Some Observations on Nyctosaurus

["Jaime Headden" <ja_headden@qilong.8m.com>]

Thanks to Marco Auditore for sending me this paper, and permitting me to run 
over the discussions and data. I have a few
observations to make on the nature of the skull and postcrania that Chris 
Bennett describes.

  Bennett, S. C. 2003. New crested specimens of the Late Cretaceous pterosaur 
*Nyctosaurus*. _Paläontologische Zeitschrift_
77(1):61-75.

  The first observation I have is on the taphonomy: in KJ1, nearly all the 
elements are aligned within 30 degrees of one another,
suggesting deposition in a flow, rather than still, environment; elements not 
in this 30 degree range include the proximal ends of
the first wing-digit phalanges, the disarticulated lower jaw, the left wing 
metacarpal, and "ossified tendons" associated with the
latter. The skull excluding the cranial crest is aligned cross-wise to this 
degree, and is largely parallel to the lower jaw,
suggesting that the crest may have had more of an effect in-stream during 
deposition than the bulk of the skull. In KJ2, the
elements are aligned large in two directions, with the left side of the slab 
aligned about 25 degrees from the slab midline to the
left, and the right side aligned to the right about 30 degrees, though this 
right side median is much more partial to cross-wise
elements than is the left side, including the skull; the lower jaw is aligned 
parallel to the right-side median, and the left side
median lacks nearly any cross-wise elements except for portions of the broken 
crest. This is also suggestive of a flow-like
deposition. Since I am unaware of the depositional direction of the slabs in 
situ, I cannot speculate otherwise, but the nature of
the sediment, being chalk, indicates these were offshore, and not part of an 
inshore, stream or riverine environment, so the Great
Interior Seaway most likely had a relatively strong sub-surface flow.

  My second observation is on the arm: based on the above alignment of 
elements, it is considerable to note that the  "ossified
tendons" noted by Bennett are almost _always_ associated with wing elements. In 
KJ1, these are associated with the radius, ulna, and
the wing metacarpals. Two are associated parallel and adjacent to the right 
MCIV, one is associated about 20 degrees and adjacent to
the left MCIV, and one is associated parallel and adjacent to the ulna and 
radius, which were found as float near the rest of the
specimen. In KJ2, the tendons are preserved parallel (< 20 degrees) and 
adjacent to the left MCIV, perpendicular to and almost
abutting one end of the right radius and parallel to the posterior ramus of the 
crest, and as fragments both cross-wise and diagonal
to the flow on the right side of the slab between the proximal and distal 
syncarpals, which are near to the right MCIV and first
wing phalanx. This tells me that these elements are intimately associated with 
the wing. Furthermore, the morphology of parallel
fused fibers with striated but longitudinal structure, even though one end 
(proximal?) is bifurcated in KJ1 for two elements,
suggests to me that these may very well pertain to very vestigial metacarpals 
I-III; their distal morphology is rounded and
truncated, so it may be likely phalanges could have been present, but my gut at 
least informs me otherwise, and the phalanges may
most likely be absent, and the fusion of the "tendons" as an effect of 
structural reinforcement of the elongated wing metacarpal.

  My third observation is not really an observation but a question: Bennett 
describes the other skulls of *Nyctosaurus* as
crestless, but doesn't Williston's skull (I know not the number, and figured 
only to my knowledge in Wellnhofer's pterosaur
encyclopedia and an illustration of the wall-mount of the type of *N. bonneri,* 
referred by Bennett (1991, 1994) to *N. gracilis* --
the sole postcranial material of South American *N. lamegoi* is irrelevant to 
this observation) have a midline sagittal rostral
crest, as in pterodactylids, germanodactylids, & dsungaripterids? This was not 
mentioned by Bennett. This skull is a tad different
from those of KJ1 and KJ2, though it does not appear by much, so I am curious 
about the statement Bennett used on pg. 61: "1) they
do not represent a new species[.]" What did *Nyctosaurus*' skull look like, 
then, if both are the same species, perhaps?

  See [www.oceansofkansas.com/Sternbrg/s-nyct1.jpg] for the specimen I am 
referring to.

  Cheers,

  Jaime A. Headden

  Little steps are often the hardest to take. We are too used to making leaps 
in the face of adversity, that a simple skip is so
hard to do.  We should all learn to walk soft, walk small, see the world around 
us rather than zoom by it.

  "Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)