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Re: a closer look at Lü and Ji 2006

Let's start with the basal taxon: Anurognathidae. It would be better to start with some Triassic taxon, I would think. So there's the first red flag.

Strangely the anurognathidae are not a sister taxon (to the exclusion of all other pteros) to Dimorphodon + Preondactylus (which form a clade of their own when properly reconstructed (and a tip of the hat to Dr. Unwin again who predicted this many years ago)). Here both are successively basal to Sordes, a mistake I also put into print many years ago. It's easy enough to do given too few taxa and characters. Strangely that forces Eudimorphodon three steps higher in the cladogram, higher than Scaphognathus and Dorygnathus. That's another red flag.

The inclusion of Peteinosaurus(?) Ex3359 and MCSNB 8950 would help this portion of the cladogram.

When MPUM 6009 and Austriadactylus are included, they attract Eudimorpodon ranzii and the other Eudimorphodons abit lower on the cladogram, keeping the Triassic forms at the base, morphologically and chronologically where they belong. In this way, the various Mid Jurassic Campylognathoides, which are strongly attracted to Eudimorphodon, forms a separate branch which, in time, begets the various late Jurassic Rhamphorhynchus species, but not without a size squeeze during the transition. All forms blending and in chronological order.
Nothing wrong here, except where Campylognathoides leads to Rhamphorhynchus and where Preondactylus and Dimorphodon form a single clade. For a reference, my analyses tend to indicate the following for the classification of non-pterodactyloid pterosaurs:
`--+--+--"Eudimorhpodon" rosenfeldi
| `--+--Austriadactylus
| `--+--Eudimorphodon ranzii
| `--Campylognathoides
| `--Scaphognathus
| `--+--Rhamphorhynchus
| `--"Odontorhynchus"
A growth series. JVP 2 or 3 years ago, bone histology: there is such a thing as immature *Rhamphorhynchus* in the fossil record.
True, but Bennett is also a fanatic lumper. There appear to be three different forms, especially seen in lower jaw morphology, one includes R. muensteri and R.gemmingi, a second includes R. intermedius, R. longiceps, and Wellnhofer's R. sp. (the juvenile specimen), and the third includes only R. longicaudus. It seems that while R. longicaudus specimens may be juveniles, they are not juveniles of any other species since juveniles of the other morphs have a more strongly curved and pointed lower jaw. Members of the R. longiceps morph are much more robust (this applies to juveniles also) while members of the R. muensteri form are more gracile. It appears that Bennett made a mistake in failing to take morphology and a particular hatchling specimen (R. sp.) into account and instead relied heavily on statistics. The information otherwise suggests that some species may be based on juveniles of other species, but they are not necessarily all members of a single species.
When six Dorygnathus are used in a cladogram, instead of one as in prior works, you find that the short-toothed Donau specimen is basal to the more derived wicked-toothed forms, and that Sordes is its sister (more about Sordes and Co. later).

As HP Marjanovic stated earlier, this specimen is likely a juvenile. Also, in my experience, it is a very bad idea to base anything off of x-ray photos.

The Dorygnathus known more specifically by their numbers as SMNS 55886 and R 156 are basal to a branch that includes in order: D. purdoni (another tip of the hat to Dr. Unwin for that) and Angustinaripterus, long touted as a good transitional form between 'rhamphorhynchoids' and 'pterodactyloids' but strangely missing from this analysis, and as I look back -- all other recent analyses. What happened to our star quarterback? Put him back into the game and see what happens!

My analysis indicates that Parapsicephalus (along with the very similar Cacibupteryx) is a transitional form between Scaphognathids and Rhamphorhynchids (which include Dorygnathus). Angustinaripterus is a sister taxon to the clade containing Pterorhynchus and the Pterodactyloidea. I've recently been shown photos of the skull of Pterorhynchus and the characters it shows are strongly pterodactyloid. The x-ray photos published in the [bad] description are inadequate at the least in illustrating this similarity.

Of course, this is my analysis and it includes many more taxa and characters than does that of Lü and Ji. I haven't tried to enter Perapsicephalus, Angustinaripterus, and Pterorhynchus into their matrix, not yet...

Strangely, Lu [sic] and Ji place the horizontal-toothed pteros with sharp-snouted Germanodactylus, which seems as unlikely as pairing a spoonbill with a woodpecker. There are better matches out there. They just need to be included.

This is because Lü and Ji based their character list largely off of Kellner, 2003 with only a few modifications. I suspect Kellner may be excluding characters from his list in order to support his "Archaeopterodactyloidea" which basically includes ctenochasmatids, cycnorhamphids, and "germanodactylids," essentially all basal pterodactyloids, and places them in a clade seperate from the ornithocheiroids and tapejaroids. My analysis is closer to Unwin's in this respect.

   |  `--+--Lonchodectes
   |     `--+--Cycnorhamphidae
   |        `--Ctenochasmatidae
      |  `--+--Istiodactylidae
      |     `--+--Boreopterus
      |        `--+--+--Pteranodontidae
      |           |  `--Nyctosaurus
      |           `--Ornithocheiridae
      `--+--+--"Daitingopterus" rhamphastinus
         |  `--+--Germanodactylus cristatus
         |     `--+--Dsungaripteridae
         |        `--+--Tapejaridae
         |           `--+--Tupuxuaridae
         |              `--Azhdarchidae
Pterorhynchus is strongly attracted to Sordes, but so far has left no
sister taxa. Where is Pterorhynchus in these latest studies? Nowhere.
Aye, see above.

Scaphognathus is also strongly attracted to Sordes and is basal to all remaining pterosaurs. If one includes all three (?) well-known Scaphognathus specimens (which Lu and Ji do not), one finds that S. crassirostris and SMNS 59395 are basal among them. The third named specimen, the Maxberg specimen, continues a size squeeze that continues even further with an even tinier pterosaur, TM 13104 and further up the line, G-mu 10157, both with slightly elongated metacarpals. Afterwhich one gets a big size jump with cycnorhamphids and ornithochierids (they have the same strange feet among other characters) emerging from the genetic pool. And so a third branch of 'pterodactyloid'- grade pterosaurs emerges with a morphological spectral blend from a 'rhamphorhynchoid' base. Again, remember, this doesn't happen in a cladogram with tiny pterosaur exclusion. In other cladograms you get confusion and 34,000+ MPTs.
Nothing wrong about Sordes and Scaphognathus being realted.
As for different branches of "pterodactyloid grade" pterosaurs descending from a "rhamphorhynchoid base," that seems unlikely. Here I reiterate HP Marjanovic's question, "What is your criterion for declaring a pterosaur adult?" If one were to construct a cladogram of homonids including babies, young chimpanzees and humans would form a clade separate of the adults with adult humans perhaps being closer to this "juvenile clade" than chimpanzees and with adult humans closer to juvenile chimpanzees than to juvenile humans. While this case would be different from the above mentioned analysis, it demonstrates how including individuals of the same species but of a different developmental stage would dramatically change the outcome.
I think my analysis sufficiently demonstrates pterosaur relationships in a "morphological blend" and gives only a hundredth of the number of MPTs given above, but it has over 120 characters and over 80 taxa, far more than Unwin's or Kellner's analyses.

Strongly attracted to No. 9 is AMNH 1942, which has the same size torso, wings and legs, but a longer neck and rostrum. AMNH 1942 is also known as Pterodactylus and it is basal to the other Pterodactylus forms we all know and love, including the big one, Diopecephalus. Lu [sic] and Ji place two Pterodactylus between Beipiaopterus and Eosipterus. In this case, the addition of No. 9, AMNH 1942 and other pteros would provide the realignment.
Well, Pterodactylus kochi and P. antiquus should fall together in an analysis, but P. micronyx may be a juvenile Diopecephalus or Gnathosaurus and P. elegans is a juvenile Ctenochasma. In my analysis, Eosipterus is a sister taxon to the Lonchodectids, but the Lonchodectids are a notoriously problematic group, so that may not mean much.
Another sister to No. 9 is No. 12 which has a longer and noticeably sharper rostrum. It begets all of the sharp-nosed pteros, starting with various versions of Germanodactylus (including Eosipterus). Lu [sic] and Ji show Eosipterus to be a sister taxon to Germanodactylus (which is good) and also to the ctenochasmatids + cycnorhamphids (which is bad = doesn't make sense). See above for better matchups.
Ummm... Diopecephalus, Feilongus, Liaoxipterus?

As mentioned earlier, the addition of more tiny pteros and more pteros in general pulls Quetzalcoatlus, Zhejiangopterus, Jidapterus and Chaoyangopterus away from Eopteranodon + Eoazhdarcho + Azhdarcho, which form a separate clade with a convergent elongated cervical series. The flat versus pointed shapes of the dentaries are diagnostic, as are a whole raft of other post-cranial characters.
Again, adding juveniles will only cause confusion.

Lu [sic] and Ji's family tree of tapejarids and dsungaripterids has problems (but that's because Quetzalcoatlus and Zhejiangopterus are incorrectly basal here). The dsungaripterids should branch off first (if germanodactylids are basal, as they should be), followed by the monophyletic tapejarids.
Yes, the consensus tree is... frightening, and the problems are not just limited to the tapejaroids. I agree with the fact that these problems are due to a lack of characters and taxa.

It just takes more taxa and more characters and all the confusion melts away.
More taxa and characters, yes, but as stated above and by Marjanovic, adding juveniles will only lead to confusion. I'd say it is a good idea (if one wants to include juveniles) to do as HP Marjanovic said and code ontogeny-related characters as unknown for juvenile individuals.

Whether you want to call tiny pterosaurs tiny adults or tiny babies, it doesn't matter to me what your religion is. The fact of the matter is, when tiny pteros are included in a matrix relationships between sister taxa become clarified, changes between sister taxa take on a spectral blend and you get a single tree with crazy derived forms at the tips of bushy branches and the metaphorical 'plain brown sparrows' forming the backbone of the chain. Sharp beaks go with sharp beaks. Horizontal teeth go with horizontal teeth. Small pectoral complexes go with... well, you get the picture.
Sure, the results may make sense, in fact, they are very likely to make sense one way or another, but they may not reflect the true evolutionary relationships.

(Lu and Lü are not pronounced the same.)
Just for the sake of pronunciation, u in Pinyin is pronounced (IPA) [u], which is equivalent to the English sound for "oo", ü is pronounced [y], which is approximately equivalent to saying the English sound for "ee" with rounded lips.

Mike Hanson
Email: mhanson54@comcast.net
Website (The Pterosauria): http://www.archosauria.org/pterosauria/
Dinosauricon Art Gallery: http://dino.lm.com/artists/display.php?name=mike