Ryosuke Home Degu Home English version Japanese version   3-1.
Body Length  Shonisaurus popularis and probably Himalayasaurus
tibetensis (both Late Triassic), exceeding 15m, are the largest
ichthyosaurs that have been described, but there are undescribed
specimens that are larger. Among the smallest ichthyosaurs is
Chaohusaurus geishanensis (Early Triassic; the figure above),
which probably did not reach 70 cm.  3-2. Body Weight  Body mass
estimation of extinct animals is not a simple task. It usually
involves many assumptions and large margins of errors. If you
see some numbers with more than three digits of significant
figure (for example, 1234 kg), you have a good enough reason to
doubt the validity of such numbers. Scientists with conscience
would more likely give such values as 1230 kg (or 1.23E3) or
1200 kg (or 1.2E3) for the same estimate, and probably with
error margins.  I received so many questions asking how heavy
ichthyosaurs had been. I suppose school projects ask for these
values. So here are so