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comments on KJ1 and KJ2



Thanks to former dinolister, Tracy Ford, a photocopy of Chris Bennett's
'New crested specimens of the Late Cretaceous pterosaur Nyctosaurus'
Paläontologische Zeitschrift 77(1) 61-75, 2003 fell into my paws.

Fascinating animals. Would love to see what the smoke trails in a
wind-tunnel would do with a model of either one. The descriptions were
fantastic. The illustrations continued, unfortunately, a pterosaur
ptradition of small-scale outlines, rather than detailed illuminations,
especially of the skulls and pelvis. Hopefully that will change someday.

Just a few questions:

1. Was wondering why the long straight structures associated with the
metacarpal IVs are identified as ossified tendons rather than vestigial
metacarpal I-IIIs.

2. Was wondering how FHSM [= SMM] 11311 fit into the clade, especially
considering the bump on the rostrum that looks like a  solidified
version of the premax crest on a germanodactylid.

3. The hypothesis of crests appearing only at some level of maturity
makes me wonder about the baby/immature Tupuxuara skull I saw in Tucson
some years back that sported a large if immaturely rounded crest -- and
Pterorhynchus, which has an unfused scapula/coracoid and a large soft
crest. Perhaps the crest/crestless forms of Nyctosaurus should be
considered separate species? IMHO the different morphologies of the
skulls and mandibles may also lead in this direction.

4. I'm interested in Chris's comment that the scapulae in nyctosaurs
were expanded medially [and were obviously rotated laterally], but did
not articulate with the notarium. How does this work?

5. Does the addition of a crest, at least for some nyctosaurs, move it
any closer, phylgenetically, to the clade that also includes Pteranodon?
The rising posterior premaxilla along the anterior rim of a tall crest
is also shared by P. sternbergi.

David Peters
St. Louis