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Thanks, Tracy, for alerting us the the
paper!
Martill et al. questionably refer the material to
Compsognathidae, on the basis of the shape of the pubic boot and its
fan-shaped neural spines of the dorsals.
The
possible postpubic air sac is an vacuity in the matrix extending from the dorsal
aspect of the pubic boot and extends half-way to the ischium. It was partially
lined with small calcite crystals. They reject the possibility this
structure might represent the mold of a urinary bladder or ovaries, as these
would be wholly anterior to the pubis or between the sacrum & the
pubis.
Unfortunately the authors do not make direct
comparisons to _Santanaraptor_ (which may not have been described when this
paper was written).
In the
same issue, a paper on the Jurassic time scale:
Palfy,
J., P.L. smith & J.K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time
scale for the Jurassic. CJES 37: 923-944.
Here
are their new stage-boundary dates. Note that the Jurassic as a whole has
been shrunk, as has the Late Jurassic relative to the Early & Middle.
Dates given are the lower time boundary for each unit:
Berriasian (J-K boundary): 141.8 +2.5
-1.8
Tithonian: 150 +3.4
-2.8
Kimmeridgian: 154.7 +3.8
-3.3
Oxfordian: 156.5 +3.1
-5.1
Callovian: 160.4 +1.1
-0.5
Bathonian: 166.0 +3.8
-5.6
Bajocian: 174.0 +1.2
-7.9
Aalenian: 178.0 +1.0
-1.5
Toarcian: 183.6 +1.7
-1.1
Pliensbachian: 191.5 +1.9
-4.7
Sinemurian: 196.5 +1.7
-5.7
Hettangian (Tr-J boundary): 199.6
+_0.4
Dates
in Ma, uncertainty in Myr.
Thomas R. Holtz,
Jr.
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