Thursday, January 3, 2013

Martyniuk's (2012) new definitions and clades

Martyniuk's "A Field Guide to Mesozoic Birds and Other Winged Dinosaurs" is out, and while most of it is in the form of a popular field guide, it's also filled with a ton of new phylogenetic definitions and some new taxa.  A review of the entire book is in the pipeline, but let's look at this one section of it today.

Aviremigia is officially proposed (note Gauthier and de Quieroz only conditionally proposed it), though contra Martyniuk, the latter would near certainly have used Vultur not Passer, as in all of their bird-based clades.  Since we still don't know how far towards the base of Maniraptoriformes remiges and retrices extend due to possible taphonomic effects, proposing this apomorphy-based clade still seems premature.

We get a definition for Chuniaoae as the oviraptorosaur+paravian group (in most topologies), so we finally have a name for that.  I can't help but think my discussion of this name on the Database is responsible, which I regret a bit as it is such a terrible name and wasn't intended to be so inclusive (it was named as an avialan clade including Caudipteryx+birds).

Caenagnathiformes is defined, and while it is older than Oviraptorosauria, there are no rules saying it must have precedence, and Oviraptorosauria has had basically universal acceptance.  I can't see this being adopted, so I have to wonder why it was proposed.

Caenagnathinae is defined as (Caenagnathus collinsi < Oviraptor philoceratops, Avimimus portentosus), but is rather useless in a topology like mine where Avimimus is a caenagnathid. Ditto for Avimimidae being (Avimimus portentosus < Oviraptor philoceratops, Elmisaurus rarus, Caenagnathus collinsi). Elmisaurinae is used in the next section as sister to Caenagnathinae, but is never defined.  Note that position would make Elmisaurus a caenagnathine in Martyniuk's phylogeny.

Ornithes is proposed for Aves sensu Chiappe- (Archaeopteryx lithographica + Passer domesticus), which is nice to have.

We get a definition for Nicholson's 1878 name Saurornithes (Archaeopteryx lithographica < Passer domesticus), but I pretty strongly disagree with this. It's a synonym of the earlier named Archaeopterygidae (1871; using Xu et al.'s 2011 definition) if Archaeopteryx is avialan or basal to Eumaniraptora; or if Archaeopteryx is deinonychosaurian, it's a synonym of that clade. Though named far before Deinonychosauria, it's not nearly as widely used or well known, and if priority is what matters, why not use the even earlier Sauriurae (1866), which is also better known and used due to BANDITs?

Ornithodesmiformes (Ornithodesmus cluniculus, Dromaeosaurus albertensis, Troodon formosus < Archaeopteryx lithographica) is another name I'm unhappy with.  While I agree Ornithodesmus is probably a dromaeosaurid and Ornithodesmidae has priority over Dromaeosauridae, the need for linked subclades doesn't exist in Phylocode and the ICZN doesn't cover taxa higher than family level.  It's potentially useful when we have basal deinonychosaurs, and Ornithodesmus probably is a member, but there are more secure names that could have been chosen.

I DO like Troodontinae (Troodon formosus + Saurornithoides mongoliensis) though, which has been needed for a while.  Problematically, Saurornithoidinae is listed as a taxon of equal rank in the next section, though it would be a synonym and has never been proposed before.

Ornithodesmidae is used in place of Dromaeosauridae as it was named earlier and defined as (Ornithodesmus cluniculus < Archaeopteryx lithographica, Passer domesticus, Paronychodon lacustris, Pterodactylus antiquus). I'd guess Paronychodon stands in for Troodon as the latter was not named in 1913 when Ornithodesmidae was proposed. The ICZN does give Ornithodesmidae priority, but as it is never used (and not everyone accepts Ornithodesmus is a dromaeosaurid, though their published reasons have been invalid) I would rather the ICZN be petitioned to sink it.

Microraptorinae is defined as a less inclusive microraptorian clade- (Microraptor zhaoianus < Sinornithosaurus millenii, Dromaeosaurus albertensis).  It's useful if Cryptovolans is separate, but otherwise not so much until microraptorian phylogeny is better understood. Also note Turner et al. (2012) already defined this clade as a junior synonym of Microraptoria.

Itemiridae (1976) is defined as (Itemirus medullaris < Dromaeosaurus albertensis, Stenonychosaurus inequalis, Tyrannosaurus rex), which is seemingly to replace Velociraptorinae from 1983. Indeed, it is only referred to in the text as 'itemerine', and Itemirinae is proposed in the next section (which makes that a new name). I'm at a loss why Stenonychosaurus was used this time, as Troodon was named long beforehand and the fact the Stenonychosaurus holotype preserves a braincase wouldn't seem to matter for any part of Phylocode. I think using Itemiridae/inae is a bad choice, as only one analysis has placed Itemirus in Velociraptorinae, and this was only based on one character (basioccipital tubera with distinct, ovoid depressions on the caudal surface).  There are other characters that contradict this, and Miyashita (2011) even found it as a tyrannosauroid in his analysis.

Kudos to Martyniuk for recognizing Omnivoropterygidae/-iformes has priority over Sapeornithidae/-iformes.  Yet his solution puts us in an awkward situation, as he defines Omnivoropteryiformes, but ignores the family (though only the family is used in his taxonomic table).  And yet the family (as Sapeornithidae) is used more often than the order by authors, the ICZN doesn't recognize priority of order-level taxa (so really only the family's priority is mandated), and this is the first definition ever applied to any of these groups AFAIK. So if we want to follow the defined clade name, we have to use a synonym which is barely used AND non-mandated, and not of the same level as the term most authors use. Ack.

I like Martyniuk defining Confuciusornithiformes as (Confuciusornis sanctus < Enantiornis leali, Passer domesticus), since Confuciusornithidae has been defined as (Confuciusornis sanctus + Changchengornis hengdaoziensis) by Chiappe et al. (1999). Other authors (e.g. Zhang et al., 2008) have largely ignored the definition.

Martyniuk defines a LOT of enantiornithine clades, though I don't think our understanding of enantiornithine phylogeny justifies this yet.  For instance, using O'Connor and Zhou's (in press) topology, Iberomesornithiformes, Eoenantiornithiformes and Eoenantiornithidae are all monotypic, Longipterygiformes includes Longipteryx and the probably synonymous Boluochia, and Cathayornithiformes includes Neuquenornis, Eoenantiornis, Conornis, Eocathayornis, Liaoningornis and Eoalulavis in addition to Cathayornis.  I do like that he uses Cau and Anduini's definition of Avisauridae for Avisauroidea, since Avisauridae had been previously defined differently.

Patagopterygiformes is defined, which isn't too useful as no taxa have been found in published analyses to clade with Patagopteryx.  Sure Alamitornis, Kuszholia and Gargantuavis have been proposed, but surely it's better to need a clade before you define it.

Defining Chaoyangiformes is about as useful as those enantiornithine clades, since Chaoyangia's position among 'euornithines' hasn't been established.

Defining Songlingornithidae as (Songlingornis linghensis < Chaoyangia beishanensis, Passer domesticus) works as long as Chaoyangia isn't one, which it seems not to be.  However, defining Yanornithiformes as (Yanornis martini < Passer domesticus) seems like it should be a low priority until there's good evidence Yanornis isn't a songlingornithid.

Similarly, defining Ambiortiformes is nice (Ambiortus dementjevi < Passer domesticus), but then defining Apsaraviformes as a junior synonym in his own topology (Apsaravis ukhaana < Passer domesticus) is just odd.

Martyniuk defines a misspelled Odontolcae (as Odontoclae) as (teeth set in grooves as in Hesperornis regalis). Well, enantiornithines, Yanornis and outgroup avialans have teeth set in sockets (as may Gansus), but Hesperornis and Ichthyornis have them set in grooves.  Aves lack teeth so are inapplicable, which leaves us uncertain where to apply the name, even if we knew the relationships between Hesperornithes, Ichthyornis and Aves, which we don't.  So why ressurrect a name originally idealized as what we call Hesperornithes (Ichthyornis was in Odontormae) and give it a definition which can't be applied to a specific node given our current information?

He defines Odontornithes as (Ichthyornis anceps, Hesperornis regalis < Passer domesticus), but doesn't actually support the clade.  Hmm.  As a nitpick, if Martyniuk's goal was to choose taxa known when the clade was named, I. anceps was still placed in Graculavus in 1873 when Odontodornithes was named, and was not recognized as an odontornithine at the time, so I would have chosen I. dispar.

Hesperornithiformes is defined as (Hesperornis regalis + Enaliornis barretti), which is basically identical in composition to the stem-based Hesperornithes in most(every?) published phylogeny.  Even worse, we don't know how Potamornis and Pasquaornis relate to Enaliornis, nor if the three species of Enaliornis form a clade exclusive of Hesperornis.  So Hesperornithiformes is quite unecessary at the moment.  The same could be said of Enaliornithidae (Enaliornis barretti < Hesperornis regalis).

Based on my phylogeny for hesperornithines, Brodavis (if it includes varneri) falls within Hesperornithidae, so Martyniuk's definition for Brodavidae (Brodavis americanus < Hesperornis regalis) is not only redundant with Brodavis but inside another family.

I like Hesperornithoidea for the (Baptornis advenus + Hesperornis regalis) clade, but I should note Schufeldt (1903) originally named it for more inclusive clade also including Enaliornis.

A definition for Baptornithidae is nice I suppose, but there are no definite members besides Baptornis advenus, so it's redundant currently.

A definition for Gansuiformes is also redundant at the moment.

We already have the older clade Ichthyornithes defined as (Ichthyornis dispar < Struthio camelus, Tinamus major, Vultur gryphus), why define the newer Ichthyornithiformes as (Ichthyornis anceps < Hesperornis regalis, Gansus yumenensis, Passer domesticus)?  I agree including Hesperornis as an external specifier is good, but why not just ammend the definition of Ichthyornithes?  Also, the type species Ichthyornis dispar should be used in a definition based on Ichthyornis, even if I. anceps is a senior synonym.

I have no issue with his new definition for Anseriformes.  Anatoidea should be based on Anas platyrhynchos though, not Anser anser.

The suggested definition for Gaviiformes (crown Gavia immer < Podiceps cristatus, Passer domesticus) would include all of Natatores, Gruiformes, Cuculidae, etc. under molecular phylogenies.

The definition for Charadriiformes (crown Charadrius hiaticula < Passer domesticus) might work, but might also include Natatores, Gruiformes, etc. as well.

So overall, we have some useful definitions (Chuniaoae, Ornithes, Troodontinae, Confuciusornithiformes, Songlingornithidae, Ambiortiformes, Hesperornithoidea), but a large number are currently redundant and some don't even define clades he thinks are valid or are synonyms of other clades he defines.  Others don't have a clear use, as phylogenies of relevent taxa are still in flux.  The emphasis on oldest names is admirable in a way (and I fully support action to either use or officially suppress them for family level taxa), but when not mandated by the ICZN it just causes confusion (following Martyniuk's logic, we would use Goniopoda for Theropoda, Opisthocoelia for Saurischia, etc.).  Martyniuk does do a good job defining most clades though, using eponymous genera and type species for most.

Stay tuned for my feelings on the rest of the book.

Reference- Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs. Vernon, New Jersey. Pan Aves. 189 pp.

10 comments:

  1. Thanks for the review Mickey! I figured this would be the most controversial section of the book but i think you're the first one who really got into it :) You note correctly that many of the definitions are monotypic or redundant, which I also noted in a few places in the text itself. The idea here was as a (possibly futile) hedge against future misuses or misapplications, basically preemptively trying to enforce priority. A similar philosophy was used when attempting to define the enantiornith clades--while we certainly have no real clue right now how those things are all related, I wanted to make sure the fist' names were preserved no matter how it shakes out. I also tried to anticipate future usability of the names, hence defining Omnivoropterygiformes but not Omnivoropterygidae (I reckon we'll eventually get more diversity in this clade, making the "order" level name tempting to use for the branch-based group and reserving the "family" level name for hypothetical node-based sub groups.

    As you imply, some of these are hedges, and I actually tried to define some historical names based on currently paraphyletic assemblages to self-destruct, i.e. Odontornithes. I tried to preserve original definitions whenever possible as noted in the intro to the appendix, hence weird situations like Ichthyornithes vs. Ichthyornithiformes (which I attempted to define in such a way that it would be valid if Odontornithes ever turned out to be real, but a junior synonym of Ichthyornithes otherwise).

    It's definitely a little quirky, and I know a lot of people will not follow my preference for older names with priority outside ICZN preview, but I took the opportunity to try and correct the twisted course naming Mesozoic avian taxa has been going down. If people insist on naming monotypic taxa on the premise that they may be required by unknown future diveristy, why not define them as well and let the chips fall as they may?

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  2. "Problematically, Saurornithoidinae is listed as a taxon of equal rank in the next section, though it would be a synonym and has never been proposed before."

    It was automatically proposed when Saurornithoididae was named (Barsbold 1974).

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  3. Chuniaoae, huh? Couldn't we think to use this as an opportunity to pick a more elegant, classical name? Like, something in Icelandic.

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  4. "I'd guess Paronychodon stands in for Troodon as the latter was not named in 1913 when Ornithodesmidae was proposed."

    What? Troodon was named in 1856.

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  5. Matt- That philosophy does make sense in a way, though it unfortunately will probably prove futile in my opinion, if for no other reason than your book isn't a traditional technical source. It's the opposite philosophy of Padian et al.'s (1999), but we are the new generation I suppose. I also like the concept of making sure the first names are supported, so we don't get another Segnosauria > Therizinosauria due to nothing more than social inertia. Though I note you didn't define some early enant names like Concornithidae (1996), Cuspirostrisornithidae (1997), Sinornithiformes (1997), Gobipterygidae/-iformes (1974) and Liaoningornithidae/-iformes (1996), and the latter two especially may prove useful. The preference for orders compared to families also makes sense the way you explain it, it just causes a bit of awkwardness to transition to.

    Mike- Well, yes. I should have said it was never explicitly proposed before.

    Brad- Do'h! Don't know how I managed to write that. Makes me extra curious why Paronychodon was used then.

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    1. I have to admit some of those were oversight: I was aware or had forgotten that those names had been coined. In the case of Gobipterygiformes, though, this was an intentional omission. I couldn't figure out a way to stick to my goal of using only taxa known at the time as specifiers without making it a synonym of Enantiornithes. One instance where I let personal preference for a well-established name trump strict priority I guess :)

      As for Paronychodon instead of Troodon, I think I must have had the same brain fart as you, Mickey! Checking my notes I do indeed have the wrong date down for Troodon (1932). I imagine I somehow used the date for Stenonychosaurus by mistake. Not that it would likely change the contents of the clade very much even if Ornithodesmus turned out to be a troodontid.

      Re: Goniopoda -- According to TTD itself, Cope originally used Goniopod for Lealaps and Megalosaurus, so if anything wouldn't this be a senior synonym of Orionides?

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    2. Also note Eoenantiornithidae (Longipteryx), Cathayornithiformes (Longipteryx), and Ichthyornithiformes (Gansus) don't only use taxa known at the time as specifiers. Is that a rule or recommendation in Phylocode btw?

      As for Goniopoda, you're assuming minimum inclusiveness. But as Cope found more theropods, he referred them to Goniopoda, even basal avepods like Coelophysis and ones that would be non-avepod theropods in modern usage like Anchisaurus (as Megadactylus) (Cope, 1887).

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  6. What if, following Matt's definition of Avisauroidea, it turns out as a subclade of his Avisauridae? This is what happens in the most recent iterations of my phylogeny. I'm not a fan of Linnean ranks, but suspect that most would disagree with taxonomies where a Clade-oidea results inside its own Clade-idae.
    This is why in 2008 I decided to emend Chiappe's definition of Avisauridae for a (probably) more stable definition anchored on Avisaurus only, avoiding to define a never used Avisauroidea.

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    1. I agree having Avisauroidea inside Avisauridae is distasteful, and I agree making your definition be Avisauroidea isn't the best choice. I suppose what I didn't like was that your definition of Avisauridae made it quite a different clade than Chiappe intended. Longipteryx wasn't known, of course, though it and Gobipteryx both fall outside of Avisauridae if included in Chiappe's analysis. But Sinornis can fall inside it- http://home.comcast.net/~eoraptor/Chiappe%201993.htm (bottom of page), so does not clearly fall outside the morphological concept Chiappe had for the family. If emmending Chiappe's definition, I would have went with (Avisaurus archibaldi + Neuquenornis volans <- Concornis lacustris, Gobipteryx minuta, Iberomesornis romerali). All three external specifiers were known in 1993, and all three fall outside Avisauridae when analyzed in his matrix, and if one's closer to Avisaurus than Neuquenornis the clade will self destruct.

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    2. Edit: my last iteration has produced Avisauridae nested into Avisauroidea.

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