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a closer look at Lu and Ji 2006
And yes, please forgive the typo of Li vs. Li (Ji). Thank you Dr. Unwin.
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
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
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). The Dorygnathus more
precisely known as SMNS 50164 has a tiny pterosaur as its sister
taxon, TM 10341. When this pterosaur is included (which it is not in
Lu and Ji 2006) not-so-tiny Beipiaopterus is strongly attracted to it
as are a number of other tiny pterosaurs, including SOS 2428, AMNH
1715 and Wellnhofer's No. 42. The last two tiny pteros are sister
taxa to SOS 2179 and Huanhepterus on one branch. On another sister
branch are a series of increasingly larger forms beginning with
Jidapterus and Chaoyangopterus and leading to Zhejiangopterus and
Quetzalcoatlus (but not Azhdarcho and Co. more about them later). So,
some pterodactyloid-grade pterosaurs show up on this branch, but the
rest do not.
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
Anyway, the wonderful Angustinaripterus with the garage door teeth
does lead, not surprisingly, to others with similar teeth and
everything else, Gnathosaurus and Ctenochasma + Pterodaustro, but not
without yet another phylogenetic size squeeze. And with that we have
our second branch of 'pterodactyloid' - grade pteros without
including all of them. Strangely, Lu 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.
Back to Sordes.
Pterorhynchus is strongly attracted to Sordes, but so far has left no
sister taxa. Where is Pterorhynchus in these latest studies? Nowhere.
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.
There is another pterosaur that is so strongly attracted to
Scaphognathus that, if not for its diminutive size and neotenous tail
(already on the wane in other Scaphognathus anyway) and its slightly
elongated metacarpus, it might have been named Scaphognathus sp.
That's the tiny pterosaur Wellnhofer named No. 9. Despite having a
short scaphognathine rostrum, it also has a slightly sharper rostrum.
And here begins the fourth and final branch of 'pterodactyloid' -
grade pterosaurs derived from rhamph-type ancestors.
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 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.
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
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.
It is difficult for me to understand how Germanodactylus can be so
far removed from (azhdarchids (not including Q. and Co.)) +
(nyctosaurs + pterandons)) + (tapejarids + dsungaripterids), but
that's how Lu and Ji show it.
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.
Lu 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
It just takes more taxa and more characters and all the confusion