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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.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:
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
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
| `--+--Eudimorphodon ranzii
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
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,
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
| | `--Nyctosaurus
| `--+--Germanodactylus cristatus
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
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
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
(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.
Website (The Pterosauria): http://www.archosauria.org/pterosauria/
Dinosauricon Art Gallery: http://dino.lm.com/artists/display.php?name=mike