[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Cryptovolans, Scanoriopteryx and Epidendrosaurus!



Steven Coombs wrote-

> I've returned from a lenghtly absence from the dml, well I'm back now and
> I'm beginning to get back into mode, and I read up a bit on Cryptovolans,
> Scansoriopteryx and Epidendrosaurus and I would like to know what are the
> masses and lenghts of these three genera?

Scansoriopteryx's holotype is 130 mm long, and the referred specimen
(Epidendrosaurus' holotype) is approximately the same size (maybe a few mm
shorter).  The approximate mass of each specimen was 6 grams, based on
comparison of femoral length with the Eichstatt Archaeopteryx.  Of course,
they were not fully grown.

There are unfortunately very few osteological measurements of Cryptovolans,
but figure 1 indicates the holotype's tibia is 132 mm long.  The tibia is
said to be "slightly longer" proportionally than Archaeopteryx, which has a
tibiofemoral ratio of 1.29-1.48.  The referred specimen (LPM 0159) has a
tibia 105 mm long.  The tibiofemoral ratio of this specimen is said to be
10% less than Microraptor (1.28), resulting in a femur about 89 mm long.
The holotype is supposedly 1.5 times larger than LPM 0159 and has a
"slightly" larger tibiofemoral ratio.  So it's ratio is "slightly" larger
than both Archaeopteryx's (1.29-1.48) and LPM 1059's (1.18).  Maybe it was
about 1.3, giving a femoral length of ~100 mm (but note the ~2/3 size of the
referred specimen must have been extremely imprecise).  It would then be
about half the size of the fighting Velociraptor specimen, resulting in an
estimated mass of 1.9 kg.  That's ~3.3 times the estimated mass of
Wellnhoferia, which is pretty close to Paul's estimate of ~2.5 times
(especially considering how quickly mass increases with length).  The actual
length of Cryptovolans is difficult to estimate without accurate axial
measurements, though the tail is about 500 mm long.  Assuming presacral
proportions like Sinornithosaurus, the holotype may have been ~830 mm long.
This fits well with it being about half the size of the fighting
Velociraptor, considering its lower amount of caudal vertebrae.  The
referred specimen would then be ~740 mm long, and 1.3 kg.  So my very
tentative estimates for Cryptovolans' length and mass are-
Holotype- ~830 mm long, ~1.9 kg
Referred- ~740 mm long, ~1.3 kg
The specimen preserved with Omnivoropteryx has not been shown to be
Cryptovolans yet (though the manual phalangeal proportions should clear this
up).

Mickey Mortimer