Saturday, October 10, 2015

The Compact Thescelosaurus

National Fossil Day is this Wednesday, October 14th. The 16th birthday of Thescelosaurus would have been last Wednesday, October 7th. In honor of both, here is The Compact Thescelosaurus, a sortable spreadsheet of basic information on classic (non-avian) dinosaur species, minus names that have not been formally described. I began working on it shortly after I decided to end the website; I still wanted the information to be available, but I also wanted something that was lower-maintenance, and more flexible to edit. This is what I came up with. The other nice thing about it was that I updated a number of things, which I can now use to clean up my original files and perhaps make them available as pdfs, for people who miss the dry commentary and the nomina nuda. This wouldn't happen for several more months, though. Anyway, here's a short user guide to the spreadsheet below the jump, column by column. If someone wants to use the format for some other group, they are free to do so. Otherwise, have fun!

[A quick note, 2015-10-12: I've received a couple of inquiries about being added as editors. I appreciate the interest, but at this time, I'd prefer to keep this project under one person. Feel free to send corrections and other information, though! (I consider many aspects of taxonomy to be matters of judgement, so we many have to agree to disagree on those matters.)]

Column A: scaffolding for maintenance. It also approximates the order the taxa were in on the Thescelosaurus web pages, so you can also use the numbers to navigate that way.

Columns B and C, Genus and Species: these two are self-explanatory. For species that either do not appear to belong to the genus they are currently assigned to, or are assigned to a dubious genus and are not the type species, the genus is given in quotes. Also, dubious species are assigned to their original genus, so for example Tanystrosuchus posthumus is listed under "Tanystropheus" posthumus. These unaccepted post hoc genera like Tanystrosuchus are listed in Column Y, with their authority and year. The columns up to C are frozen for convenience.

Column D, Status: this column is used to identify dubious and potentially dubious species. I tend to be conservative about designating something dubious.

Column E, Authority: this column lists the authors of the publication that named the species. Diacritical marks, hyphens, and accents may vary. For species moved to existing genera, year (Column F) and authority are for the original combination, because I wasn't in the position of tracking down the first usage of a given combination. The original combination is in Column AA. For species given new genera, the year and authority are for the new combination, and as before the original combination is given in Column AA.

Column F, Year: self-explanatory (see also above under Column E). In a few cases, a name was available online a year or two before an actual publication in hardcopy form, and these are noted with pop-out comments.

Columns G and H, Period and Age: In these columns we get information like "Cretaceous (Late)" and "Maastrichtian", respectively. For cases where a species spans multiple periods and ages, the oldest is listed first, then the next oldest, and so on. This is counter-intuitive from a geologic point of view, because you might be expecting to see youngest to oldest descending, but *is* intuitive if you are reading top to bottom, because you will then proceed from oldest to youngest in order. If it's really confusing, I'll change it. In most cases, all records from a specific formation (Column L) will have approximately the same data, but some vary, such as the Cedar Mountain Formation. This is an example of a formation with multiple subdivisions of substantially different ages. In some cases, the Age is not known, or is so poorly defined as to be a pointless category to list. The Lianmuqin Formation is one offender, its age given as Valanginian?–Albian. This might as well be flat-out Early Cretaceous. Many formations have poorly defined ages. I tried my best to find recent estimates, but in many cases they are still fuzzy. Some have radiometric ages that are commonly assigned to a particular geologic age based on timing that is now outdated (e.g. a radiometric date that once fell in the Barremian now falls in the Aptian; see also the tweak of the Campanian–Maastrichtian boundary); I have taken this into account. I do not put much stock in detailed biostratigraphy using dinosaurs, because too often we're dealing with only, say, an isolated bone from the Colorful Local Landmark Name Formation that looks something like the same bone of Species X from the Damnably Tough Quartz-Cemented Quartz Sandstone, and the DTQ-CQS is poorly dated in the first place. Wishful thinking in, wishful thinking out. I expect that we'll learn some interesting things once we finally get radiometric dates from a few more of these formations.

Columns I, J, and K, Landmass, Nation, State/Province/Etc.: these columns handle geography. A few nations decided to be difficult and changed their internal divisions in the years since the Dinosaur Distribution chapter of the 2004 edition of The Dinosauria. France was all right, because it's getting larger regions. Madagascar and Portugal were not so easy, Madagascar because it went from large provinces to smaller regions, and Portugal because there were too many systems to choose from. In the end, for these two nations I went with the old divisions used in The Dinosauria (2004). In some cases, a species is known from more than one nation, national subdivision, or formation (Column L). In these cases, the place or formation where the holotype (the name-bearing specimen) came from comes first, and the rest follow alphabetically. If needed, states/provinces/etc. and formations are also followed by an additional identifier in parentheses, the first letter of the nation (for states/provinces/etc.) or the state/province/etc. (for formations).

Column L, Formation: the geologic unit a fossil was found in. I stuck with the formation level except for a couple of cases where the rocks in question had not been divided into formations. I did not go down to members. You may see some differences between the spreadsheet and other sources, especially if a formation's name has changed since something was named, or if a specimen was later found to have come from a different formation. Portugal again proved to be difficult; apparently everyone working in coastal Portugal has their own system for divvying up the Upper Jurassic rocks.

Columns M through X: these columns can be used for sorting by clades. Column M is the smallest higher-level clade for a given species, hence the "Clade of Convenience". The others go from Saurischia/Ornithischia and then on down. I tried to pick clades that seemed most useful for somebody sorting, but I did have to cap the columns at a certain point, because otherwise we could go on all day with finer and finer clades.

Column Y, Other Generic Names Not Covered: there are a few generic assignments that were not included under other columns, but which needed to be addressed. Generally speaking, these are generic names applied to dubious species, which I did not use. There are a few other categories: a couple where a species was moved from one genus to a new genus, but the new genus proved to be preoccupied ("Monoclonius" belli to Protorosaurus belli to Chasmosaurus belli); a couple where a species began under one genus, was given a new genus, and later was moved to a third, existing genus ("Claosaurus" annectens to Anatosaurus annectens to Edmontosaurus annectens); and a couple where a new genus name was given because it was mistakenly thought that the old genus name was preoccupied (Eucentrosaurus for Centrosaurus).

Column Z, Possible Synonyms: these synonyms may be at the genus or species level, and are only included for species that would be the junior synonym.

Column AA, Notes: everything else. The main contents are original names and names included as synonyms. I opted to not make separate entries for species regarded as synonyms, but if there is interest it would not be difficult to add them (the subjective synonyms, that is; nuts to the objective synonyms). There are also a few comments on other topics. Albert-FĂ©lix de Lapparent had a habit of taking a group of fossils collected from multiple localities, calling them a new species, and not designating a type specimen. Protip: this is never helpful.

12 comments:

  1. Here is my database more than 2600 species excel file
    https://www.sendspace.com/file/a56ct4

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  2. Also on the my page in facebook - Tribute to Dinosaurs are updates

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  3. I don't know if you will see this, because this is a 5 month old blog post, but I figured I might as well try it. I didn't want to post it anywhere else because I figured it would just be spam.

    So, I was looking around the Theropod Database, and the mega-encyclopedia The Dinosauria, and I came across a few things that aren't in the Thescelosaurus.

    First is Velocipes guerichi. Was this supposed theropod left out on purpose? I just noticed it was not in your database, and wondered if it was a mistake or you left out because it is too scrappy and not certainly a dinosaur. Though I thought it would be in Dinosauromorpha? at least.

    Then I have three other dubious species that aren't in the database that I found. "Plateosaurus" ornatus, "Plateosaurus" elizae, and "Megalosaurus" obtusus. Again were these left out on purpose? Or did you just forget about them?

    The Compact Thescelosaurus is my favorite place to get some quick basic information on pretty much any dinosaur that has been named. Paleofile is too cluttered and outdated and the Theropod Database only covers theropods, so Thescelosaurus is my favorite. Keep up the great work!

    Oh and "Stegosaurus" longispinus was finally described by someone who isn't Ulansky.

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    1. Thank you for your comments!

      I see that Velocipes should indeed be listed, so I'll add that momentarily. The other three dubious species you mentioned I have as nondinosaurian. I'll take care of Alcovasaurus shortly, too.

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    2. Ah, thanks for that clarification! Thescelosaurus just gets better!

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  4. You added Choristodera! Why? I have no objection to it at all, its awesome, but why? Do you plan to do more groups as well (particularly Pterosauria)?

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    1. I'm working on a post right now which will mention the new sheet. Yes, I do want to add more groups, and yes, Pterosauria is near the top of the queue!

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