only read through the A entries so far (Aachenosaurus, Actiosaurus, Aggiosaurus, Albisaurus, Anthodon, Asiamericana (ended up being a dinosaur after all, but he justifies it), Avipes, Azendohsaurus), but that's 70 pages and I feel it gives a substantial example of the book's content and quality.

So the basic format is closest to Glut's "Dinosaurs the Encyclopedia" series in that you get multiple pages of information on each taxon with figures reprinted from the literature in black and white. Right away I was struck by the informal tone, using correct technical terminology but also not something you would see in a technical journal. For example, regarding Fritsch deciding Iguanodon? albinus was indeterminate but not Iguanodon and renaming it Albisaurus scutifer, Maisch writes- 

"Let's take this slowly, so that we can all fully marvel at the flawless logic of Professor FRITSCH. His material is so lousy, he assures us, that it  is impossible to be determined with certainty. And it is not an Iguanodon. So the only logical consequence is... no, not to regard it as Reptilia incertae sedis, or to be at least content with calling it an indeterminate dinosaur, but to put the stuff, which he himself calls "indeterminable" into a new genus. Now that's a way to tackle taxonomy."

Or when dealing with the Wikipedia page for Aachenosaurus-

"
As a sıde note, the always well-informed and trustworthy Wikipedia tells us (as of September 2018) that SMETS discovered and published Aachenosaurus at the 31st of October 1888. Wow, that was a pretty fast publication! May actually explain why he blundered so much. Producing a 23 pages paper in a single day - after dinosaur-digging fieldwork! - is quite an achievement. And SMETS must really have been a true prophet, publishing a note on his 1888 discovery already in 1887 (SMETS 1887a). And most importantly, he was only born the day he discovered Aachenosaurus, as his birth-and-death dates are given as 31st of October 1888 to 1890. Maybe that's true. 1 haven't come up with much better dates (but he was born in 1857), so I can't falsify it. I hope someone will write his biography. I'd sure read it.
But as I personally consıder Wikipedia just as another means of dumbing down the masses and keep people away from reading books and the primary literature, I will not correct that hilarious bullshit. Maybe someone else feels inclined to (the 31st of October 1888, by the way, was actually the day Louis DOLLO delivered his destructive talk on Aachenosaurus, see below. So someone was obviously a bit drunk, but at least retained a half-functional brain, when writing about Aachenosaurus on Wikipedia)."

LOL That's exactly how I would write on this blog. Though I must note three pages later, Maisch cites a figure to Wikimedia commons, so maybe it's a little more useful than he lets on. ;)

One of the most interesting aspects of the book is the level of biographical detail Maisch goes into about each author. The Aachenosaurus entry is as much about Smets as it is about the fossils, and again that's not something you can usually find in a convenient and entertaining form. He doesn't shy away from the personal and messy issues that result when scientists are human, which I appreciate. At times this approaches hot goss, or spilling the tea, or whatever the kids are saying now- "One has to remember that DOLLO had his share of bullying himself. And he just went through one of these phases when the affair took place. His Belgian colleagues watched the scientific success of the French-born "immigrant" with envy, and they tried to hamper his studies in every possible way for many years. This reached up to a point where his beloved Iguanodons were once taken away from him by the museum's director Edouard DUPONT, and he was relegated to work in the cellars, on fish (if you don't believe it, read Othenio ABEL's, one of DOLLO's closest personal friends, interesting biographical sketch from 1928. In today's literature and biographies, all sugar-coated, these facts, deeply embarrassing for Belgian paleontology, are usually completely swept under the carpet), a fate he shares with the great 20th century reptile paleontologist Olivier RIEPPEL, who was forced to do the same at the Zurich Museum under the directorship of Prof. Emil KUHN-SCHNYDER Both DOLLO and RIEPPEL made the best of their situation and produced some beautiful paleoichthyological work". I mean, OOF, sorry to hear that Olivier...

A nice thing that wasn't a guarantee given the book's format is that the entries seem written in order, so you won't get repeats of details, and you build up a knowledge of paleontology bios as you read. Instead, Maisch will be like "X person, who you recall from that ex-dinosaur" and "but he'll make that mistake again, as we'll see with future ex-dinos Y and Z." So reading it through is more valuable than treating it as an encyclopedia.

I mentioned I had a similar project in mind for this blog in 2010, so do Maisch and I cross paths? Yes, for Actiosaurus at least, so far. A supposed dinosaur that was then weirdly assigned to Ichthyosauria by Huene, I looked at the figure and thought it most closely resembled a Pachystropheus humerus (see https://theropoddatabase.blogspot.com/2010/06/actiosaurus-is-choristodere-not.html ). Maisch writes "Credit for being the first one to suggest this should go to dinosaur enthusiast Mickey MORTIMER, however, who already pointed this possible identification out in a blog post in 2010 (https://theropoddatabase.blogspot.com/2010/06/actiosaurus-is-choristodere-not.html). Unfortunately, for whatever reasons, Mr. MORTIMER almost never publishes his results in the form of scientific papers. A blog-post does not count as a paper in scientific literature. Nonetheless, it was his idea, and may be the correct one."
Misgendering aside, that's great!  Credit is all that I've ever asked for. So extra kudos to Maisch. "Whatever reasons" this time include- I didn't have the fossils, I'm not an expert on all the various Triassic tetrapods that might be implicated, and Fischer had texted me afterward and said they were working on it and I probably got it right.

As a final positive, the end of the Azendohsaurus entry notes "What is totally superfluous, though, is their new taxon "Allokotosauria". It is nothing else but Alfred Sherwood Romer's Trilophosauria, erected in 1956, in new clothes. There is no need to coin a new fashionable clade name just to replace a well-established pre-cladistic one. Trilophosauria has priority, period. Azendohsaurus is not an "allokotosaur" but simply a trilophosaur. And we old-school paleontologists know bloody well what a trilophosaur is." Segnosauria remembers, Maisch. And in Mammalia, Lipotyphla, Archonta, Ungulates, Artiodactylia, etc.. You don't need a new term every time a clade slightly changes content. Does that make me old-school?! No, wait fellow kids, I like K-Pop Demon Hunters too!...

Prodeinodon mongoliensis in distal view (Mortimer, 2009; courtesy of the AMNH).

So that all looks good, but what about my usual scathing commentary?  As might be expected of a self-published work, there are some grammatical issues. Maisch uses "1890ies" instead of 1890s or eighteen-nineties, "TV-series" instead of TV series, and the occasional typo as you may have noticed in my quotes.

There's also the occasional factual inaccuracy, like when Maisch calls Thecodontosaurus a prosauropod. That would mean it's closer to Plateosaurus than to sauropods, and it's near certainly not. Maybe this is old-fashioned Maisch fighting against the new-fangled orthodoxy, but at least point that out like he does for Trilophosauria and Laelaps

More objectively, regarding Azendohsaurus Maisch says "DUTUIT further announces that a full description of all the material of his new form will follow. It has not appeared to the present date, not by him or anyone else." And this is in 1972, long before Jalil and Knoll's 2002 SVP abstract on new postcrania. BUT Maisch himself cites "GAUFFRE (1993) [who] provided a detailed redescription" of the initial material.

OR on pages 30-31 involving Actiosaurus, he says "I am not fully convinced of the Pachystropheus interpretation. The morphological differences between the two taxa as the considerable size difference makes me suspicious (Pachystropheus is much, much smaller)." Morphological variation, whatever, but back in that 2010 post I wrote "It is also within the size range of Pachystropheus specimens (greatest transverse width 25 mm compared to 13-35 mm)." Was I wrong? You didn't say I was....

My biggest disappointment is that so far Maisch usually doesn't use new data to better understand these ex-dinosaurs. Like on my blog I looked into what Actiosaurus was, what kind of hybodont Priscavolucris was, what kind of ichthyosaur Rachitrema was, where Bathygnathus fell out among sphenacodonts, etc.. And so far, Maisch is usually content to give the most recent opinion and just go with that. But take Aachenosaurus for example, that was found to be two different plant taxa by Hovelacque (1890) - Aachenoxylon multidens and Nicolia moresneti. Now I'm no paleobotanist, but I'd be very surprised if these taxa  named from wood pieces in 1890 are still considered valid. And just what kind of plant are they from? Surely the field's expanded hugely in the last 120 years?

The one exception is that Maisch tries for Avipes (which I didn't realize was destroyed). So he correctly says it seems unique, so shouldn't be a nomen dubium. But then he says "It also invalidates RAUHUT & HUNGERBUHLER's (1998) argument that the taxon does not show any theropod features. Proximal fusion of the metatarsals 2-4 is a theropod feature. A very derived one, actually."
But that's like saying inventing computers is a primate feature.  I'm not going to check the condition in all coelophysoids now, but the fusion in most seems to be confined to the most proximal area by the distal tarsals. Is an elmisaur plus avialan character really a theropod character? And sure maybe you're generalizing and saying only neotheropods have ANY kind of metatarsal fusion. But then WHY would you say "I agree with the conclusion that the taxon must nonetheless be considered Archosauria incertae sedis."?! Is it just the lowest common denominator of all the taxa mentioned by Norman as having digitigrade pedes in 1990? I stand by my statement on the Database- "non-ornithodiran digitigrade taxa like basal crocodylomorphs, shuvosaurids, proterochampsians and Langobardisaurus have metatarsals which lay diagonally over each other proximally, whereas Lagerpeton, Lagosuchus, Silesaurus and coelophysids lack much overlap as in Avipes. Pending further comparison it is here placed as Ornithodira incertae sedis."


But in general, I'm loving this book. Can't wait to get through all the entries and learn more. You can order it here for only $13.
https://www.amazon.com/dp/1726812189

Second best dinosaur book (given my earlier restrictions) as an adult is Paul's Dinosaurs of the Air, btw.

 

Reference- Maisch, 2018. Imaginary Dinosaurs from Aachenosaurus to Zatomus. The Astounding History of the Dinosaurs that Never Were. 293 pp.

Friday, January 16, 2026

Do theropods described in Science and Nature get fully described eventually? Fifteen years later...

So here's a fun one to finish up the year (got delayed due to computer issues; yes, more Titanosaurus is coming, but Curtice's excellent blog post on the unreliability of illustrations makes it at least somewhat less relevant). Over fifteen years ago, I wrote "Do theropods described in Science and Nature get fully described later?" As I summarized in that post- "Basically, we have a system that rewards publishing in Nature and Science (the so-called tabloids) despite the fact papers in those journals are universally thought to be too short due to space restrictions.  The usual response is that Nature/Science papers are just meant to be preliminary announcements that will be followed by more detailed coverage later.  But how often does this actually happen?" So that was 2010. Where do we stand in 2025? Surely these taxa have been described in the past FIFTEEN years?!

First of all, I'll say that for better or worse the HUGE expansion of supplementary information has meant that the basic problem no longer needs to exist. There are plenty of taxa described in the tabloids recently that get tens of pages worth of detailed description and figures in the supp info (e.g. Halszkaraptor).  I miss the days when you didn't have to also comb through what is basically an abridged description in the paper proper for details missed in the supp info, or copy the supp info description to another file to read alongside looking at the figures, or have to wait to read the supp info to even know what the taxon list was for Jenkins et al.'s (2025) amniote phylogenetic analysis (no, the other Jenkins). And the tabloids' supp info is free unlike a certain journal named after chalk, so they deserve credit for that.

But for this update, we're sticking with taxa named by September 2010. As an additional rule, I'm only counting redescriptions of the type material, not new specimens being described later, though I will mention those. Also, this only concerns anatomy, so if the material was later used in an analysis about function, growth, taphonomy, etc. that doesn't count toward getting the basic description out there.


Eoraptor
Sereno, Forster, Rogers and Monetta, 1993. Primitive dinosaur skeleton from Argentina and the early evolution of Dinosauria. Nature. 361, 64-66.
Redescription in progress for over a decade for publication as a JVP monograph. Yeah, it's probably a sauropodomorph now, but we got the redescription three years later-
Sereno, Martinez and Alcober, 2013. Osteology of Eoraptor lunensis (Dinosauria, Sauropodomorpha). Journal of Vertebrate Paleontology. 32(Supplement to 6), 83-179.

Limusaurus
Xu, Clark, Mo, Choiniere, Forster, Erickson, Hone, Sullivan, Eberth, Nesbitt, Zhao, Hernandez, Jia, Han and Guo, 2009. A Jurassic ceratosaur from China helps clarify avian digital homologies. Nature. 459, 940-944.
Not redescribed. Redescribed in Stiegler's (2019) unpublished thesis, which is a step closer.

Masiakasaurus
Sampson, Carrano and Forster, 2001. A bizarre predatory dinosaur from the Late Cretaceous of Madagascar. Nature. 409, 504-506.
Carrano, Sampson and Forster, 2002. The osteology of Masiakasaurus knopfleri, a small abelisauroid (Dinosauria: Theropoda) from the Late Cretaceous of Madagascar. Journal of Vertebrate Paleontology. 22(3), 510-534.
Also new material described by Carrano et al. (2011).

Baryonyx
Charig and Milner, 1986. Baryonyx, a remarkable new theropod dinosaur. Nature. 324, 359-361.
Charig and Milner, 1997. Baryonyx walkeri, a fish-eating dinosaur from the Wealden of Surrey. Bulletin of the Natural History Museum of London (Geology). 53, 11-70.

Giganotosaurus
Coria and Salgado, 1995. A new giant carnivorous dinosaur from the Cretaceous of Patagonia. Nature. 377, 224-226.
Not redescribed yet except for the braincase in 2002 (Coria and Currie). This is sadly still true, although Hendrickx et al. (2014) figure the quadrate in all views (mislabeled Shaochilong in the caption for Figure 11), Novas et al. (2013) figure the maxilla and dentary, Eddy and Clarke (2011) figure the lacrimal and ectopterygoid.

Siamotyrannus
Buffetaut, Suteethorn and Tong, 1996. The earliest known tyrannosaur from the Lower Cretaceous of Thailand. Nature. 381(6584), 689-691.
Not redescribed. Redescribed in Samathi's (2019) unpublished thesis, which again is a step closer.

Dilong
Xu, Norell, Kuang, Wang, Zhao and Jia, 2004. Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids. Nature. 431, 680-684.
Not redescribed, though White (2009) briefly described the metatarsus and Kundrat et al. (2020) described the endocast.

Guanlong
Xu, Clark, Forster, Norell, Erickson, Eberth, Jia and Zhao, 2006. A basal tyrannosauroid dinosaur from the Late Jurassic of China. Nature. 439, 715-718.
Not redescribed. Redescribed in Choiniere's (2010) unpublished thesis. There's some useful information in Ke et al. (2024) on its tooth replacement and Yu et al. (2015) on its manual motion.

Juravenator
Gohlich and Chiappe, 2006. A new carnivorous dinosaur from the Late Jurassic Solnhofen archipelago. Nature. 440, 329-332.
Gohlich, Tischlinger and Chiappe, 2006. Juravenator starki (Reptilia, Theropoda) ein neuer Raubdinosaurier aus dem Oberjura der Sudlichen Frankenalb (Suddeutschland): Skelettanatomie und Weichteilbefunde. Archaeopteryx. 24, 1-26.
We actually got an even better re-redescription of this as-
Chiappe and Gohlich, 2011. Anatomy of Juravenator starki(Theropoda: Coelurosauria) from the Late Jurassic of Germany. Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 258(3), 257-296.

Scipionyx
Dal Sasso and Signore, 1998. Exceptional soft tissue preservation in a theropod dinosaur from Italy. Nature. 392, 383-387.
Described in depth in Signore's thesis, which isn't published.  Dal Sasso and Maganuco are writing a monograph which Auditore said would be out in 2009 or early 2010, but it seems to be delayed. Hey, we got it the next year-
Dal Sasso and Maganuco, 2011. Scipionyx samniticus (Theropoda: Compsognathidae) from the Lower Cretaceous of Italy: Osteology, ontogenetic assessment, phylogeny, soft tissue anatomy, taphonomy, and palaeobiology. Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano. 281 pp.

Pelecanimimus
Perez-Moreno, Sanz, Buscalioni, Moratalla, Ortega and Rasskin-Gutman, 1994. A unique multitoothed ornithomimosaur dinosaur from the Lower Cretaceous of Spain. Nature. 370, 363-367.
Redescribed in Perez-Moreno's (2004) unpublished thesis (which everyone refuses to distribute...). BUT, we're partway to resolution with the postcrania being redescribed-
Cuesta, Vidal, Ortega, Shibata and Sanz, 2022 (online 2021). Pelecanimimus (Theropoda: Ornithomimosauria) postcranial anatomy and the evolution of the specialized manus in Ornithomimosaurs and sternum in maniraptoriforms. Zoological Journal of the Linnean Society. 194(2), 553-591.

Shuvuuia
Chiappe, Norell and Clark, 1998. The skull of a relative of the stem-group bird Mononykus. Nature. 392, 275-278.
Not redescribed. The skull was redescribed in Dufeau's (2003) unpublished thesis. There are useful photos in Chiappe et al. (2002) and Sereno (2001). I took pictures of all the postcranial specimens at the AMNH, so it's not affecting me THAT much, but is still bad for the community. Suzuki et al. (2002) described IGM 100/120, but this may be closer to Parvicursor

Mononykus
Perle, Norell, Chiappe and Clark, 1993. Flightless bird from the Cretaceous of Mongolia. Nature. 362, 623-626.
Perle, Chiappe, Barsbold, Clark and Norell, 1994. Skeletal morphology of Mononykus olecranus (Theropoda: Avialae) from the Late Cretaceous of Mongolia. American Museum Novitates. 3105, 1-29.

Falcarius
Kirkland, Zanno, Sampson, Clark and DeBlieux, 2005. A primitive therizinosauroid dinosaur from the Early Cretaceous of Utah. Nature. 435, 84-87.
Zanno, 2006. The pectoral girdle and forelimb of the primitive therizinosauroid Falcarius utahensis (Theropoda, Maniraptora): Analyzing evolutionary trends within Therizinosauroidea. Journal of Vertebrate Paleontology. 26(3), 636-650.
Zanno, 2010. Osteology of Falcarius utahensis: Characterizing the anatomy of basal therizinosaurs. Zoological Journal of the Linnaean Society. 158, 196-230.
Smith, Zanno, Sanders, Deblieux and Kirkland, 2011. New information on the braincase of the North American therizinosaurian (Theropoda, Maniraptora) Falcarius utahensis. Journal of Vertebrate Paleontology. 31(2), 387-404.
Lautenschlager, Rayfield, Perle, Zanno and Witmer, 2012. The endocranial anatomy of Therizinosauria and its implications for sensory and cognitive function. PLoS ONE. 7(12), e52289.
We've been mostly spoiled with this taxon, also getting a skull description with new materials (Freimuth and Zanno, 2025 online) among others. Could use better work on the pedal phalanges though...

Beipiaosaurus
Xu, Tang and Wang 1999. A therizinosauroid dinosaur with integumentary structures in China. Nature. 399, 350-354.
Not redescribed. Here's exactly what I want to see from all of these type specimens-
Xu, Cheng, Wang and Chang, 2003. Pygostyle-like structure from Beipiaosaurus (Theropoda, Therizinosauroidea) from the Lower Cretaceous Yixian Formation of Liaoning, China. Acta Geologica Sinica. 77(3), 294-298.
Liao and Xu, 2019. Cranial osteology of Beipiaosaurus inexpectus (Theropoda: Therizinosauria). Vertebrata PalAsiatica. 57(2), 117-132.
Liao, Zanno, Wang and Xu, 2021. Postcranial osteology of Beipiaosaurus inexpectus (Theropoda: Therizinosauria). PLoS ONE. 16(9), e0257913.
There's also a more articulated skeleton with complete skull figured by Xu et al. (2009) that has yet to receive a detailed description.

Incisivosaurus
Xu, Cheng, Wang and Chang, 2002. An unusual oviraptorosaurian dinosaur from China. Nature. 419, 291-293.
Balanoff, Xu, Kobayashi, Matsufune and Norell, 2009. Cranial osteology of the theropod dinosaur Incisivosaurus gauthieri (Theropoda: Oviraptorosauria). American Museum Novitates. 3651, 35 pp.
Xu et al. (2010) also briefly described two juvenile skeletons in Nature as Similicaudipteryx, but these have been recently suggested to be Incisivosaurus (Xu, 2020; and have not been redescribed in detail yet, ironically).

Caudipteryx
Ji, Currie, Norell and Ji, 1998. Two feathered dinosaurs from northeastern China. Nature. 393, 753-761.
The type specimens haven't been redescribed, though Zhou et al. (2000) and Zhou and Wang (2000) did describe others in more depth.

Gigantoraptor
Xu, Tan, Wang, Zhao and Tan, 2007. A gigantic bird-like dinosaur from the Late Cretaceous of China. Nature. 844-847.
Not redescribed. Mandible redescribed by Ma et al. (2017).

Mei
Xu and Norell, 2004. A new troodontid dinosaur from China with avian-like sleeping posture. Nature. 431, 838-841.
Not redescribed. A second specimen was described by Gao et al. (2012)

Sinovenator
Xu, Norell, Wang, Makovicky and Wu, 2002. A basal troodontid from the Early Cretaceous of China. Nature. 415, 780-784.
Not redescribed. Redescribed in Xu's (2002) unpublished thesis, and White (2009) briefly described the metatarsus. We've also had another partial skull described by Yin et al. (2018), and an endocast described by Yu et al. (2024).

Archaeornithoides
Elzanowski and Wellnhofer, 1992. A new link between theropods and birds from the Cretaceous of Mongolia. Nature. 359, 821-823.
Elzanowski and Wellnhofer, 1993. Skull of Archaeornithoides from the Upper Cretaceous of Mongolia. American Journal of Science. 293-A, 235-252.

Buitreraptor
Makovicky, Apesteguía and Agnolín, 2005. The earliest dromaeosaurid theropod from South America. Nature. 437, 1007-1011.
Not redescribed. Gianechini et al. have really knocked this one out of the park-
Gianechini, Makovicky and Apesteguia, 2011. The teeth of the unenlagiine theropod Buitreraptor from the Cretaceous of Patagonia, Argentina, and the unusual dentition of the Gondwanan dromaeosaurids. Acta Palaeontologica Polonica. 56(2), 279-290.
Gianechini, Makovicky and Apesteguıa, 2017. The cranial osteology of Buitreraptor gonzalezorum Makovicky, Apesteguıa, and Agnolın, 2005 (Theropoda, Dromaeosauridae), from the Late Cretaceous of Patagonia, Argentina. Journal of Vertebrate Paleontology. e1255639.
Gianechini, Makovicky, Apesteguia and Cerda, 2018. Postcranial skeletal anatomy of the holotype and referred specimens of Buitreraptor gonzalezorum Makovicky, Apesteguia and Agnolin 2005 (Theropoda, Dromaeosauridae), from the Late Cretaceous of Patagonia. PeerJ. 6:e4558.
Motta, Brisson Egli and Novas, 2018 (online, 2017). Tail anatomy of Buitreraptor gonzalezorum (Theropoda, Unenlagiidae) and comparisons with other basal paravians. Cretaceous Research. 83, 168-181.
Plus we have Novas et al. (2018; online 2017) on a referred specimen.

Unenlagia
Novas and Puerta, 1997. New evidence concerning avian origins from the Late Cretaceous of Patagonia. Nature. 387: 390-392.
Not redescribed except the ilium by Novas (2004).
Novas, Agnolin, Motta and Egli, 2021. Osteology of Unenlagia comahuensis (Theropoda, Paraves, Unenlagiidae) from the Late Cretaceous of Patagonia. The Anatomical Record. 304(12), 2741-2788.
Gianechini and Zurriaguz, 2021. Vertebral pneumaticity of the paravian theropod Unenlagia comahuensis, from the Upper Cretaceous of Patagonia, Argentina. Cretaceous Research. 127, 104925.

Sinornithosaurus
Xu, Wang and Wu, 1999. A dromaeosaurid dinosaur with filamentous integument from the Yixian Formation of China. Nature. 401, 262-266.
Redescribed in Xu's (2002) unpublished thesis. Not redescribed except for The skull (Xu and Wu, 2001), pes (Xu and Wang, 2000), and feathers (Xu et al., 2001) have been published. Of course S. haoiana and NGMC 91 may be synonymous, but these have not been described in detail, which if it is eventually done may enable us to judge this synonymy better.

Microraptor
Xu, Zhou and Wang, 2000. The smallest known non-avian theropod dinosaur. Nature, 408, 705-708.
The holotype has not been redescribed, though Redescribed in Xu's (2002) unpublished thesis. Two other specimens were monographed (Hwang et al., 2002) in time for my prior post, and now we also have detailed descriptions of other specimens (Pei et al., 2014; Xu and Li, 2016; Grosmougin et al., 2025; Chotard et al., 2025; etc.).

Microraptor gui
Xu, Zhou, Wang, Kuang, Zhang and Du, 2003. Four-winged dinosaurs from China. Nature. 421, 335-340.
Not redescribed, though White (2009) briefly described the metatarsus. But in 2025 I'd argue it's not that important, as it's generally seen as a junior synonym of M. zhaoianus and plenty of specimens of that have been well described. I guess it is kinda insulting to be sunk before being described in detail.

Neuquenraptor
Novas and Pol, 2005. New evidence on deinonychosaurian dinosaurs from the Late Cretaceous of Patagonia. Nature. 433, 858-861.
Not redescribed.
Brissón Egli, Rolando Aranciaga, Agnolín and Novas, 2017. Osteology of the unenlagiid theropod Neuquenraptor argentinus from the Late Cretaceous of Patagonia. Acta Palaeontologica Polonica. 62(3), 549-562.

Epidexipteryx
Zhang, Zhou, Xu, Wang and Sullivan, 2008. A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers. Nature. 455, 1105-1108.
Not redescribed.

Jeholornis
Zhou and Zhang, 2002. A long-tailed, seed-eating bird from the Early Cretaceous of China. Nature. 418, 405-409.
The holotype is not redescribed. We have the description of J. palmapenis by O'Connor et al. (2012; online 2011), which I think is synonymous with the type species. Plus detailed descriptions of other specimens' skull (Hu et al., 2022) and sternal ribs (Zheng et al., 2020). 

Confuciusornis dui
Hou, Martin, Zhou, Feduccia and Zhang, 1999. A diapsid skull in a new species of the primitive bird Confuciusornis. Nature. 399, 679-682.
Not redescribed. And lost according to Marugán-Lobón et al. (2011). Is that worse than Microraptor gui? Getting lost before you can be described in detail? Maybe we shouldn't give any more theropods _ui as a species name.

Enantiornis
Walker, 1981. New subclass of birds from the Cretaceous of South America. Nature. 292, 51-53.
Not redescribed.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.

Vorona
Forster, Chiappe, Sampson, Krause, 1996. The first Cretaceous bird from Madagascar. Nature. 382, 532-534.
Forster, Chiappe, Krause and Sampson, 2002. Vorona berivotrensis, a primitive bird from the Late Cretaceous of Madagascar. 268-280. In Chiappe and Witmer (eds.). Mesozoic Birds: Above the Heads of Dinosaurs. University of California Press, Berkeley, Los Angeles, London.

Eoalulavis
Sanz, Chiappe, Perez-Moreno, Buscalioni, Moratalla, Ortega and Poyato-Ariza, 1996. An Early Cretaceous bird from Spain and its implications for the evolution of avian flight. Nature. 382, 442-445.
Sanz, Pérez-Moreno, Chiappe and Buscalioni, 2002. The Birds from the Lower Cretaceous of Las Hoyas (Privince of Cuenca, Spain). pp 209-229. In Chiappe and Witmer (eds.). Mesozoic Birds: Above the Heads of Dinosaurs. University of California Press, Berkeley, Los Angeles, London.

Nanantius
Molnar, 1986. An enantiornithine bird from the Lower Cretaceous of Queensland, Australia. Nature 322 736-738.
Not redescribed. And apparently lost (O'Connor, 2009), so there's a second such taxon.

Apsaravis
Norell and Clarke, 2001. Fossil that fills a critical gap in avian evolution. Nature. 409, 181-184.
Clarke and Norell, 2002. The morphology and phylogenetic position of Apsaravis ukhaana from the Late Cretaceous of Mongolia. American Museum Novitates. 3387, 1-46.



So that's Nature, but what about Science?

Tawa
Nesbitt, Smith, Irmis, Turner, Downs and Norell, 2009. A complete skeleton of a Late Triassic saurischian and the early evolution of dinosaurs. Science. 326, 1530-1533.
Not redescribed fully, though Bradley et al. (2020; as 2019) did describe the sternals and Burch's (2013) unpublished thesis described the pectoral girdle and forelimb. There have been a lot of papers on isolated limb elements, and Burch (2014) on the forelimb musculature, but no osteology.

Cryolophosaurus
Hammer and Hickerson, 1994. A crested theropod dinosaur from Antarctica. Science. 264, 828-830.
Smith, Makovicky, Hammer and Currie, 2007. Osteology of Cryolophosaurus ellioti (Dinosauria: Theropoda) from the Early Jurassic of Antarctica and implications for early theropod evolution. Zoological Journal of the Linnean Society. 151, 377-421.

Deltadromeus
Sereno, Dutheil, Iarochene, Larsson, Lyon, Magwene, Sidor, Varricchio and Wilson, 1996. Predatory dinosaurs from the Sahara and Late Cretaceous faunal differentiation. Science. 272(5264), 986-991.
Not redescribed, though apparently being worked on by Ibrahim. Ibrahim et al. (2020) figured parts of the pes.

Piatnitzkysaurus
Bonaparte, 1979. Dinosaurs: A Jurassic assembalge from Patagonia. Science. 205, 1377-1379
Bonaparte, 1986. Les Dinosaures (Carnosaures, Allosauridés, Sauropodes, Cétiosauridés) du Jurassique moyen de Cerro Cóndor (Chubut, Argentine). Annales de Paléontologie. Paris, France. 72, 247-289.
We also had...
Rauhut, 2004. Braincase structure of the Middle Jurassic theropod dinosaur Piatnitzkysaurus. Canadian Journal of Earth Science. 41(9), 1109-1122.
... and more recently...
Pradelli, Pol and Ezcurra, 2025. 
The appendicular osteology of the Early Jurassic theropod Piatnitzkysaurus floresi and its implications on the morphological disparity of non-coelurosaurian tetanurans. Zoological Journal of the Linnean Society. 203(1), zlae176.

Afrovenator
Sereno, Wilson, Larsson, Dutheil and Sues, 1994. Early Cretaceous dinosaurs from the Sahara. Science. 266, 267-271.
Not redescribed. The maxilla was figured by Carrano et al. (2012) and the teeth detailed in Hendrickx et al. (2015).

Suchomimus
Sereno, Beck, Dutheil, Gado, Larsson, Lyon, Marcot, Rauhut, Sadleir, Sidor, Varricchio, Wilson and Wilson, 1998. A long-snouted predatory dinosaur from Africa and the evolution of the spinosaurids. Science. 282(5392), 1298-1302.
Not redescribed. A furcula was described by Lipkin et al. (2007) and we'll get occasional line drawings in works like Samathi et al. (2021) and Isasmendi et al. (2024), but that's it. The referred skull roof is Eocarcharia (Kellemann et al., 2025).

Raptorex
Sereno, Tan, Brusatte, Kriegstein, Zhao and Cloward, 2009. Tyrannosaurid skeletal design first evolved at small body size. Science. 326(5951), 418-422.
Not redescribed, though the associated fish vertebra was re-evaluated (Newbrey et al., 2013; Kim et al., 2022) to be a Nemegt Formation osteoglossomorph, so it's not the basal Jehol taxon Sereno et al. described it as in any case.

Haplocheirus
Choiniere, Xu, Clark, Forster, Guo and Han, 2010. A basal alvarezsauroid theropod from the Early Late Jurassic of Xinjiang, China. Science. 327, 571-574.
Not redescribed. Redescribed in Choiniere's (2010) unpublished thesis. Skull redescribed in-
Choiniere, Clark, Norell and Xu, 2014. Cranial osteology of Haplocheirus sollers Choiniere et al., 2010 (Theropoda: Alvarezsauroidea). American Museum Novitates. 3816, 44 pp.

Mahakala
Turner, Pol, Clarke, Ericson and Norell, 2007. A basal dromaeosaurid and size evolution preceding avian flight. Science. 317, 1378-1381.
Not redescribed. Turner, Pol and Norell, 2011. Anatomy of Mahakala omnogovae (Theropoda: Dromaeosauridae), Tögrögiin Shiree, Mongolia. American Museum Novitates. 3722, 66 pp.

Rahonavis
Forster, Sampson, Chiappe and Krause, 1998. The theropod ancestry of birds: New evidence from the Late Cretaceous of Madagascar. Science. 279, 1915-1919.
Not redescribed. Forster, O'Connor, Chiappe and Turner, 2020. The osteology of the Late Cretaceous paravian Rahonavis ostromi from Madagascar. Palaeontologia Electronica. 23(2):a31.

Protopteryx
Zhang and Zhou, 2000. A primitive enantiornithine bird and the origin of feathers. Science. 290, 1955-1959.
Not redescribed. New specimens have been described in detail though (Chiappe et al., 2020, online 2019; O'Connor et al., 2020).

Sinornis
Sereno and Rao, 1992. Early evolution of avian flight and perching: New evidence from Lower Cretaceous of China. Science. 255, 845-848.
Sereno, Rao and Li, 2002. Sinornis santensis (Aves: Enantiornithes) from the Early Cretaceous of Northeastern China. pp 184-208. In Chiappe and Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University of California Press, Berkeley, Los Angeles, London.
Honestly, it's a pretty bad redescription, with only the manus, pelvis and pes illustrated, but I'll count it as I did previously.


The 2010 post ended with "So, of all 33 theropods described in Nature, 25 (76%) have yet to be fully described in a published work.  Of all 11 theropods described in Science, 8 (73%) have yet to be fully described.  So in total, 75% haven't been redescribed."

Taken literally, of the 35 theropods described in Nature by 2010, 18 (51%) have yet to have their type specimens fully described in published literature. Of all 12 theropods described in Science by 2010, 7 (58%) have yet to be fully described. So in total, 53% haven't been redescribed.

It's an improvement of 22% over 15 years, which is better than nothing. But there's a more encouraging way to look at this. Due to technological advancements, theses are as easy to circulate as peer reviewed papers anymore, and when's the last time you saw the contents of a thesis actually change due to peer review? Offhand I'd say maybe 25 years ago.  So what's our ratio of taxa whose types haven't even been redescribed in a thesis? Only 18 (I'm counting Pelecanimimus) out of 47, so 38%. And a third of those have partial redescriptions out.


So going into 2026, what do we need? In an admittedly biased order of what I would like most first, I would say we need osteologies of the following that don't have an obvious group/person working on them- Dilong, Gigantoraptor, Jeholornis, Epidexipteryx, Tawa, Afrovenator, Mei, Suchomimus and Giganotosaurus. Half of those are at the IVPP, just sayin'.

If anyone knows that taxa on this post are being worked on my somebody I didn't mention, please chime in!