Other ichthyosauriforms were the Ichthyopterygia, containing the Ichthyosauria and allies.
2.
Basal Ichthyopterygia have a parietal eye opening between the paired parietal bones.
3.
Basal Ichthyopterygia still have two sacral vertebrae but these are not fused.
4.
In 1840, Richard Owen named an order Ichthyopterygia as an alternative concept.
5.
Motani found it to be more basal than the Ichthyopterygia and named an encompassing clade Ichthyosauriformes.
6.
It has generally been considered an ichthyopterygian until Motani ( 2000 ) showed that it lacks the basal synapomorphies of Ichthyopterygia.
7.
Like the Ichthyopterygia, the Hupehsuchia have a pointed snout and show polydactyly, the possession of more than five fingers or toes.
8.
A basal ichthyosauriform is " Cartorhynchus "; more derived species are part of the Ichthyopterygia which again include the Ichthyosauria.
9.
The removal / inclusion of Ichthyopterygia was found to affect the topology the most-switching the positions of the " Eusaurosphargis " + " Helveticosaurus " and Thalattosauriformes clades, and altering the positions of several taxa within Eosauropterygia, which are not shown.
10.
These very early " proto-ichthyosaurs " had such a distinctive build compared to " ichthyosaurs proper " that Motani excluded them from the Ichthyosauria and placed them in a basal position in a larger clade, the Ichthyopterygia ( Motani 1997, Motani et al . 1998 ).
